upgrade to 14.4.1upstream/14.4.1

125 files changed, 15720 insertions, 0 deletions

diff --git a/zmq/__init__.py b/zmq/__init__.py
new file mode 100644
index 0000000..cf4a1f7
--- /dev/null
+++ b/zmq/__init__.py
@@ -0,0 +1,63 @@
+"""Python bindings for 0MQ."""
+
+# Copyright (C) PyZMQ Developers
+# Distributed under the terms of the Modified BSD License.
+
+import os
+import sys
+import glob
+
+# load bundled libzmq, if there is one:
+
+here = os.path.dirname(__file__)
+
+bundled = []
+bundled_sodium = []
+for ext in ('pyd', 'so', 'dll', 'dylib'):
+    bundled_sodium.extend(glob.glob(os.path.join(here, 'libsodium*.%s*' % ext)))
+    bundled.extend(glob.glob(os.path.join(here, 'libzmq*.%s*' % ext)))
+
+if bundled:
+    import ctypes
+    if bundled_sodium:
+        if bundled[0].endswith('.pyd'):
+            # a Windows Extension
+            _libsodium = ctypes.cdll.LoadLibrary(bundled_sodium[0])
+        else:
+            _libsodium = ctypes.CDLL(bundled_sodium[0], mode=ctypes.RTLD_GLOBAL)
+    if bundled[0].endswith('.pyd'):
+        # a Windows Extension
+        _libzmq = ctypes.cdll.LoadLibrary(bundled[0])
+    else:
+        _libzmq = ctypes.CDLL(bundled[0], mode=ctypes.RTLD_GLOBAL)
+    del ctypes
+else:
+    import zipimport
+    try:
+        if isinstance(__loader__, zipimport.zipimporter):
+            # a zipped pyzmq egg
+            from zmq import libzmq as _libzmq
+    except (NameError, ImportError):
+        pass
+    finally:
+        del zipimport
+
+del os, sys, glob, here, bundled, bundled_sodium, ext
+
+# zmq top-level imports
+
+from zmq.backend import *
+from zmq import sugar
+from zmq.sugar import *
+from zmq import devices
+
+def get_includes():
+    """Return a list of directories to include for linking against pyzmq with cython."""
+    from os.path import join, dirname, abspath, pardir
+    base = dirname(__file__)
+    parent = abspath(join(base, pardir))
+    return [ parent ] + [ join(parent, base, subdir) for subdir in ('utils',) ]
+
+
+__all__ = ['get_includes'] + sugar.__all__ + backend.__all__
+
diff --git a/zmq/auth/__init__.py b/zmq/auth/__init__.py
new file mode 100644
index 0000000..11d3ad6
--- /dev/null
+++ b/zmq/auth/__init__.py
@@ -0,0 +1,10 @@
+"""Utilities for ZAP authentication.
+
+To run authentication in a background thread, see :mod:`zmq.auth.thread`.
+For integration with the tornado eventloop, see :mod:`zmq.auth.ioloop`.
+
+.. versionadded:: 14.1
+"""
+
+from .base import *
+from .certs import *
diff --git a/zmq/auth/base.py b/zmq/auth/base.py
new file mode 100644
index 0000000..9b4aaed
--- /dev/null
+++ b/zmq/auth/base.py
@@ -0,0 +1,272 @@
+"""Base implementation of 0MQ authentication."""
+
+# Copyright (C) PyZMQ Developers
+# Distributed under the terms of the Modified BSD License.
+
+import logging
+
+import zmq
+from zmq.utils import z85
+from zmq.utils.strtypes import bytes, unicode, b, u
+from zmq.error import _check_version
+
+from .certs import load_certificates
+
+
+CURVE_ALLOW_ANY = '*'
+VERSION = b'1.0'
+
+class Authenticator(object):
+    """Implementation of ZAP authentication for zmq connections.
+
+    Note:
+    - libzmq provides four levels of security: default NULL (which the Authenticator does
+      not see), and authenticated NULL, PLAIN, and CURVE, which the Authenticator can see.
+    - until you add policies, all incoming NULL connections are allowed
+    (classic ZeroMQ behavior), and all PLAIN and CURVE connections are denied.
+    """
+
+    def __init__(self, context=None, encoding='utf-8', log=None):
+        _check_version((4,0), "security")
+        self.context = context or zmq.Context.instance()
+        self.encoding = encoding
+        self.allow_any = False
+        self.zap_socket = None
+        self.whitelist = set()
+        self.blacklist = set()
+        # passwords is a dict keyed by domain and contains values
+        # of dicts with username:password pairs.
+        self.passwords = {}
+        # certs is dict keyed by domain and contains values
+        # of dicts keyed by the public keys from the specified location.
+        self.certs = {}
+        self.log = log or logging.getLogger('zmq.auth')
+    
+    def start(self):
+        """Create and bind the ZAP socket"""
+        self.zap_socket = self.context.socket(zmq.REP)
+        self.zap_socket.linger = 1
+        self.zap_socket.bind("inproc://zeromq.zap.01")
+
+    def stop(self):
+        """Close the ZAP socket"""
+        if self.zap_socket:
+            self.zap_socket.close()
+        self.zap_socket = None
+
+    def allow(self, *addresses):
+        """Allow (whitelist) IP address(es).
+        
+        Connections from addresses not in the whitelist will be rejected.
+        
+        - For NULL, all clients from this address will be accepted.
+        - For PLAIN and CURVE, they will be allowed to continue with authentication.
+        
+        whitelist is mutually exclusive with blacklist.
+        """
+        if self.blacklist:
+            raise ValueError("Only use a whitelist or a blacklist, not both")
+        self.whitelist.update(addresses)
+
+    def deny(self, *addresses):
+        """Deny (blacklist) IP address(es).
+        
+        Addresses not in the blacklist will be allowed to continue with authentication.
+        
+        Blacklist is mutually exclusive with whitelist.
+        """
+        if self.whitelist:
+            raise ValueError("Only use a whitelist or a blacklist, not both")
+        self.blacklist.update(addresses)
+
+    def configure_plain(self, domain='*', passwords=None):
+        """Configure PLAIN authentication for a given domain.
+        
+        PLAIN authentication uses a plain-text password file.
+        To cover all domains, use "*".
+        You can modify the password file at any time; it is reloaded automatically.
+        """
+        if passwords:
+            self.passwords[domain] = passwords
+
+    def configure_curve(self, domain='*', location=None):
+        """Configure CURVE authentication for a given domain.
+        
+        CURVE authentication uses a directory that holds all public client certificates,
+        i.e. their public keys.
+        
+        To cover all domains, use "*".
+        
+        You can add and remove certificates in that directory at any time.
+        
+        To allow all client keys without checking, specify CURVE_ALLOW_ANY for the location.
+        """
+        # If location is CURVE_ALLOW_ANY then allow all clients. Otherwise
+        # treat location as a directory that holds the certificates.
+        if location == CURVE_ALLOW_ANY:
+            self.allow_any = True
+        else:
+            self.allow_any = False
+            try:
+                self.certs[domain] = load_certificates(location)
+            except Exception as e:
+                self.log.error("Failed to load CURVE certs from %s: %s", location, e)
+
+    def handle_zap_message(self, msg):
+        """Perform ZAP authentication"""
+        if len(msg) < 6:
+            self.log.error("Invalid ZAP message, not enough frames: %r", msg)
+            if len(msg) < 2:
+                self.log.error("Not enough information to reply")
+            else:
+                self._send_zap_reply(msg[1], b"400", b"Not enough frames")
+            return
+        
+        version, request_id, domain, address, identity, mechanism = msg[:6]
+        credentials = msg[6:]
+        
+        domain = u(domain, self.encoding, 'replace')
+        address = u(address, self.encoding, 'replace')
+
+        if (version != VERSION):
+            self.log.error("Invalid ZAP version: %r", msg)
+            self._send_zap_reply(request_id, b"400", b"Invalid version")
+            return
+
+        self.log.debug("version: %r, request_id: %r, domain: %r,"
+                      " address: %r, identity: %r, mechanism: %r",
+                      version, request_id, domain,
+                      address, identity, mechanism,
+        )
+
+
+        # Is address is explicitly whitelisted or blacklisted?
+        allowed = False
+        denied = False
+        reason = b"NO ACCESS"
+
+        if self.whitelist:
+            if address in self.whitelist:
+                allowed = True
+                self.log.debug("PASSED (whitelist) address=%s", address)
+            else:
+                denied = True
+                reason = b"Address not in whitelist"
+                self.log.debug("DENIED (not in whitelist) address=%s", address)
+
+        elif self.blacklist:
+            if address in self.blacklist:
+                denied = True
+                reason = b"Address is blacklisted"
+                self.log.debug("DENIED (blacklist) address=%s", address)
+            else:
+                allowed = True
+                self.log.debug("PASSED (not in blacklist) address=%s", address)
+
+        # Perform authentication mechanism-specific checks if necessary
+        username = u("user")
+        if not denied:
+
+            if mechanism == b'NULL' and not allowed:
+                # For NULL, we allow if the address wasn't blacklisted
+                self.log.debug("ALLOWED (NULL)")
+                allowed = True
+
+            elif mechanism == b'PLAIN':
+                # For PLAIN, even a whitelisted address must authenticate
+                if len(credentials) != 2:
+                    self.log.error("Invalid PLAIN credentials: %r", credentials)
+                    self._send_zap_reply(request_id, b"400", b"Invalid credentials")
+                    return
+                username, password = [ u(c, self.encoding, 'replace') for c in credentials ]
+                allowed, reason = self._authenticate_plain(domain, username, password)
+
+            elif mechanism == b'CURVE':
+                # For CURVE, even a whitelisted address must authenticate
+                if len(credentials) != 1:
+                    self.log.error("Invalid CURVE credentials: %r", credentials)
+                    self._send_zap_reply(request_id, b"400", b"Invalid credentials")
+                    return
+                key = credentials[0]
+                allowed, reason = self._authenticate_curve(domain, key)
+
+        if allowed:
+            self._send_zap_reply(request_id, b"200", b"OK", username)
+        else:
+            self._send_zap_reply(request_id, b"400", reason)
+
+    def _authenticate_plain(self, domain, username, password):
+        """PLAIN ZAP authentication"""
+        allowed = False
+        reason = b""
+        if self.passwords:
+            # If no domain is not specified then use the default domain
+            if not domain:
+                domain = '*'
+
+            if domain in self.passwords:
+                if username in self.passwords[domain]:
+                    if password == self.passwords[domain][username]:
+                        allowed = True
+                    else:
+                        reason = b"Invalid password"
+                else:
+                    reason = b"Invalid username"
+            else:
+                reason = b"Invalid domain"
+
+            if allowed:
+                self.log.debug("ALLOWED (PLAIN) domain=%s username=%s password=%s",
+                    domain, username, password,
+                )
+            else:
+                self.log.debug("DENIED %s", reason)
+
+        else:
+            reason = b"No passwords defined"
+            self.log.debug("DENIED (PLAIN) %s", reason)
+
+        return allowed, reason
+
+    def _authenticate_curve(self, domain, client_key):
+        """CURVE ZAP authentication"""
+        allowed = False
+        reason = b""
+        if self.allow_any:
+            allowed = True
+            reason = b"OK"
+            self.log.debug("ALLOWED (CURVE allow any client)")
+        else:
+            # If no explicit domain is specified then use the default domain
+            if not domain:
+                domain = '*'
+
+            if domain in self.certs:
+                # The certs dict stores keys in z85 format, convert binary key to z85 bytes
+                z85_client_key = z85.encode(client_key)
+                if z85_client_key in self.certs[domain] or self.certs[domain] == b'OK':
+                    allowed = True
+                    reason = b"OK"
+                else:
+                    reason = b"Unknown key"
+
+                status = "ALLOWED" if allowed else "DENIED"
+                self.log.debug("%s (CURVE) domain=%s client_key=%s",
+                    status, domain, z85_client_key,
+                )
+            else:
+                reason = b"Unknown domain"
+
+        return allowed, reason
+
+    def _send_zap_reply(self, request_id, status_code, status_text, user_id='user'):
+        """Send a ZAP reply to finish the authentication."""
+        user_id = user_id if status_code == b'200' else b''
+        if isinstance(user_id, unicode):
+            user_id = user_id.encode(self.encoding, 'replace')
+        metadata = b''  # not currently used
+        self.log.debug("ZAP reply code=%s text=%s", status_code, status_text)
+        reply = [VERSION, request_id, status_code, status_text, user_id, metadata]
+        self.zap_socket.send_multipart(reply)
+
+__all__ = ['Authenticator', 'CURVE_ALLOW_ANY']
diff --git a/zmq/auth/certs.py b/zmq/auth/certs.py
new file mode 100644
index 0000000..4d26ad7
--- /dev/null
+++ b/zmq/auth/certs.py
@@ -0,0 +1,119 @@
+"""0MQ authentication related functions and classes."""
+
+# Copyright (C) PyZMQ Developers
+# Distributed under the terms of the Modified BSD License.
+
+
+import datetime
+import glob
+import io
+import os
+import zmq
+from zmq.utils.strtypes import bytes, unicode, b, u
+
+
+_cert_secret_banner = u("""#   ****  Generated on {0} by pyzmq  ****
+#   ZeroMQ CURVE **Secret** Certificate
+#   DO NOT PROVIDE THIS FILE TO OTHER USERS nor change its permissions.
+
+""")
+
+_cert_public_banner = u("""#   ****  Generated on {0} by pyzmq  ****
+#   ZeroMQ CURVE Public Certificate
+#   Exchange securely, or use a secure mechanism to verify the contents
+#   of this file after exchange. Store public certificates in your home
+#   directory, in the .curve subdirectory.
+
+""")
+
+def _write_key_file(key_filename, banner, public_key, secret_key=None, metadata=None, encoding='utf-8'):
+    """Create a certificate file"""
+    if isinstance(public_key, bytes):
+        public_key = public_key.decode(encoding)
+    if isinstance(secret_key, bytes):
+        secret_key = secret_key.decode(encoding)
+    with io.open(key_filename, 'w', encoding='utf8') as f:
+        f.write(banner.format(datetime.datetime.now()))
+
+        f.write(u('metadata\n'))
+        if metadata:
+            for k, v in metadata.items():
+                if isinstance(v, bytes):
+                    v = v.decode(encoding)
+                f.write(u("    {0} = {1}\n").format(k, v))
+
+        f.write(u('curve\n'))
+        f.write(u("    public-key = \"{0}\"\n").format(public_key))
+
+        if secret_key:
+            f.write(u("    secret-key = \"{0}\"\n").format(secret_key))
+
+
+def create_certificates(key_dir, name, metadata=None):
+    """Create zmq certificates.
+    
+    Returns the file paths to the public and secret certificate files.
+    """
+    public_key, secret_key = zmq.curve_keypair()
+    base_filename = os.path.join(key_dir, name)
+    secret_key_file = "{0}.key_secret".format(base_filename)
+    public_key_file = "{0}.key".format(base_filename)
+    now = datetime.datetime.now()
+
+    _write_key_file(public_key_file,
+                    _cert_public_banner.format(now),
+                    public_key)
+
+    _write_key_file(secret_key_file,
+                    _cert_secret_banner.format(now),
+                    public_key,
+                    secret_key=secret_key,
+                    metadata=metadata)
+
+    return public_key_file, secret_key_file
+
+
+def load_certificate(filename):
+    """Load public and secret key from a zmq certificate.
+    
+    Returns (public_key, secret_key)
+    
+    If the certificate file only contains the public key,
+    secret_key will be None.
+    """
+    public_key = None
+    secret_key = None
+    if not os.path.exists(filename):
+        raise IOError("Invalid certificate file: {0}".format(filename))
+
+    with open(filename, 'rb') as f:
+        for line in f:
+            line = line.strip()
+            if line.startswith(b'#'):
+                continue
+            if line.startswith(b'public-key'):
+                public_key = line.split(b"=", 1)[1].strip(b' \t\'"')
+            if line.startswith(b'secret-key'):
+                secret_key = line.split(b"=", 1)[1].strip(b' \t\'"')
+            if public_key and secret_key:
+                break
+    
+    return public_key, secret_key
+
+
+def load_certificates(directory='.'):
+    """Load public keys from all certificates in a directory"""
+    certs = {}
+    if not os.path.isdir(directory):
+        raise IOError("Invalid certificate directory: {0}".format(directory))
+    # Follow czmq pattern of public keys stored in *.key files.
+    glob_string = os.path.join(directory, "*.key")
+    
+    cert_files = glob.glob(glob_string)
+    for cert_file in cert_files:
+        public_key, _ = load_certificate(cert_file)
+        if public_key:
+            certs[public_key] = 'OK'
+    return certs
+
+__all__ = ['create_certificates', 'load_certificate', 'load_certificates']
diff --git a/zmq/auth/ioloop.py b/zmq/auth/ioloop.py
new file mode 100644
index 0000000..1f448b4
--- /dev/null
+++ b/zmq/auth/ioloop.py
@@ -0,0 +1,34 @@
+"""ZAP Authenticator integrated with the tornado IOLoop.
+
+.. versionadded:: 14.1
+"""
+
+# Copyright (C) PyZMQ Developers
+# Distributed under the terms of the Modified BSD License.
+
+from zmq.eventloop import ioloop, zmqstream
+from .base import Authenticator
+
+
+class IOLoopAuthenticator(Authenticator):
+    """ZAP authentication for use in the tornado IOLoop"""
+
+    def __init__(self, context=None, encoding='utf-8', log=None, io_loop=None):
+        super(IOLoopAuthenticator, self).__init__(context)
+        self.zap_stream = None
+        self.io_loop = io_loop or ioloop.IOLoop.instance()
+
+    def start(self):
+        """Start ZAP authentication"""
+        super(IOLoopAuthenticator, self).start()
+        self.zap_stream = zmqstream.ZMQStream(self.zap_socket, self.io_loop)
+        self.zap_stream.on_recv(self.handle_zap_message)
+
+    def stop(self):
+        """Stop ZAP authentication"""
+        if self.zap_stream:
+            self.zap_stream.close()
+            self.zap_stream = None
+        super(IOLoopAuthenticator, self).stop()
+
+__all__ = ['IOLoopAuthenticator']
diff --git a/zmq/auth/thread.py b/zmq/auth/thread.py
new file mode 100644
index 0000000..8c3355a
--- /dev/null
+++ b/zmq/auth/thread.py
@@ -0,0 +1,184 @@
+"""ZAP Authenticator in a Python Thread.
+
+.. versionadded:: 14.1
+"""
+
+# Copyright (C) PyZMQ Developers
+# Distributed under the terms of the Modified BSD License.
+
+import logging
+from threading import Thread
+
+import zmq
+from zmq.utils import jsonapi
+from zmq.utils.strtypes import bytes, unicode, b, u
+
+from .base import Authenticator
+
+class AuthenticationThread(Thread):
+    """A Thread for running a zmq Authenticator
+    
+    This is run in the background by ThreadedAuthenticator
+    """
+
+    def __init__(self, context, endpoint, encoding='utf-8', log=None):
+        super(AuthenticationThread, self).__init__()
+        self.context = context or zmq.Context.instance()
+        self.encoding = encoding
+        self.log = log = log or logging.getLogger('zmq.auth')
+        self.authenticator = Authenticator(context, encoding=encoding, log=log)
+
+        # create a socket to communicate back to main thread.
+        self.pipe = context.socket(zmq.PAIR)
+        self.pipe.linger = 1
+        self.pipe.connect(endpoint)
+
+    def run(self):
+        """ Start the Authentication Agent thread task """
+        self.authenticator.start()
+        zap = self.authenticator.zap_socket
+        poller = zmq.Poller()
+        poller.register(self.pipe, zmq.POLLIN)
+        poller.register(zap, zmq.POLLIN)
+        while True:
+            try:
+                socks = dict(poller.poll())
+            except zmq.ZMQError:
+                break  # interrupted
+
+            if self.pipe in socks and socks[self.pipe] == zmq.POLLIN:
+                terminate = self._handle_pipe()
+                if terminate:
+                    break
+
+            if zap in socks and socks[zap] == zmq.POLLIN:
+                self._handle_zap()
+
+        self.pipe.close()
+        self.authenticator.stop()
+
+    def _handle_zap(self):
+        """
+        Handle a message from the ZAP socket.
+        """
+        msg = self.authenticator.zap_socket.recv_multipart()
+        if not msg: return
+        self.authenticator.handle_zap_message(msg)
+
+    def _handle_pipe(self):
+        """
+        Handle a message from front-end API.
+        """
+        terminate = False
+
+        # Get the whole message off the pipe in one go
+        msg = self.pipe.recv_multipart()
+
+        if msg is None:
+            terminate = True
+            return terminate
+
+        command = msg[0]
+        self.log.debug("auth received API command %r", command)
+
+        if command == b'ALLOW':
+            addresses = [u(m, self.encoding) for m in msg[1:]]
+            try:
+                self.authenticator.allow(*addresses)
+            except Exception as e:
+                self.log.exception("Failed to allow %s", addresses)
+
+        elif command == b'DENY':
+            addresses = [u(m, self.encoding) for m in msg[1:]]
+            try:
+                self.authenticator.deny(*addresses)
+            except Exception as e:
+                self.log.exception("Failed to deny %s", addresses)
+
+        elif command == b'PLAIN':
+            domain = u(msg[1], self.encoding)
+            json_passwords = msg[2]
+            self.authenticator.configure_plain(domain, jsonapi.loads(json_passwords))
+
+        elif command == b'CURVE':
+            # For now we don't do anything with domains
+            domain = u(msg[1], self.encoding)
+
+            # If location is CURVE_ALLOW_ANY, allow all clients. Otherwise
+            # treat location as a directory that holds the certificates.
+            location = u(msg[2], self.encoding)
+            self.authenticator.configure_curve(domain, location)
+
+        elif command == b'TERMINATE':
+            terminate = True
+
+        else:
+            self.log.error("Invalid auth command from API: %r", command)
+
+        return terminate
+
+def _inherit_docstrings(cls):
+    """inherit docstrings from Authenticator, so we don't duplicate them"""
+    for name, method in cls.__dict__.items():
+        if name.startswith('_'):
+            continue
+        upstream_method = getattr(Authenticator, name, None)
+        if not method.__doc__:
+            method.__doc__ = upstream_method.__doc__
+    return cls
+
+@_inherit_docstrings
+class ThreadAuthenticator(object):
+    """Run ZAP authentication in a background thread"""
+
+    def __init__(self, context=None, encoding='utf-8', log=None):
+        self.context = context or zmq.Context.instance()
+        self.log = log
+        self.encoding = encoding
+        self.pipe = None
+        self.pipe_endpoint = "inproc://{0}.inproc".format(id(self))
+        self.thread = None
+
+    def allow(self, *addresses):
+        self.pipe.send_multipart([b'ALLOW'] + [b(a, self.encoding) for a in addresses])
+
+    def deny(self, *addresses):
+        self.pipe.send_multipart([b'DENY'] + [b(a, self.encoding) for a in addresses])
+
+    def configure_plain(self, domain='*', passwords=None):
+        self.pipe.send_multipart([b'PLAIN', b(domain, self.encoding), jsonapi.dumps(passwords or {})])
+
+    def configure_curve(self, domain='*', location=''):
+        domain = b(domain, self.encoding)
+        location = b(location, self.encoding)
+        self.pipe.send_multipart([b'CURVE', domain, location])
+
+    def start(self):
+        """Start the authentication thread"""
+        # create a socket to communicate with auth thread.
+        self.pipe = self.context.socket(zmq.PAIR)
+        self.pipe.linger = 1
+        self.pipe.bind(self.pipe_endpoint)
+        self.thread = AuthenticationThread(self.context, self.pipe_endpoint, encoding=self.encoding, log=self.log)
+        self.thread.start()
+
+    def stop(self):
+        """Stop the authentication thread"""
+        if self.pipe:
+            self.pipe.send(b'TERMINATE')
+            if self.is_alive():
+                self.thread.join()
+            self.thread = None
+            self.pipe.close()
+            self.pipe = None
+
+    def is_alive(self):
+        """Is the ZAP thread currently running?"""
+        if self.thread and self.thread.is_alive():
+            return True
+        return False
+
+    def __del__(self):
+        self.stop()
+
+__all__ = ['ThreadAuthenticator']
diff --git a/zmq/backend/__init__.py b/zmq/backend/__init__.py
new file mode 100644
index 0000000..7cac725
--- /dev/null
+++ b/zmq/backend/__init__.py
@@ -0,0 +1,45 @@
+"""Import basic exposure of libzmq C API as a backend"""
+
+# Copyright (C) PyZMQ Developers
+# Distributed under the terms of the Modified BSD License.
+
+
+import os
+import platform
+import sys
+
+from zmq.utils.sixcerpt import reraise
+
+from .select import public_api, select_backend
+
+if 'PYZMQ_BACKEND' in os.environ:
+    backend = os.environ['PYZMQ_BACKEND']
+    if backend in ('cython', 'cffi'):
+        backend = 'zmq.backend.%s' % backend
+    _ns = select_backend(backend)
+else:
+    # default to cython, fallback to cffi
+    # (reverse on PyPy)
+    if platform.python_implementation() == 'PyPy':
+        first, second = ('zmq.backend.cffi', 'zmq.backend.cython')
+    else:
+        first, second = ('zmq.backend.cython', 'zmq.backend.cffi')
+
+    try:
+        _ns = select_backend(first)
+    except Exception:
+        exc_info = sys.exc_info()
+        exc = exc_info[1]
+        try:
+            _ns = select_backend(second)
+        except ImportError:
+            # prevent 'During handling of the above exception...' on py3
+            # can't use `raise ... from` on Python 2
+            if hasattr(exc, '__cause__'):
+                exc.__cause__ = None
+            # raise the *first* error, not the fallback
+            reraise(*exc_info)
+
+globals().update(_ns)
+
+__all__ = public_api
diff --git a/zmq/backend/cffi/__init__.py b/zmq/backend/cffi/__init__.py
new file mode 100644
index 0000000..ca3164d
--- /dev/null
+++ b/zmq/backend/cffi/__init__.py
@@ -0,0 +1,22 @@
+"""CFFI backend (for PyPY)"""
+
+# Copyright (C) PyZMQ Developers
+# Distributed under the terms of the Modified BSD License.
+
+from zmq.backend.cffi import (constants, error, message, context, socket,
+                           _poll, devices, utils)
+
+__all__ = []
+for submod in (constants, error, message, context, socket,
+               _poll, devices, utils):
+    __all__.extend(submod.__all__)
+
+from .constants import *
+from .error import *
+from .message import *
+from .context import *
+from .socket import *
+from .devices import *
+from ._poll import *
+from ._cffi import zmq_version_info, ffi
+from .utils import *
diff --git a/zmq/backend/cffi/_cdefs.h b/zmq/backend/cffi/_cdefs.h
new file mode 100644
index 0000000..d330057
--- /dev/null
+++ b/zmq/backend/cffi/_cdefs.h
@@ -0,0 +1,68 @@
+void zmq_version(int *major, int *minor, int *patch);
+
+void* zmq_socket(void *context, int type);
+int zmq_close(void *socket);
+
+int zmq_bind(void *socket, const char *endpoint);
+int zmq_connect(void *socket, const char *endpoint);
+
+int zmq_errno(void);
+const char * zmq_strerror(int errnum);
+
+void* zmq_stopwatch_start(void);
+unsigned long zmq_stopwatch_stop(void *watch);
+void zmq_sleep(int seconds_);
+int zmq_device(int device, void *frontend, void *backend);
+
+int zmq_unbind(void *socket, const char *endpoint);
+int zmq_disconnect(void *socket, const char *endpoint);
+void* zmq_ctx_new();
+int zmq_ctx_destroy(void *context);
+int zmq_ctx_get(void *context, int opt);
+int zmq_ctx_set(void *context, int opt, int optval);
+int zmq_proxy(void *frontend, void *backend, void *capture);
+int zmq_socket_monitor(void *socket, const char *addr, int events);
+
+int zmq_curve_keypair (char *z85_public_key, char *z85_secret_key);
+int zmq_has (const char *capability);
+
+typedef struct { ...; } zmq_msg_t;
+typedef ... zmq_free_fn;
+
+int zmq_msg_init(zmq_msg_t *msg);
+int zmq_msg_init_size(zmq_msg_t *msg, size_t size);
+int zmq_msg_init_data(zmq_msg_t *msg,
+                      void *data,
+                      size_t size,
+                      zmq_free_fn *ffn,
+                      void *hint);
+
+size_t zmq_msg_size(zmq_msg_t *msg);
+void *zmq_msg_data(zmq_msg_t *msg);
+int zmq_msg_close(zmq_msg_t *msg);
+
+int zmq_msg_send(zmq_msg_t *msg, void *socket, int flags);
+int zmq_msg_recv(zmq_msg_t *msg, void *socket, int flags);
+
+int zmq_getsockopt(void *socket,
+                   int option_name,
+                   void *option_value,
+                   size_t *option_len);
+
+int zmq_setsockopt(void *socket,
+                   int option_name,
+                   const void *option_value,
+                   size_t option_len);
+typedef struct
+{
+    void *socket;
+    int fd;
+    short events;
+    short revents;
+} zmq_pollitem_t;
+
+int zmq_poll(zmq_pollitem_t *items, int nitems, long timeout);
+
+// miscellany
+void * memcpy(void *restrict s1, const void *restrict s2, size_t n);
+int get_ipc_path_max_len(void);
diff --git a/zmq/backend/cffi/_cffi.py b/zmq/backend/cffi/_cffi.py
new file mode 100644
index 0000000..c73ebf8
--- /dev/null
+++ b/zmq/backend/cffi/_cffi.py
@@ -0,0 +1,127 @@
+# coding: utf-8
+"""The main CFFI wrapping of libzmq"""
+
+# Copyright (C) PyZMQ Developers
+# Distributed under the terms of the Modified BSD License.
+
+
+import json
+import os
+from os.path import dirname, join
+from cffi import FFI
+
+from zmq.utils.constant_names import all_names, no_prefix
+
+
+base_zmq_version = (3,2,2)
+
+def load_compiler_config():
+    """load pyzmq compiler arguments"""
+    import zmq
+    zmq_dir = dirname(zmq.__file__)
+    zmq_parent = dirname(zmq_dir)
+    
+    fname = join(zmq_dir, 'utils', 'compiler.json')
+    if os.path.exists(fname):
+        with open(fname) as f:
+            cfg = json.load(f)
+    else:
+        cfg = {}
+    
+    cfg.setdefault("include_dirs", [])
+    cfg.setdefault("library_dirs", [])
+    cfg.setdefault("runtime_library_dirs", [])
+    cfg.setdefault("libraries", ["zmq"])
+    
+    # cast to str, because cffi can't handle unicode paths (?!)
+    cfg['libraries'] = [str(lib) for lib in cfg['libraries']]
+    for key in ("include_dirs", "library_dirs", "runtime_library_dirs"):
+        # interpret paths relative to parent of zmq (like source tree)
+        abs_paths = []
+        for p in cfg[key]:
+            if p.startswith('zmq'):
+                p = join(zmq_parent, p)
+            abs_paths.append(str(p))
+        cfg[key] = abs_paths
+    return cfg
+
+
+def zmq_version_info():
+    """Get libzmq version as tuple of ints"""
+    major = ffi.new('int*')
+    minor = ffi.new('int*')
+    patch = ffi.new('int*')
+
+    C.zmq_version(major, minor, patch)
+
+    return (int(major[0]), int(minor[0]), int(patch[0]))
+
+
+cfg = load_compiler_config()
+ffi = FFI()
+
+def _make_defines(names):
+    _names = []
+    for name in names:
+        define_line = "#define %s ..." % (name)
+        _names.append(define_line)
+
+    return "\n".join(_names)
+
+c_constant_names = []
+for name in all_names:
+    if no_prefix(name):
+        c_constant_names.append(name)
+    else:
+        c_constant_names.append("ZMQ_" + name)
+
+# load ffi definitions
+here = os.path.dirname(__file__)
+with open(os.path.join(here, '_cdefs.h')) as f:
+    _cdefs = f.read()
+
+with open(os.path.join(here, '_verify.c')) as f:
+    _verify = f.read()
+
+ffi.cdef(_cdefs)
+ffi.cdef(_make_defines(c_constant_names))
+
+try:
+    C = ffi.verify(_verify,
+        modulename='_cffi_ext',
+        libraries=cfg['libraries'],
+        include_dirs=cfg['include_dirs'],
+        library_dirs=cfg['library_dirs'],
+        runtime_library_dirs=cfg['runtime_library_dirs'],
+    )
+    _version_info = zmq_version_info()
+except Exception as e:
+    raise ImportError("PyZMQ CFFI backend couldn't find zeromq: %s\n"
+    "Please check that you have zeromq headers and libraries." % e)
+
+if _version_info < (3,2,2):
+    raise ImportError("PyZMQ CFFI backend requires zeromq >= 3.2.2,"
+        " but found %i.%i.%i" % _version_info
+    )
+
+nsp = new_sizet_pointer = lambda length: ffi.new('size_t*', length)
+
+new_uint64_pointer = lambda: (ffi.new('uint64_t*'),
+                              nsp(ffi.sizeof('uint64_t')))
+new_int64_pointer = lambda: (ffi.new('int64_t*'),
+                             nsp(ffi.sizeof('int64_t')))
+new_int_pointer = lambda: (ffi.new('int*'),
+                           nsp(ffi.sizeof('int')))
+new_binary_data = lambda length: (ffi.new('char[%d]' % (length)),
+                                  nsp(ffi.sizeof('char') * length))
+
+value_uint64_pointer = lambda val : (ffi.new('uint64_t*', val),
+                                     ffi.sizeof('uint64_t'))
+value_int64_pointer = lambda val: (ffi.new('int64_t*', val),
+                                   ffi.sizeof('int64_t'))
+value_int_pointer = lambda val: (ffi.new('int*', val),
+                                 ffi.sizeof('int'))
+value_binary_data = lambda val, length: (ffi.new('char[%d]' % (length + 1), val),
+                                         ffi.sizeof('char') * length)
+
+IPC_PATH_MAX_LEN = C.get_ipc_path_max_len()
diff --git a/zmq/backend/cffi/_poll.py b/zmq/backend/cffi/_poll.py
new file mode 100644
index 0000000..9bca34c
--- /dev/null
+++ b/zmq/backend/cffi/_poll.py
@@ -0,0 +1,56 @@
+# coding: utf-8
+"""zmq poll function"""
+
+# Copyright (C) PyZMQ Developers
+# Distributed under the terms of the Modified BSD License.
+
+from ._cffi import C, ffi, zmq_version_info
+
+from .constants import *
+
+from zmq.error import _check_rc
+
+
+def _make_zmq_pollitem(socket, flags):
+    zmq_socket = socket._zmq_socket
+    zmq_pollitem = ffi.new('zmq_pollitem_t*')
+    zmq_pollitem.socket = zmq_socket
+    zmq_pollitem.fd = 0
+    zmq_pollitem.events = flags
+    zmq_pollitem.revents = 0
+    return zmq_pollitem[0]
+
+def _make_zmq_pollitem_fromfd(socket_fd, flags):
+    zmq_pollitem = ffi.new('zmq_pollitem_t*')
+    zmq_pollitem.socket = ffi.NULL
+    zmq_pollitem.fd = socket_fd
+    zmq_pollitem.events = flags
+    zmq_pollitem.revents = 0
+    return zmq_pollitem[0]
+
+def zmq_poll(sockets, timeout):
+    cffi_pollitem_list = []
+    low_level_to_socket_obj = {}
+    for item in sockets:
+        if isinstance(item[0], int):
+            low_level_to_socket_obj[item[0]] = item
+            cffi_pollitem_list.append(_make_zmq_pollitem_fromfd(item[0], item[1]))
+        else:
+            low_level_to_socket_obj[item[0]._zmq_socket] = item
+            cffi_pollitem_list.append(_make_zmq_pollitem(item[0], item[1]))
+    items = ffi.new('zmq_pollitem_t[]', cffi_pollitem_list)
+    list_length = ffi.cast('int', len(cffi_pollitem_list))
+    c_timeout = ffi.cast('long', timeout)
+    rc = C.zmq_poll(items, list_length, c_timeout)
+    _check_rc(rc)
+    result = []
+    for index in range(len(items)):
+        if not items[index].socket == ffi.NULL:
+            if items[index].revents > 0:
+                result.append((low_level_to_socket_obj[items[index].socket][0],
+                            items[index].revents))
+        else:
+            result.append((items[index].fd, items[index].revents))
+    return result
+
+__all__ = ['zmq_poll']
diff --git a/zmq/backend/cffi/_verify.c b/zmq/backend/cffi/_verify.c
new file mode 100644
index 0000000..547840e
--- /dev/null
+++ b/zmq/backend/cffi/_verify.c
@@ -0,0 +1,12 @@
+#include <stdio.h>
+#include <sys/un.h>
+#include <string.h>
+
+#include <zmq.h>
+#include <zmq_utils.h>
+#include "zmq_compat.h"
+
+int get_ipc_path_max_len(void) {
+    struct sockaddr_un *dummy;
+    return sizeof(dummy->sun_path) - 1;
+}
diff --git a/zmq/backend/cffi/constants.py b/zmq/backend/cffi/constants.py
new file mode 100644
index 0000000..ee293e7
--- /dev/null
+++ b/zmq/backend/cffi/constants.py
@@ -0,0 +1,15 @@
+# coding: utf-8
+"""zmq constants"""
+
+from ._cffi import C, c_constant_names
+from zmq.utils.constant_names import all_names
+
+g = globals()
+for cname in c_constant_names:
+    if cname.startswith("ZMQ_"):
+        name = cname[4:]
+    else:
+        name = cname
+    g[name] = getattr(C, cname)
+
+__all__ = all_names
diff --git a/zmq/backend/cffi/context.py b/zmq/backend/cffi/context.py
new file mode 100644
index 0000000..16a7b25
--- /dev/null
+++ b/zmq/backend/cffi/context.py
@@ -0,0 +1,100 @@
+# coding: utf-8
+"""zmq Context class"""
+
+# Copyright (C) PyZMQ Developers
+# Distributed under the terms of the Modified BSD License.
+
+import weakref
+
+from ._cffi import C, ffi
+
+from .socket import *
+from .constants import *
+
+from zmq.error import ZMQError, _check_rc
+
+class Context(object):
+    _zmq_ctx = None
+    _iothreads = None
+    _closed = None
+    _sockets = None
+    _shadow = False
+
+    def __init__(self, io_threads=1, shadow=None):
+        
+        if shadow:
+            self._zmq_ctx = ffi.cast("void *", shadow)
+            self._shadow = True
+        else:
+            self._shadow = False
+            if not io_threads >= 0:
+                raise ZMQError(EINVAL)
+        
+            self._zmq_ctx = C.zmq_ctx_new()
+        if self._zmq_ctx == ffi.NULL:
+            raise ZMQError(C.zmq_errno())
+        if not shadow:
+            C.zmq_ctx_set(self._zmq_ctx, IO_THREADS, io_threads)
+        self._closed = False
+        self._sockets = set()
+    
+    @property
+    def underlying(self):
+        """The address of the underlying libzmq context"""
+        return int(ffi.cast('size_t', self._zmq_ctx))
+    
+    @property
+    def closed(self):
+        return self._closed
+
+    def _add_socket(self, socket):
+        ref = weakref.ref(socket)
+        self._sockets.add(ref)
+        return ref
+
+    def _rm_socket(self, ref):
+        if ref in self._sockets:
+            self._sockets.remove(ref)
+
+    def set(self, option, value):
+        """set a context option
+        
+        see zmq_ctx_set
+        """
+        rc = C.zmq_ctx_set(self._zmq_ctx, option, value)
+        _check_rc(rc)
+
+    def get(self, option):
+        """get context option
+        
+        see zmq_ctx_get
+        """
+        rc = C.zmq_ctx_get(self._zmq_ctx, option)
+        _check_rc(rc)
+        return rc
+
+    def term(self):
+        if self.closed:
+            return
+
+        C.zmq_ctx_destroy(self._zmq_ctx)
+
+        self._zmq_ctx = None
+        self._closed = True
+
+    def destroy(self, linger=None):
+        if self.closed:
+            return
+
+        sockets = self._sockets
+        self._sockets = set()
+        for s in sockets:
+            s = s()
+            if s and not s.closed:
+                if linger:
+                    s.setsockopt(LINGER, linger)
+                s.close()
+        
+        self.term()
+
+__all__ = ['Context']
diff --git a/zmq/backend/cffi/devices.py b/zmq/backend/cffi/devices.py
new file mode 100644
index 0000000..c7a514a
--- /dev/null
+++ b/zmq/backend/cffi/devices.py
@@ -0,0 +1,24 @@
+# coding: utf-8
+"""zmq device functions"""
+
+# Copyright (C) PyZMQ Developers
+# Distributed under the terms of the Modified BSD License.
+
+from ._cffi import C, ffi, zmq_version_info
+from .socket import Socket
+from zmq.error import ZMQError, _check_rc
+
+def device(device_type, frontend, backend):
+    rc = C.zmq_proxy(frontend._zmq_socket, backend._zmq_socket, ffi.NULL)
+    _check_rc(rc)
+
+def proxy(frontend, backend, capture=None):
+    if isinstance(capture, Socket):
+        capture = capture._zmq_socket
+    else:
+        capture = ffi.NULL
+
+    rc = C.zmq_proxy(frontend._zmq_socket, backend._zmq_socket, capture)
+    _check_rc(rc)
+
+__all__ = ['device', 'proxy']
diff --git a/zmq/backend/cffi/error.py b/zmq/backend/cffi/error.py
new file mode 100644
index 0000000..3bb64de
--- /dev/null
+++ b/zmq/backend/cffi/error.py
@@ -0,0 +1,13 @@
+"""zmq error functions"""
+
+# Copyright (C) PyZMQ Developers
+# Distributed under the terms of the Modified BSD License.
+
+from ._cffi import C, ffi
+
+def strerror(errno):
+    return ffi.string(C.zmq_strerror(errno))
+
+zmq_errno = C.zmq_errno
+
+__all__ = ['strerror', 'zmq_errno']
diff --git a/zmq/backend/cffi/message.py b/zmq/backend/cffi/message.py
new file mode 100644
index 0000000..c35decb
--- /dev/null
+++ b/zmq/backend/cffi/message.py
@@ -0,0 +1,69 @@
+"""Dummy Frame object"""
+
+# Copyright (C) PyZMQ Developers
+# Distributed under the terms of the Modified BSD License.
+
+from ._cffi import ffi, C
+
+import zmq
+from zmq.utils.strtypes import unicode
+
+try:
+    view = memoryview
+except NameError:
+    view = buffer
+
+_content = lambda x: x.tobytes() if type(x) == memoryview else x
+
+class Frame(object):
+    _data = None
+    tracker = None
+    closed = False
+    more = False
+    buffer = None
+
+
+    def __init__(self, data, track=False):
+        try:
+            view(data)
+        except TypeError:
+            raise
+
+        self._data = data
+
+        if isinstance(data, unicode):
+            raise TypeError("Unicode objects not allowed. Only: str/bytes, " +
+                            "buffer interfaces.")
+
+        self.more = False
+        self.tracker = None
+        self.closed = False
+        if track:
+            self.tracker = zmq.MessageTracker()
+
+        self.buffer = view(self.bytes)
+
+    @property
+    def bytes(self):
+        data = _content(self._data)
+        return data
+
+    def __len__(self):
+        return len(self.bytes)
+
+    def __eq__(self, other):
+        return self.bytes == _content(other)
+
+    def __str__(self):
+        if str is unicode:
+            return self.bytes.decode()
+        else:
+            return self.bytes
+
+    @property
+    def done(self):
+        return True
+
+Message = Frame
+
+__all__ = ['Frame', 'Message']
diff --git a/zmq/backend/cffi/socket.py b/zmq/backend/cffi/socket.py
new file mode 100644
index 0000000..3c42773
--- /dev/null
+++ b/zmq/backend/cffi/socket.py
@@ -0,0 +1,244 @@
+# coding: utf-8
+"""zmq Socket class"""
+
+# Copyright (C) PyZMQ Developers
+# Distributed under the terms of the Modified BSD License.
+
+import random
+import codecs
+
+import errno as errno_mod
+
+from ._cffi import (C, ffi, new_uint64_pointer, new_int64_pointer,
+                    new_int_pointer, new_binary_data, value_uint64_pointer,
+                    value_int64_pointer, value_int_pointer, value_binary_data,
+                    IPC_PATH_MAX_LEN)
+
+from .message import Frame
+from .constants import *
+
+import zmq
+from zmq.error import ZMQError, _check_rc, _check_version
+from zmq.utils.strtypes import unicode
+
+
+def new_pointer_from_opt(option, length=0):
+    from zmq.sugar.constants import (
+        int64_sockopts, bytes_sockopts,
+    )
+    if option in int64_sockopts:
+        return new_int64_pointer()
+    elif option in bytes_sockopts:
+        return new_binary_data(length)
+    else:
+        # default
+        return new_int_pointer()
+
+def value_from_opt_pointer(option, opt_pointer, length=0):
+    from zmq.sugar.constants import (
+        int64_sockopts, bytes_sockopts,
+    )
+    if option in int64_sockopts:
+        return int(opt_pointer[0])
+    elif option in bytes_sockopts:
+        return ffi.buffer(opt_pointer, length)[:]
+    else:
+        return int(opt_pointer[0])
+
+def initialize_opt_pointer(option, value, length=0):
+    from zmq.sugar.constants import (
+        int64_sockopts, bytes_sockopts,
+    )
+    if option in int64_sockopts:
+        return value_int64_pointer(value)
+    elif option in bytes_sockopts:
+        return value_binary_data(value, length)
+    else:
+        return value_int_pointer(value)
+
+
+class Socket(object):
+    context = None
+    socket_type = None
+    _zmq_socket = None
+    _closed = None
+    _ref = None
+    _shadow = False
+
+    def __init__(self, context=None, socket_type=None, shadow=None):
+        self.context = context
+        if shadow is not None:
+            self._zmq_socket = ffi.cast("void *", shadow)
+            self._shadow = True
+        else:
+            self._shadow = False
+            self._zmq_socket = C.zmq_socket(context._zmq_ctx, socket_type)
+        if self._zmq_socket == ffi.NULL:
+            raise ZMQError()
+        self._closed = False
+        if context:
+            self._ref = context._add_socket(self)
+    
+    @property
+    def underlying(self):
+        """The address of the underlying libzmq socket"""
+        return int(ffi.cast('size_t', self._zmq_socket))
+    
+    @property
+    def closed(self):
+        return self._closed
+
+    def close(self, linger=None):
+        rc = 0
+        if not self._closed and hasattr(self, '_zmq_socket'):
+            if self._zmq_socket is not None:
+                rc = C.zmq_close(self._zmq_socket)
+            self._closed = True
+            if self.context:
+                self.context._rm_socket(self._ref)
+        return rc
+
+    def bind(self, address):
+        if isinstance(address, unicode):
+            address = address.encode('utf8')
+        rc = C.zmq_bind(self._zmq_socket, address)
+        if rc < 0:
+            if IPC_PATH_MAX_LEN and C.zmq_errno() == errno_mod.ENAMETOOLONG:
+                # py3compat: address is bytes, but msg wants str
+                if str is unicode:
+                    address = address.decode('utf-8', 'replace')
+                path = address.split('://', 1)[-1]
+                msg = ('ipc path "{0}" is longer than {1} '
+                                'characters (sizeof(sockaddr_un.sun_path)).'
+                                .format(path, IPC_PATH_MAX_LEN))
+                raise ZMQError(C.zmq_errno(), msg=msg)
+            else:
+                _check_rc(rc)
+
+    def unbind(self, address):
+        _check_version((3,2), "unbind")
+        if isinstance(address, unicode):
+            address = address.encode('utf8')
+        rc = C.zmq_unbind(self._zmq_socket, address)
+        _check_rc(rc)
+
+    def connect(self, address):
+        if isinstance(address, unicode):
+            address = address.encode('utf8')
+        rc = C.zmq_connect(self._zmq_socket, address)
+        _check_rc(rc)
+
+    def disconnect(self, address):
+        _check_version((3,2), "disconnect")
+        if isinstance(address, unicode):
+            address = address.encode('utf8')
+        rc = C.zmq_disconnect(self._zmq_socket, address)
+        _check_rc(rc)
+
+    def set(self, option, value):
+        length = None
+        if isinstance(value, unicode):
+            raise TypeError("unicode not allowed, use bytes")
+        
+        if isinstance(value, bytes):
+            if option not in zmq.constants.bytes_sockopts:
+                raise TypeError("not a bytes sockopt: %s" % option)
+            length = len(value)
+        
+        c_data = initialize_opt_pointer(option, value, length)
+
+        c_value_pointer = c_data[0]
+        c_sizet = c_data[1]
+
+        rc = C.zmq_setsockopt(self._zmq_socket,
+                               option,
+                               ffi.cast('void*', c_value_pointer),
+                               c_sizet)
+        _check_rc(rc)
+
+    def get(self, option):
+        c_data = new_pointer_from_opt(option, length=255)
+
+        c_value_pointer = c_data[0]
+        c_sizet_pointer = c_data[1]
+
+        rc = C.zmq_getsockopt(self._zmq_socket,
+                               option,
+                               c_value_pointer,
+                               c_sizet_pointer)
+        _check_rc(rc)
+        
+        sz = c_sizet_pointer[0]
+        v = value_from_opt_pointer(option, c_value_pointer, sz)
+        if option != zmq.IDENTITY and option in zmq.constants.bytes_sockopts and v.endswith(b'\0'):
+            v = v[:-1]
+        return v
+
+    def send(self, message, flags=0, copy=False, track=False):
+        if isinstance(message, unicode):
+            raise TypeError("Message must be in bytes, not an unicode Object")
+
+        if isinstance(message, Frame):
+            message = message.bytes
+
+        zmq_msg = ffi.new('zmq_msg_t*')
+        c_message = ffi.new('char[]', message)
+        rc = C.zmq_msg_init_size(zmq_msg, len(message))
+        C.memcpy(C.zmq_msg_data(zmq_msg), c_message, len(message))
+
+        rc = C.zmq_msg_send(zmq_msg, self._zmq_socket, flags)
+        C.zmq_msg_close(zmq_msg)
+        _check_rc(rc)
+
+        if track:
+            return zmq.MessageTracker()
+
+    def recv(self, flags=0, copy=True, track=False):
+        zmq_msg = ffi.new('zmq_msg_t*')
+        C.zmq_msg_init(zmq_msg)
+
+        rc = C.zmq_msg_recv(zmq_msg, self._zmq_socket, flags)
+
+        if rc < 0:
+            C.zmq_msg_close(zmq_msg)
+            _check_rc(rc)
+
+        _buffer = ffi.buffer(C.zmq_msg_data(zmq_msg), C.zmq_msg_size(zmq_msg))
+        value = _buffer[:]
+        C.zmq_msg_close(zmq_msg)
+
+        frame = Frame(value, track=track)
+        frame.more = self.getsockopt(RCVMORE)
+
+        if copy:
+            return frame.bytes
+        else:
+            return frame
+    
+    def monitor(self, addr, events=-1):
+        """s.monitor(addr, flags)
+
+        Start publishing socket events on inproc.
+        See libzmq docs for zmq_monitor for details.
+        
+        Note: requires libzmq >= 3.2
+        
+        Parameters
+        ----------
+        addr : str
+            The inproc url used for monitoring. Passing None as
+            the addr will cause an existing socket monitor to be
+            deregistered.
+        events : int [default: zmq.EVENT_ALL]
+            The zmq event bitmask for which events will be sent to the monitor.
+        """
+        
+        _check_version((3,2), "monitor")
+        if events < 0:
+            events = zmq.EVENT_ALL
+        if addr is None:
+            addr = ffi.NULL
+        rc = C.zmq_socket_monitor(self._zmq_socket, addr, events)
+
+
+__all__ = ['Socket', 'IPC_PATH_MAX_LEN']
diff --git a/zmq/backend/cffi/utils.py b/zmq/backend/cffi/utils.py
new file mode 100644
index 0000000..fde7827
--- /dev/null
+++ b/zmq/backend/cffi/utils.py
@@ -0,0 +1,62 @@
+# coding: utf-8
+"""miscellaneous zmq_utils wrapping"""
+
+# Copyright (C) PyZMQ Developers
+# Distributed under the terms of the Modified BSD License.
+
+from ._cffi import ffi, C
+
+from zmq.error import ZMQError, _check_rc, _check_version
+from zmq.utils.strtypes import unicode
+
+def has(capability):
+    """Check for zmq capability by name (e.g. 'ipc', 'curve')
+    
+    .. versionadded:: libzmq-4.1
+    .. versionadded:: 14.1
+    """
+    _check_version((4,1), 'zmq.has')
+    if isinstance(capability, unicode):
+        capability = capability.encode('utf8')
+    return bool(C.zmq_has(capability))
+    
+def curve_keypair():
+    """generate a Z85 keypair for use with zmq.CURVE security
+    
+    Requires libzmq (≥ 4.0) to have been linked with libsodium.
+    
+    Returns
+    -------
+    (public, secret) : two bytestrings
+        The public and private keypair as 40 byte z85-encoded bytestrings.
+    """
+    _check_version((3,2), "monitor")
+    public = ffi.new('char[64]')
+    private = ffi.new('char[64]')
+    rc = C.zmq_curve_keypair(public, private)
+    _check_rc(rc)
+    return ffi.buffer(public)[:40], ffi.buffer(private)[:40]
+
+
+class Stopwatch(object):
+    def __init__(self):
+        self.watch = ffi.NULL
+
+    def start(self):
+        if self.watch == ffi.NULL:
+            self.watch = C.zmq_stopwatch_start()
+        else:
+            raise ZMQError('Stopwatch is already runing.')
+
+    def stop(self):
+        if self.watch == ffi.NULL:
+            raise ZMQError('Must start the Stopwatch before calling stop.')
+        else:
+            time = C.zmq_stopwatch_stop(self.watch)
+            self.watch = ffi.NULL
+            return time
+
+    def sleep(self, seconds):
+        C.zmq_sleep(seconds)
+
+__all__ = ['has', 'curve_keypair', 'Stopwatch']
diff --git a/zmq/backend/cython/__init__.py b/zmq/backend/cython/__init__.py
new file mode 100644
index 0000000..e535818
--- /dev/null
+++ b/zmq/backend/cython/__init__.py
@@ -0,0 +1,23 @@
+"""Python bindings for core 0MQ objects."""
+
+# Copyright (C) PyZMQ Developers
+# Distributed under the terms of the Lesser GNU Public License (LGPL).
+
+from . import (constants, error, message, context,
+                      socket, utils, _poll, _version, _device )
+
+__all__ = []
+for submod in (constants, error, message, context,
+               socket, utils, _poll, _version, _device):
+    __all__.extend(submod.__all__)
+
+from .constants import *
+from .error import *
+from .message import *
+from .context import *
+from .socket import *
+from ._poll import *
+from .utils import *
+from ._device import *
+from ._version import *
+
diff --git a/zmq/backend/cython/_device.pyx b/zmq/backend/cython/_device.pyx
new file mode 100644
index 0000000..eea0a00
--- /dev/null
+++ b/zmq/backend/cython/_device.pyx
@@ -0,0 +1,89 @@
+"""Python binding for 0MQ device function."""
+
+#
+#    Copyright (c) 2010-2011 Brian E. Granger & Min Ragan-Kelley
+#
+#    This file is part of pyzmq.
+#
+#    pyzmq is free software; you can redistribute it and/or modify it under
+#    the terms of the Lesser GNU General Public License as published by
+#    the Free Software Foundation; either version 3 of the License, or
+#    (at your option) any later version.
+#
+#    pyzmq is distributed in the hope that it will be useful,
+#    but WITHOUT ANY WARRANTY; without even the implied warranty of
+#    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+#    Lesser GNU General Public License for more details.
+#
+#    You should have received a copy of the Lesser GNU General Public License
+#    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+#
+
+#-----------------------------------------------------------------------------
+# Imports
+#-----------------------------------------------------------------------------
+
+from libzmq cimport zmq_device, zmq_proxy, ZMQ_VERSION_MAJOR
+from zmq.backend.cython.socket cimport Socket as cSocket
+from zmq.backend.cython.checkrc cimport _check_rc
+
+#-----------------------------------------------------------------------------
+# Basic device API
+#-----------------------------------------------------------------------------
+
+def device(int device_type, cSocket frontend, cSocket backend=None):
+    """device(device_type, frontend, backend)
+
+    Start a zeromq device.
+    
+    .. deprecated:: libzmq-3.2
+        Use zmq.proxy
+
+    Parameters
+    ----------
+    device_type : (QUEUE, FORWARDER, STREAMER)
+        The type of device to start.
+    frontend : Socket
+        The Socket instance for the incoming traffic.
+    backend : Socket
+        The Socket instance for the outbound traffic.
+    """
+    if ZMQ_VERSION_MAJOR >= 3:
+        return proxy(frontend, backend)
+
+    cdef int rc = 0
+    with nogil:
+        rc = zmq_device(device_type, frontend.handle, backend.handle)
+    _check_rc(rc)
+    return rc
+
+def proxy(cSocket frontend, cSocket backend, cSocket capture=None):
+    """proxy(frontend, backend, capture)
+    
+    Start a zeromq proxy (replacement for device).
+    
+    .. versionadded:: libzmq-3.2
+    .. versionadded:: 13.0
+    
+    Parameters
+    ----------
+    frontend : Socket
+        The Socket instance for the incoming traffic.
+    backend : Socket
+        The Socket instance for the outbound traffic.
+    capture : Socket (optional)
+        The Socket instance for capturing traffic.
+    """
+    cdef int rc = 0
+    cdef void* capture_handle
+    if isinstance(capture, cSocket):
+        capture_handle = capture.handle
+    else:
+        capture_handle = NULL
+    with nogil:
+        rc = zmq_proxy(frontend.handle, backend.handle, capture_handle)
+    _check_rc(rc)
+    return rc
+
+__all__ = ['device', 'proxy']
+
diff --git a/zmq/backend/cython/_poll.pyx b/zmq/backend/cython/_poll.pyx
new file mode 100644
index 0000000..5bed46b
--- /dev/null
+++ b/zmq/backend/cython/_poll.pyx
@@ -0,0 +1,137 @@
+"""0MQ polling related functions and classes."""
+
+#
+#    Copyright (c) 2010-2011 Brian E. Granger & Min Ragan-Kelley
+#
+#    This file is part of pyzmq.
+#
+#    pyzmq is free software; you can redistribute it and/or modify it under
+#    the terms of the Lesser GNU General Public License as published by
+#    the Free Software Foundation; either version 3 of the License, or
+#    (at your option) any later version.
+#
+#    pyzmq is distributed in the hope that it will be useful,
+#    but WITHOUT ANY WARRANTY; without even the implied warranty of
+#    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+#    Lesser GNU General Public License for more details.
+#
+#    You should have received a copy of the Lesser GNU General Public License
+#    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+#
+
+#-----------------------------------------------------------------------------
+# Imports
+#-----------------------------------------------------------------------------
+
+from libc.stdlib cimport free, malloc
+
+from libzmq cimport zmq_pollitem_t, ZMQ_VERSION_MAJOR
+from libzmq cimport zmq_poll as zmq_poll_c
+from socket cimport Socket
+
+import sys
+
+from zmq.backend.cython.checkrc cimport _check_rc
+
+#-----------------------------------------------------------------------------
+# Polling related methods
+#-----------------------------------------------------------------------------
+
+# version-independent typecheck for int/long
+if sys.version_info[0] >= 3:
+    int_t = int
+else:
+    int_t = (int,long)
+
+
+def zmq_poll(sockets, long timeout=-1):
+    """zmq_poll(sockets, timeout=-1)
+
+    Poll a set of 0MQ sockets, native file descs. or sockets.
+
+    Parameters
+    ----------
+    sockets : list of tuples of (socket, flags)
+        Each element of this list is a two-tuple containing a socket
+        and a flags. The socket may be a 0MQ socket or any object with
+        a ``fileno()`` method. The flags can be zmq.POLLIN (for detecting
+        for incoming messages), zmq.POLLOUT (for detecting that send is OK)
+        or zmq.POLLIN|zmq.POLLOUT for detecting both.
+    timeout : int
+        The number of milliseconds to poll for. Negative means no timeout.
+    """
+    cdef int rc, i
+    cdef zmq_pollitem_t *pollitems = NULL
+    cdef int nsockets = <int>len(sockets)
+    cdef Socket current_socket
+    
+    if nsockets == 0:
+        return []
+    
+    pollitems = <zmq_pollitem_t *>malloc(nsockets*sizeof(zmq_pollitem_t))
+    if pollitems == NULL:
+        raise MemoryError("Could not allocate poll items")
+        
+    if ZMQ_VERSION_MAJOR < 3:
+        # timeout is us in 2.x, ms in 3.x
+        # expected input is ms (matches 3.x)
+        timeout = 1000*timeout
+    
+    for i in range(nsockets):
+        s, events = sockets[i]
+        if isinstance(s, Socket):
+            pollitems[i].socket = (<Socket>s).handle
+            pollitems[i].events = events
+            pollitems[i].revents = 0
+        elif isinstance(s, int_t):
+            pollitems[i].socket = NULL
+            pollitems[i].fd = s
+            pollitems[i].events = events
+            pollitems[i].revents = 0
+        elif hasattr(s, 'fileno'):
+            try:
+                fileno = int(s.fileno())
+            except:
+                free(pollitems)
+                raise ValueError('fileno() must return a valid integer fd')
+            else:
+                pollitems[i].socket = NULL
+                pollitems[i].fd = fileno
+                pollitems[i].events = events
+                pollitems[i].revents = 0
+        else:
+            free(pollitems)
+            raise TypeError(
+                "Socket must be a 0MQ socket, an integer fd or have "
+                "a fileno() method: %r" % s
+            )
+    
+
+    with nogil:
+        rc = zmq_poll_c(pollitems, nsockets, timeout)
+    
+    if rc < 0:
+        free(pollitems)
+        _check_rc(rc)
+    
+    results = []
+    for i in range(nsockets):
+        revents = pollitems[i].revents
+        # for compatibility with select.poll:
+        # - only return sockets with non-zero status
+        # - return the fd for plain sockets
+        if revents > 0:
+            if pollitems[i].socket != NULL:
+                s = sockets[i][0]
+            else:
+                s = pollitems[i].fd
+            results.append((s, revents))
+
+    free(pollitems)
+    return results
+
+#-----------------------------------------------------------------------------
+# Symbols to export
+#-----------------------------------------------------------------------------
+
+__all__ = [ 'zmq_poll' ]
diff --git a/zmq/backend/cython/_version.pyx b/zmq/backend/cython/_version.pyx
new file mode 100644
index 0000000..02cf6fc
--- /dev/null
+++ b/zmq/backend/cython/_version.pyx
@@ -0,0 +1,43 @@
+"""PyZMQ and 0MQ version functions."""
+
+#
+#    Copyright (c) 2010-2011 Brian E. Granger & Min Ragan-Kelley
+#
+#    This file is part of pyzmq.
+#
+#    pyzmq is free software; you can redistribute it and/or modify it under
+#    the terms of the Lesser GNU General Public License as published by
+#    the Free Software Foundation; either version 3 of the License, or
+#    (at your option) any later version.
+#
+#    pyzmq is distributed in the hope that it will be useful,
+#    but WITHOUT ANY WARRANTY; without even the implied warranty of
+#    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+#    Lesser GNU General Public License for more details.
+#
+#    You should have received a copy of the Lesser GNU General Public License
+#    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+#
+
+#-----------------------------------------------------------------------------
+# Imports
+#-----------------------------------------------------------------------------
+
+from libzmq cimport _zmq_version
+
+#-----------------------------------------------------------------------------
+# Code
+#-----------------------------------------------------------------------------
+
+def zmq_version_info():
+    """zmq_version_info()
+
+    Return the version of ZeroMQ itself as a 3-tuple of ints.
+    """
+    cdef int major, minor, patch
+    _zmq_version(&major, &minor, &patch)
+    return (major, minor, patch)
+
+
+__all__ = ['zmq_version_info']
+
diff --git a/zmq/backend/cython/checkrc.pxd b/zmq/backend/cython/checkrc.pxd
new file mode 100644
index 0000000..3bf69fc
--- /dev/null
+++ b/zmq/backend/cython/checkrc.pxd
@@ -0,0 +1,23 @@
+from libc.errno cimport EINTR, EAGAIN
+from cpython cimport PyErr_CheckSignals
+from libzmq cimport zmq_errno, ZMQ_ETERM
+
+cdef inline int _check_rc(int rc) except -1:
+    """internal utility for checking zmq return condition
+    
+    and raising the appropriate Exception class
+    """
+    cdef int errno = zmq_errno()
+    PyErr_CheckSignals()
+    if rc < 0:
+        if errno == EAGAIN:
+            from zmq.error import Again
+            raise Again(errno)
+        elif errno == ZMQ_ETERM:
+            from zmq.error import ContextTerminated
+            raise ContextTerminated(errno)
+        else:
+            from zmq.error import ZMQError
+            raise ZMQError(errno)
+        # return -1
+    return 0
diff --git a/zmq/backend/cython/constant_enums.pxi b/zmq/backend/cython/constant_enums.pxi
new file mode 100644
index 0000000..3d0efd9
--- /dev/null
+++ b/zmq/backend/cython/constant_enums.pxi
@@ -0,0 +1,156 @@
+cdef extern from "zmq.h" nogil:
+
+    enum: ZMQ_VERSION
+    enum: ZMQ_VERSION_MAJOR
+    enum: ZMQ_VERSION_MINOR
+    enum: ZMQ_VERSION_PATCH
+    enum: ZMQ_NOBLOCK
+    enum: ZMQ_DONTWAIT
+    enum: ZMQ_POLLIN
+    enum: ZMQ_POLLOUT
+    enum: ZMQ_POLLERR
+    enum: ZMQ_SNDMORE
+    enum: ZMQ_STREAMER
+    enum: ZMQ_FORWARDER
+    enum: ZMQ_QUEUE
+    enum: ZMQ_IO_THREADS_DFLT
+    enum: ZMQ_MAX_SOCKETS_DFLT
+    enum: ZMQ_POLLITEMS_DFLT
+    enum: ZMQ_THREAD_PRIORITY_DFLT
+    enum: ZMQ_THREAD_SCHED_POLICY_DFLT
+    enum: ZMQ_PAIR
+    enum: ZMQ_PUB
+    enum: ZMQ_SUB
+    enum: ZMQ_REQ
+    enum: ZMQ_REP
+    enum: ZMQ_DEALER
+    enum: ZMQ_ROUTER
+    enum: ZMQ_XREQ
+    enum: ZMQ_XREP
+    enum: ZMQ_PULL
+    enum: ZMQ_PUSH
+    enum: ZMQ_XPUB
+    enum: ZMQ_XSUB
+    enum: ZMQ_UPSTREAM
+    enum: ZMQ_DOWNSTREAM
+    enum: ZMQ_STREAM
+    enum: ZMQ_EVENT_CONNECTED
+    enum: ZMQ_EVENT_CONNECT_DELAYED
+    enum: ZMQ_EVENT_CONNECT_RETRIED
+    enum: ZMQ_EVENT_LISTENING
+    enum: ZMQ_EVENT_BIND_FAILED
+    enum: ZMQ_EVENT_ACCEPTED
+    enum: ZMQ_EVENT_ACCEPT_FAILED
+    enum: ZMQ_EVENT_CLOSED
+    enum: ZMQ_EVENT_CLOSE_FAILED
+    enum: ZMQ_EVENT_DISCONNECTED
+    enum: ZMQ_EVENT_ALL
+    enum: ZMQ_EVENT_MONITOR_STOPPED
+    enum: ZMQ_NULL
+    enum: ZMQ_PLAIN
+    enum: ZMQ_CURVE
+    enum: ZMQ_GSSAPI
+    enum: ZMQ_EAGAIN "EAGAIN"
+    enum: ZMQ_EINVAL "EINVAL"
+    enum: ZMQ_EFAULT "EFAULT"
+    enum: ZMQ_ENOMEM "ENOMEM"
+    enum: ZMQ_ENODEV "ENODEV"
+    enum: ZMQ_EMSGSIZE "EMSGSIZE"
+    enum: ZMQ_EAFNOSUPPORT "EAFNOSUPPORT"
+    enum: ZMQ_ENETUNREACH "ENETUNREACH"
+    enum: ZMQ_ECONNABORTED "ECONNABORTED"
+    enum: ZMQ_ECONNRESET "ECONNRESET"
+    enum: ZMQ_ENOTCONN "ENOTCONN"
+    enum: ZMQ_ETIMEDOUT "ETIMEDOUT"
+    enum: ZMQ_EHOSTUNREACH "EHOSTUNREACH"
+    enum: ZMQ_ENETRESET "ENETRESET"
+    enum: ZMQ_HAUSNUMERO
+    enum: ZMQ_ENOTSUP "ENOTSUP"
+    enum: ZMQ_EPROTONOSUPPORT "EPROTONOSUPPORT"
+    enum: ZMQ_ENOBUFS "ENOBUFS"
+    enum: ZMQ_ENETDOWN "ENETDOWN"
+    enum: ZMQ_EADDRINUSE "EADDRINUSE"
+    enum: ZMQ_EADDRNOTAVAIL "EADDRNOTAVAIL"
+    enum: ZMQ_ECONNREFUSED "ECONNREFUSED"
+    enum: ZMQ_EINPROGRESS "EINPROGRESS"
+    enum: ZMQ_ENOTSOCK "ENOTSOCK"
+    enum: ZMQ_EFSM "EFSM"
+    enum: ZMQ_ENOCOMPATPROTO "ENOCOMPATPROTO"
+    enum: ZMQ_ETERM "ETERM"
+    enum: ZMQ_EMTHREAD "EMTHREAD"
+    enum: ZMQ_IO_THREADS
+    enum: ZMQ_MAX_SOCKETS
+    enum: ZMQ_SOCKET_LIMIT
+    enum: ZMQ_THREAD_PRIORITY
+    enum: ZMQ_THREAD_SCHED_POLICY
+    enum: ZMQ_IDENTITY
+    enum: ZMQ_SUBSCRIBE
+    enum: ZMQ_UNSUBSCRIBE
+    enum: ZMQ_LAST_ENDPOINT
+    enum: ZMQ_TCP_ACCEPT_FILTER
+    enum: ZMQ_PLAIN_USERNAME
+    enum: ZMQ_PLAIN_PASSWORD
+    enum: ZMQ_CURVE_PUBLICKEY
+    enum: ZMQ_CURVE_SECRETKEY
+    enum: ZMQ_CURVE_SERVERKEY
+    enum: ZMQ_ZAP_DOMAIN
+    enum: ZMQ_CONNECT_RID
+    enum: ZMQ_GSSAPI_PRINCIPAL
+    enum: ZMQ_GSSAPI_SERVICE_PRINCIPAL
+    enum: ZMQ_SOCKS_PROXY
+    enum: ZMQ_FD
+    enum: ZMQ_IDENTITY_FD
+    enum: ZMQ_RECONNECT_IVL_MAX
+    enum: ZMQ_SNDTIMEO
+    enum: ZMQ_RCVTIMEO
+    enum: ZMQ_SNDHWM
+    enum: ZMQ_RCVHWM
+    enum: ZMQ_MULTICAST_HOPS
+    enum: ZMQ_IPV4ONLY
+    enum: ZMQ_ROUTER_BEHAVIOR
+    enum: ZMQ_TCP_KEEPALIVE
+    enum: ZMQ_TCP_KEEPALIVE_CNT
+    enum: ZMQ_TCP_KEEPALIVE_IDLE
+    enum: ZMQ_TCP_KEEPALIVE_INTVL
+    enum: ZMQ_DELAY_ATTACH_ON_CONNECT
+    enum: ZMQ_XPUB_VERBOSE
+    enum: ZMQ_EVENTS
+    enum: ZMQ_TYPE
+    enum: ZMQ_LINGER
+    enum: ZMQ_RECONNECT_IVL
+    enum: ZMQ_BACKLOG
+    enum: ZMQ_ROUTER_MANDATORY
+    enum: ZMQ_FAIL_UNROUTABLE
+    enum: ZMQ_ROUTER_RAW
+    enum: ZMQ_IMMEDIATE
+    enum: ZMQ_IPV6
+    enum: ZMQ_MECHANISM
+    enum: ZMQ_PLAIN_SERVER
+    enum: ZMQ_CURVE_SERVER
+    enum: ZMQ_PROBE_ROUTER
+    enum: ZMQ_REQ_RELAXED
+    enum: ZMQ_REQ_CORRELATE
+    enum: ZMQ_CONFLATE
+    enum: ZMQ_ROUTER_HANDOVER
+    enum: ZMQ_TOS
+    enum: ZMQ_IPC_FILTER_PID
+    enum: ZMQ_IPC_FILTER_UID
+    enum: ZMQ_IPC_FILTER_GID
+    enum: ZMQ_GSSAPI_SERVER
+    enum: ZMQ_GSSAPI_PLAINTEXT
+    enum: ZMQ_HANDSHAKE_IVL
+    enum: ZMQ_XPUB_NODROP
+    enum: ZMQ_AFFINITY
+    enum: ZMQ_MAXMSGSIZE
+    enum: ZMQ_HWM
+    enum: ZMQ_SWAP
+    enum: ZMQ_MCAST_LOOP
+    enum: ZMQ_RECOVERY_IVL_MSEC
+    enum: ZMQ_RATE
+    enum: ZMQ_RECOVERY_IVL
+    enum: ZMQ_SNDBUF
+    enum: ZMQ_RCVBUF
+    enum: ZMQ_RCVMORE
+    enum: ZMQ_MORE
+    enum: ZMQ_SRCFD
+    enum: ZMQ_SHARED
diff --git a/zmq/backend/cython/constants.pxi b/zmq/backend/cython/constants.pxi
new file mode 100644
index 0000000..606e6cb
--- /dev/null
+++ b/zmq/backend/cython/constants.pxi
@@ -0,0 +1,318 @@
+#-----------------------------------------------------------------------------
+# Python module level constants
+#-----------------------------------------------------------------------------
+
+VERSION = ZMQ_VERSION
+VERSION_MAJOR = ZMQ_VERSION_MAJOR
+VERSION_MINOR = ZMQ_VERSION_MINOR
+VERSION_PATCH = ZMQ_VERSION_PATCH
+NOBLOCK = ZMQ_NOBLOCK
+DONTWAIT = ZMQ_DONTWAIT
+POLLIN = ZMQ_POLLIN
+POLLOUT = ZMQ_POLLOUT
+POLLERR = ZMQ_POLLERR
+SNDMORE = ZMQ_SNDMORE
+STREAMER = ZMQ_STREAMER
+FORWARDER = ZMQ_FORWARDER
+QUEUE = ZMQ_QUEUE
+IO_THREADS_DFLT = ZMQ_IO_THREADS_DFLT
+MAX_SOCKETS_DFLT = ZMQ_MAX_SOCKETS_DFLT
+POLLITEMS_DFLT = ZMQ_POLLITEMS_DFLT
+THREAD_PRIORITY_DFLT = ZMQ_THREAD_PRIORITY_DFLT
+THREAD_SCHED_POLICY_DFLT = ZMQ_THREAD_SCHED_POLICY_DFLT
+PAIR = ZMQ_PAIR
+PUB = ZMQ_PUB
+SUB = ZMQ_SUB
+REQ = ZMQ_REQ
+REP = ZMQ_REP
+DEALER = ZMQ_DEALER
+ROUTER = ZMQ_ROUTER
+XREQ = ZMQ_XREQ
+XREP = ZMQ_XREP
+PULL = ZMQ_PULL
+PUSH = ZMQ_PUSH
+XPUB = ZMQ_XPUB
+XSUB = ZMQ_XSUB
+UPSTREAM = ZMQ_UPSTREAM
+DOWNSTREAM = ZMQ_DOWNSTREAM
+STREAM = ZMQ_STREAM
+EVENT_CONNECTED = ZMQ_EVENT_CONNECTED
+EVENT_CONNECT_DELAYED = ZMQ_EVENT_CONNECT_DELAYED
+EVENT_CONNECT_RETRIED = ZMQ_EVENT_CONNECT_RETRIED
+EVENT_LISTENING = ZMQ_EVENT_LISTENING
+EVENT_BIND_FAILED = ZMQ_EVENT_BIND_FAILED
+EVENT_ACCEPTED = ZMQ_EVENT_ACCEPTED
+EVENT_ACCEPT_FAILED = ZMQ_EVENT_ACCEPT_FAILED
+EVENT_CLOSED = ZMQ_EVENT_CLOSED
+EVENT_CLOSE_FAILED = ZMQ_EVENT_CLOSE_FAILED
+EVENT_DISCONNECTED = ZMQ_EVENT_DISCONNECTED
+EVENT_ALL = ZMQ_EVENT_ALL
+EVENT_MONITOR_STOPPED = ZMQ_EVENT_MONITOR_STOPPED
+globals()['NULL'] = ZMQ_NULL
+PLAIN = ZMQ_PLAIN
+CURVE = ZMQ_CURVE
+GSSAPI = ZMQ_GSSAPI
+EAGAIN = ZMQ_EAGAIN
+EINVAL = ZMQ_EINVAL
+EFAULT = ZMQ_EFAULT
+ENOMEM = ZMQ_ENOMEM
+ENODEV = ZMQ_ENODEV
+EMSGSIZE = ZMQ_EMSGSIZE
+EAFNOSUPPORT = ZMQ_EAFNOSUPPORT
+ENETUNREACH = ZMQ_ENETUNREACH
+ECONNABORTED = ZMQ_ECONNABORTED
+ECONNRESET = ZMQ_ECONNRESET
+ENOTCONN = ZMQ_ENOTCONN
+ETIMEDOUT = ZMQ_ETIMEDOUT
+EHOSTUNREACH = ZMQ_EHOSTUNREACH
+ENETRESET = ZMQ_ENETRESET
+HAUSNUMERO = ZMQ_HAUSNUMERO
+ENOTSUP = ZMQ_ENOTSUP
+EPROTONOSUPPORT = ZMQ_EPROTONOSUPPORT
+ENOBUFS = ZMQ_ENOBUFS
+ENETDOWN = ZMQ_ENETDOWN
+EADDRINUSE = ZMQ_EADDRINUSE
+EADDRNOTAVAIL = ZMQ_EADDRNOTAVAIL
+ECONNREFUSED = ZMQ_ECONNREFUSED
+EINPROGRESS = ZMQ_EINPROGRESS
+ENOTSOCK = ZMQ_ENOTSOCK
+EFSM = ZMQ_EFSM
+ENOCOMPATPROTO = ZMQ_ENOCOMPATPROTO
+ETERM = ZMQ_ETERM
+EMTHREAD = ZMQ_EMTHREAD
+IO_THREADS = ZMQ_IO_THREADS
+MAX_SOCKETS = ZMQ_MAX_SOCKETS
+SOCKET_LIMIT = ZMQ_SOCKET_LIMIT
+THREAD_PRIORITY = ZMQ_THREAD_PRIORITY
+THREAD_SCHED_POLICY = ZMQ_THREAD_SCHED_POLICY
+IDENTITY = ZMQ_IDENTITY
+SUBSCRIBE = ZMQ_SUBSCRIBE
+UNSUBSCRIBE = ZMQ_UNSUBSCRIBE
+LAST_ENDPOINT = ZMQ_LAST_ENDPOINT
+TCP_ACCEPT_FILTER = ZMQ_TCP_ACCEPT_FILTER
+PLAIN_USERNAME = ZMQ_PLAIN_USERNAME
+PLAIN_PASSWORD = ZMQ_PLAIN_PASSWORD
+CURVE_PUBLICKEY = ZMQ_CURVE_PUBLICKEY
+CURVE_SECRETKEY = ZMQ_CURVE_SECRETKEY
+CURVE_SERVERKEY = ZMQ_CURVE_SERVERKEY
+ZAP_DOMAIN = ZMQ_ZAP_DOMAIN
+CONNECT_RID = ZMQ_CONNECT_RID
+GSSAPI_PRINCIPAL = ZMQ_GSSAPI_PRINCIPAL
+GSSAPI_SERVICE_PRINCIPAL = ZMQ_GSSAPI_SERVICE_PRINCIPAL
+SOCKS_PROXY = ZMQ_SOCKS_PROXY
+FD = ZMQ_FD
+IDENTITY_FD = ZMQ_IDENTITY_FD
+RECONNECT_IVL_MAX = ZMQ_RECONNECT_IVL_MAX
+SNDTIMEO = ZMQ_SNDTIMEO
+RCVTIMEO = ZMQ_RCVTIMEO
+SNDHWM = ZMQ_SNDHWM
+RCVHWM = ZMQ_RCVHWM
+MULTICAST_HOPS = ZMQ_MULTICAST_HOPS
+IPV4ONLY = ZMQ_IPV4ONLY
+ROUTER_BEHAVIOR = ZMQ_ROUTER_BEHAVIOR
+TCP_KEEPALIVE = ZMQ_TCP_KEEPALIVE
+TCP_KEEPALIVE_CNT = ZMQ_TCP_KEEPALIVE_CNT
+TCP_KEEPALIVE_IDLE = ZMQ_TCP_KEEPALIVE_IDLE
+TCP_KEEPALIVE_INTVL = ZMQ_TCP_KEEPALIVE_INTVL
+DELAY_ATTACH_ON_CONNECT = ZMQ_DELAY_ATTACH_ON_CONNECT
+XPUB_VERBOSE = ZMQ_XPUB_VERBOSE
+EVENTS = ZMQ_EVENTS
+TYPE = ZMQ_TYPE
+LINGER = ZMQ_LINGER
+RECONNECT_IVL = ZMQ_RECONNECT_IVL
+BACKLOG = ZMQ_BACKLOG
+ROUTER_MANDATORY = ZMQ_ROUTER_MANDATORY
+FAIL_UNROUTABLE = ZMQ_FAIL_UNROUTABLE
+ROUTER_RAW = ZMQ_ROUTER_RAW
+IMMEDIATE = ZMQ_IMMEDIATE
+IPV6 = ZMQ_IPV6
+MECHANISM = ZMQ_MECHANISM
+PLAIN_SERVER = ZMQ_PLAIN_SERVER
+CURVE_SERVER = ZMQ_CURVE_SERVER
+PROBE_ROUTER = ZMQ_PROBE_ROUTER
+REQ_RELAXED = ZMQ_REQ_RELAXED
+REQ_CORRELATE = ZMQ_REQ_CORRELATE
+CONFLATE = ZMQ_CONFLATE
+ROUTER_HANDOVER = ZMQ_ROUTER_HANDOVER
+TOS = ZMQ_TOS
+IPC_FILTER_PID = ZMQ_IPC_FILTER_PID
+IPC_FILTER_UID = ZMQ_IPC_FILTER_UID
+IPC_FILTER_GID = ZMQ_IPC_FILTER_GID
+GSSAPI_SERVER = ZMQ_GSSAPI_SERVER
+GSSAPI_PLAINTEXT = ZMQ_GSSAPI_PLAINTEXT
+HANDSHAKE_IVL = ZMQ_HANDSHAKE_IVL
+XPUB_NODROP = ZMQ_XPUB_NODROP
+AFFINITY = ZMQ_AFFINITY
+MAXMSGSIZE = ZMQ_MAXMSGSIZE
+HWM = ZMQ_HWM
+SWAP = ZMQ_SWAP
+MCAST_LOOP = ZMQ_MCAST_LOOP
+RECOVERY_IVL_MSEC = ZMQ_RECOVERY_IVL_MSEC
+RATE = ZMQ_RATE
+RECOVERY_IVL = ZMQ_RECOVERY_IVL
+SNDBUF = ZMQ_SNDBUF
+RCVBUF = ZMQ_RCVBUF
+RCVMORE = ZMQ_RCVMORE
+MORE = ZMQ_MORE
+SRCFD = ZMQ_SRCFD
+SHARED = ZMQ_SHARED
+
+#-----------------------------------------------------------------------------
+# Symbols to export
+#-----------------------------------------------------------------------------
+__all__ = [
+  "VERSION",
+  "VERSION_MAJOR",
+  "VERSION_MINOR",
+  "VERSION_PATCH",
+  "NOBLOCK",
+  "DONTWAIT",
+  "POLLIN",
+  "POLLOUT",
+  "POLLERR",
+  "SNDMORE",
+  "STREAMER",
+  "FORWARDER",
+  "QUEUE",
+  "IO_THREADS_DFLT",
+  "MAX_SOCKETS_DFLT",
+  "POLLITEMS_DFLT",
+  "THREAD_PRIORITY_DFLT",
+  "THREAD_SCHED_POLICY_DFLT",
+  "PAIR",
+  "PUB",
+  "SUB",
+  "REQ",
+  "REP",
+  "DEALER",
+  "ROUTER",
+  "XREQ",
+  "XREP",
+  "PULL",
+  "PUSH",
+  "XPUB",
+  "XSUB",
+  "UPSTREAM",
+  "DOWNSTREAM",
+  "STREAM",
+  "EVENT_CONNECTED",
+  "EVENT_CONNECT_DELAYED",
+  "EVENT_CONNECT_RETRIED",
+  "EVENT_LISTENING",
+  "EVENT_BIND_FAILED",
+  "EVENT_ACCEPTED",
+  "EVENT_ACCEPT_FAILED",
+  "EVENT_CLOSED",
+  "EVENT_CLOSE_FAILED",
+  "EVENT_DISCONNECTED",
+  "EVENT_ALL",
+  "EVENT_MONITOR_STOPPED",
+  "NULL",
+  "PLAIN",
+  "CURVE",
+  "GSSAPI",
+  "EAGAIN",
+  "EINVAL",
+  "EFAULT",
+  "ENOMEM",
+  "ENODEV",
+  "EMSGSIZE",
+  "EAFNOSUPPORT",
+  "ENETUNREACH",
+  "ECONNABORTED",
+  "ECONNRESET",
+  "ENOTCONN",
+  "ETIMEDOUT",
+  "EHOSTUNREACH",
+  "ENETRESET",
+  "HAUSNUMERO",
+  "ENOTSUP",
+  "EPROTONOSUPPORT",
+  "ENOBUFS",
+  "ENETDOWN",
+  "EADDRINUSE",
+  "EADDRNOTAVAIL",
+  "ECONNREFUSED",
+  "EINPROGRESS",
+  "ENOTSOCK",
+  "EFSM",
+  "ENOCOMPATPROTO",
+  "ETERM",
+  "EMTHREAD",
+  "IO_THREADS",
+  "MAX_SOCKETS",
+  "SOCKET_LIMIT",
+  "THREAD_PRIORITY",
+  "THREAD_SCHED_POLICY",
+  "IDENTITY",
+  "SUBSCRIBE",
+  "UNSUBSCRIBE",
+  "LAST_ENDPOINT",
+  "TCP_ACCEPT_FILTER",
+  "PLAIN_USERNAME",
+  "PLAIN_PASSWORD",
+  "CURVE_PUBLICKEY",
+  "CURVE_SECRETKEY",
+  "CURVE_SERVERKEY",
+  "ZAP_DOMAIN",
+  "CONNECT_RID",
+  "GSSAPI_PRINCIPAL",
+  "GSSAPI_SERVICE_PRINCIPAL",
+  "SOCKS_PROXY",
+  "FD",
+  "IDENTITY_FD",
+  "RECONNECT_IVL_MAX",
+  "SNDTIMEO",
+  "RCVTIMEO",
+  "SNDHWM",
+  "RCVHWM",
+  "MULTICAST_HOPS",
+  "IPV4ONLY",
+  "ROUTER_BEHAVIOR",
+  "TCP_KEEPALIVE",
+  "TCP_KEEPALIVE_CNT",
+  "TCP_KEEPALIVE_IDLE",
+  "TCP_KEEPALIVE_INTVL",
+  "DELAY_ATTACH_ON_CONNECT",
+  "XPUB_VERBOSE",
+  "EVENTS",
+  "TYPE",
+  "LINGER",
+  "RECONNECT_IVL",
+  "BACKLOG",
+  "ROUTER_MANDATORY",
+  "FAIL_UNROUTABLE",
+  "ROUTER_RAW",
+  "IMMEDIATE",
+  "IPV6",
+  "MECHANISM",
+  "PLAIN_SERVER",
+  "CURVE_SERVER",
+  "PROBE_ROUTER",
+  "REQ_RELAXED",
+  "REQ_CORRELATE",
+  "CONFLATE",
+  "ROUTER_HANDOVER",
+  "TOS",
+  "IPC_FILTER_PID",
+  "IPC_FILTER_UID",
+  "IPC_FILTER_GID",
+  "GSSAPI_SERVER",
+  "GSSAPI_PLAINTEXT",
+  "HANDSHAKE_IVL",
+  "XPUB_NODROP",
+  "AFFINITY",
+  "MAXMSGSIZE",
+  "HWM",
+  "SWAP",
+  "MCAST_LOOP",
+  "RECOVERY_IVL_MSEC",
+  "RATE",
+  "RECOVERY_IVL",
+  "SNDBUF",
+  "RCVBUF",
+  "RCVMORE",
+  "MORE",
+  "SRCFD",
+  "SHARED",
+]
diff --git a/zmq/backend/cython/constants.pyx b/zmq/backend/cython/constants.pyx
new file mode 100644
index 0000000..f924f03
--- /dev/null
+++ b/zmq/backend/cython/constants.pyx
@@ -0,0 +1,32 @@
+"""0MQ Constants."""
+
+#
+#    Copyright (c) 2010 Brian E. Granger & Min Ragan-Kelley
+#
+#    This file is part of pyzmq.
+#
+#    pyzmq is free software; you can redistribute it and/or modify it under
+#    the terms of the Lesser GNU General Public License as published by
+#    the Free Software Foundation; either version 3 of the License, or
+#    (at your option) any later version.
+#
+#    pyzmq is distributed in the hope that it will be useful,
+#    but WITHOUT ANY WARRANTY; without even the implied warranty of
+#    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+#    Lesser GNU General Public License for more details.
+#
+#    You should have received a copy of the Lesser GNU General Public License
+#    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+#
+
+#-----------------------------------------------------------------------------
+# Imports
+#-----------------------------------------------------------------------------
+
+from libzmq cimport *
+
+#-----------------------------------------------------------------------------
+# Python module level constants
+#-----------------------------------------------------------------------------
+
+include "constants.pxi"
diff --git a/zmq/backend/cython/context.pxd b/zmq/backend/cython/context.pxd
new file mode 100644
index 0000000..9c9267a
--- /dev/null
+++ b/zmq/backend/cython/context.pxd
@@ -0,0 +1,41 @@
+"""0MQ Context class declaration."""
+
+#
+#    Copyright (c) 2010-2011 Brian E. Granger & Min Ragan-Kelley
+#
+#    This file is part of pyzmq.
+#
+#    pyzmq is free software; you can redistribute it and/or modify it under
+#    the terms of the Lesser GNU General Public License as published by
+#    the Free Software Foundation; either version 3 of the License, or
+#    (at your option) any later version.
+#
+#    pyzmq is distributed in the hope that it will be useful,
+#    but WITHOUT ANY WARRANTY; without even the implied warranty of
+#    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+#    Lesser GNU General Public License for more details.
+#
+#    You should have received a copy of the Lesser GNU General Public License
+#    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+#
+
+#-----------------------------------------------------------------------------
+# Code
+#-----------------------------------------------------------------------------
+
+cdef class Context:
+
+    cdef object __weakref__     # enable weakref
+    cdef void *handle           # The C handle for the underlying zmq object.
+    cdef bint _shadow           # whether the Context is a shadow wrapper of another
+    cdef void **_sockets        # A C-array containg socket handles
+    cdef size_t _n_sockets      # the number of sockets
+    cdef size_t _max_sockets    # the size of the _sockets array
+    cdef int _pid               # the pid of the process which created me (for fork safety)
+    
+    cdef public bint closed   # bool property for a closed context.
+    cdef inline int _term(self)
+    # helpers for events on _sockets in Socket.__cinit__()/close()
+    cdef inline void _add_socket(self, void* handle)
+    cdef inline void _remove_socket(self, void* handle)
+
diff --git a/zmq/backend/cython/context.pyx b/zmq/backend/cython/context.pyx
new file mode 100644
index 0000000..b527e5d
--- /dev/null
+++ b/zmq/backend/cython/context.pyx
@@ -0,0 +1,243 @@
+"""0MQ Context class."""
+# coding: utf-8
+
+# Copyright (c) PyZMQ Developers.
+# Distributed under the terms of the Lesser GNU Public License (LGPL).
+
+from libc.stdlib cimport free, malloc, realloc
+
+from libzmq cimport *
+
+cdef extern from "getpid_compat.h":
+    int getpid()
+
+from zmq.error import ZMQError
+from zmq.backend.cython.checkrc cimport _check_rc
+
+
+_instance = None
+
+cdef class Context:
+    """Context(io_threads=1)
+
+    Manage the lifecycle of a 0MQ context.
+
+    Parameters
+    ----------
+    io_threads : int
+        The number of IO threads.
+    """
+    
+    # no-op for the signature
+    def __init__(self, io_threads=1, shadow=0):
+        pass
+    
+    def __cinit__(self, int io_threads=1, size_t shadow=0, **kwargs):
+        self.handle = NULL
+        self._sockets = NULL
+        if shadow:
+            self.handle = <void *>shadow
+            self._shadow = True
+        else:
+            self._shadow = False
+            if ZMQ_VERSION_MAJOR >= 3:
+                self.handle = zmq_ctx_new()
+            else:
+                self.handle = zmq_init(io_threads)
+        
+        if self.handle == NULL:
+            raise ZMQError()
+        
+        cdef int rc = 0
+        if ZMQ_VERSION_MAJOR >= 3 and not self._shadow:
+            rc = zmq_ctx_set(self.handle, ZMQ_IO_THREADS, io_threads)
+            _check_rc(rc)
+        
+        self.closed = False
+        self._n_sockets = 0
+        self._max_sockets = 32
+        
+        self._sockets = <void **>malloc(self._max_sockets*sizeof(void *))
+        if self._sockets == NULL:
+            raise MemoryError("Could not allocate _sockets array")
+        
+        self._pid = getpid()
+    
+    def __dealloc__(self):
+        """don't touch members in dealloc, just cleanup allocations"""
+        cdef int rc
+        if self._sockets != NULL:
+            free(self._sockets)
+            self._sockets = NULL
+            self._n_sockets = 0
+
+        # we can't call object methods in dealloc as it
+        # might already be partially deleted
+        if not self._shadow:
+            self._term()
+    
+    cdef inline void _add_socket(self, void* handle):
+        """Add a socket handle to be closed when Context terminates.
+        
+        This is to be called in the Socket constructor.
+        """
+        if self._n_sockets >= self._max_sockets:
+            self._max_sockets *= 2
+            self._sockets = <void **>realloc(self._sockets, self._max_sockets*sizeof(void *))
+            if self._sockets == NULL:
+                raise MemoryError("Could not reallocate _sockets array")
+        
+        self._sockets[self._n_sockets] = handle
+        self._n_sockets += 1
+
+    cdef inline void _remove_socket(self, void* handle):
+        """Remove a socket from the collected handles.
+        
+        This should be called by Socket.close, to prevent trying to
+        close a socket a second time.
+        """
+        cdef bint found = False
+        
+        for idx in range(self._n_sockets):
+            if self._sockets[idx] == handle:
+                found=True
+                break
+        
+        if found:
+            self._n_sockets -= 1
+            if self._n_sockets:
+                # move last handle to closed socket's index
+                self._sockets[idx] = self._sockets[self._n_sockets]
+    
+    
+    @property
+    def underlying(self):
+        """The address of the underlying libzmq context"""
+        return <size_t> self.handle
+    
+    # backward-compat, though nobody is using it
+    _handle = underlying
+    
+    cdef inline int _term(self):
+        cdef int rc=0
+        if self.handle != NULL and not self.closed and getpid() == self._pid:
+            with nogil:
+                rc = zmq_ctx_destroy(self.handle)
+        self.handle = NULL
+        return rc
+    
+    def term(self):
+        """ctx.term()
+
+        Close or terminate the context.
+        
+        This can be called to close the context by hand. If this is not called,
+        the context will automatically be closed when it is garbage collected.
+        """
+        cdef int rc
+        rc = self._term()
+        self.closed = True
+    
+    def set(self, int option, optval):
+        """ctx.set(option, optval)
+
+        Set a context option.
+
+        See the 0MQ API documentation for zmq_ctx_set
+        for details on specific options.
+        
+        .. versionadded:: libzmq-3.2
+        .. versionadded:: 13.0
+
+        Parameters
+        ----------
+        option : int
+            The option to set.  Available values will depend on your
+            version of libzmq.  Examples include::
+            
+                zmq.IO_THREADS, zmq.MAX_SOCKETS
+        
+        optval : int
+            The value of the option to set.
+        """
+        cdef int optval_int_c
+        cdef int rc
+        cdef char* optval_c
+
+        if self.closed:
+            raise RuntimeError("Context has been destroyed")
+        
+        if not isinstance(optval, int):
+            raise TypeError('expected int, got: %r' % optval)
+        optval_int_c = optval
+        rc = zmq_ctx_set(self.handle, option, optval_int_c)
+        _check_rc(rc)
+
+    def get(self, int option):
+        """ctx.get(option)
+
+        Get the value of a context option.
+
+        See the 0MQ API documentation for zmq_ctx_get
+        for details on specific options.
+        
+        .. versionadded:: libzmq-3.2
+        .. versionadded:: 13.0
+
+        Parameters
+        ----------
+        option : int
+            The option to get.  Available values will depend on your
+            version of libzmq.  Examples include::
+            
+                zmq.IO_THREADS, zmq.MAX_SOCKETS
+            
+        Returns
+        -------
+        optval : int
+            The value of the option as an integer.
+        """
+        cdef int optval_int_c
+        cdef size_t sz
+        cdef int rc
+
+        if self.closed:
+            raise RuntimeError("Context has been destroyed")
+
+        rc = zmq_ctx_get(self.handle, option)
+        _check_rc(rc)
+
+        return rc
+
+    def destroy(self, linger=None):
+        """ctx.destroy(linger=None)
+        
+        Close all sockets associated with this context, and then terminate
+        the context. If linger is specified,
+        the LINGER sockopt of the sockets will be set prior to closing.
+        
+        .. warning::
+        
+            destroy involves calling ``zmq_close()``, which is **NOT** threadsafe.
+            If there are active sockets in other threads, this must not be called.
+        """
+        
+        cdef int linger_c
+        cdef bint setlinger=False
+        
+        if linger is not None:
+            linger_c = linger
+            setlinger=True
+
+        if self.handle != NULL and not self.closed and self._n_sockets:
+            while self._n_sockets:
+                if setlinger:
+                    zmq_setsockopt(self._sockets[0], ZMQ_LINGER, &linger_c, sizeof(int))
+                rc = zmq_close(self._sockets[0])
+                if rc < 0 and zmq_errno() != ZMQ_ENOTSOCK:
+                    raise ZMQError()
+                self._n_sockets -= 1
+                self._sockets[0] = self._sockets[self._n_sockets]
+        self.term()
+    
+__all__ = ['Context']
diff --git a/zmq/backend/cython/error.pyx b/zmq/backend/cython/error.pyx
new file mode 100644
index 0000000..85e785f
--- /dev/null
+++ b/zmq/backend/cython/error.pyx
@@ -0,0 +1,56 @@
+"""0MQ Error classes and functions."""
+
+#
+#    Copyright (c) 2010-2011 Brian E. Granger & Min Ragan-Kelley
+#
+#    This file is part of pyzmq.
+#
+#    pyzmq is free software; you can redistribute it and/or modify it under
+#    the terms of the Lesser GNU General Public License as published by
+#    the Free Software Foundation; either version 3 of the License, or
+#    (at your option) any later version.
+#
+#    pyzmq is distributed in the hope that it will be useful,
+#    but WITHOUT ANY WARRANTY; without even the implied warranty of
+#    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+#    Lesser GNU General Public License for more details.
+#
+#    You should have received a copy of the Lesser GNU General Public License
+#    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+#
+
+#-----------------------------------------------------------------------------
+# Imports
+#-----------------------------------------------------------------------------
+
+# allow const char*
+cdef extern from *:
+    ctypedef char* const_char_ptr "const char*"
+
+from libzmq cimport zmq_strerror, zmq_errno as zmq_errno_c
+
+from zmq.utils.strtypes import bytes
+
+def strerror(int errno):
+    """strerror(errno)
+
+    Return the error string given the error number.
+    """
+    cdef const_char_ptr str_e
+    # char * will be a bytes object:
+    str_e = zmq_strerror(errno)
+    if str is bytes:
+        # Python 2: str is bytes, so we already have the right type
+        return str_e
+    else:
+        # Python 3: decode bytes to unicode str
+        return str_e.decode()
+
+def zmq_errno():
+    """zmq_errno()
+    
+    Return the integer errno of the most recent zmq error.
+    """
+    return zmq_errno_c()
+
+__all__ = ['strerror', 'zmq_errno']
diff --git a/zmq/backend/cython/libzmq.pxd b/zmq/backend/cython/libzmq.pxd
new file mode 100644
index 0000000..e42f6d6
--- /dev/null
+++ b/zmq/backend/cython/libzmq.pxd
@@ -0,0 +1,110 @@
+"""All the C imports for 0MQ"""
+
+#
+#    Copyright (c) 2010 Brian E. Granger & Min Ragan-Kelley
+#
+#    This file is part of pyzmq.
+#
+#    pyzmq is free software; you can redistribute it and/or modify it under
+#    the terms of the Lesser GNU General Public License as published by
+#    the Free Software Foundation; either version 3 of the License, or
+#    (at your option) any later version.
+#
+#    pyzmq is distributed in the hope that it will be useful,
+#    but WITHOUT ANY WARRANTY; without even the implied warranty of
+#    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+#    Lesser GNU General Public License for more details.
+#
+#    You should have received a copy of the Lesser GNU General Public License
+#    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+#
+
+#-----------------------------------------------------------------------------
+# Imports
+#-----------------------------------------------------------------------------
+
+#-----------------------------------------------------------------------------
+# Import the C header files
+#-----------------------------------------------------------------------------
+
+cdef extern from *:
+    ctypedef void* const_void_ptr "const void *"
+    ctypedef char* const_char_ptr "const char *"
+
+cdef extern from "zmq_compat.h":
+    ctypedef signed long long int64_t "pyzmq_int64_t"
+
+include "constant_enums.pxi"
+
+cdef extern from "zmq.h" nogil:
+
+    void _zmq_version "zmq_version"(int *major, int *minor, int *patch)
+    
+    ctypedef int fd_t "ZMQ_FD_T"
+    
+    enum: errno
+    char *zmq_strerror (int errnum)
+    int zmq_errno()
+
+    void *zmq_ctx_new ()
+    int zmq_ctx_destroy (void *context)
+    int zmq_ctx_set (void *context, int option, int optval)
+    int zmq_ctx_get (void *context, int option)
+    void *zmq_init (int io_threads)
+    int zmq_term (void *context)
+    
+    # blackbox def for zmq_msg_t
+    ctypedef void * zmq_msg_t "zmq_msg_t"
+    
+    ctypedef void zmq_free_fn(void *data, void *hint)
+    
+    int zmq_msg_init (zmq_msg_t *msg)
+    int zmq_msg_init_size (zmq_msg_t *msg, size_t size)
+    int zmq_msg_init_data (zmq_msg_t *msg, void *data,
+        size_t size, zmq_free_fn *ffn, void *hint)
+    int zmq_msg_send (zmq_msg_t *msg, void *s, int flags)
+    int zmq_msg_recv (zmq_msg_t *msg, void *s, int flags)
+    int zmq_msg_close (zmq_msg_t *msg)
+    int zmq_msg_move (zmq_msg_t *dest, zmq_msg_t *src)
+    int zmq_msg_copy (zmq_msg_t *dest, zmq_msg_t *src)
+    void *zmq_msg_data (zmq_msg_t *msg)
+    size_t zmq_msg_size (zmq_msg_t *msg)
+    int zmq_msg_more (zmq_msg_t *msg)
+    int zmq_msg_get (zmq_msg_t *msg, int option)
+    int zmq_msg_set (zmq_msg_t *msg, int option, int optval)
+    const_char_ptr zmq_msg_gets (zmq_msg_t *msg, const_char_ptr property)
+    int zmq_has (const_char_ptr capability)
+
+    void *zmq_socket (void *context, int type)
+    int zmq_close (void *s)
+    int zmq_setsockopt (void *s, int option, void *optval, size_t optvallen)
+    int zmq_getsockopt (void *s, int option, void *optval, size_t *optvallen)
+    int zmq_bind (void *s, char *addr)
+    int zmq_connect (void *s, char *addr)
+    int zmq_unbind (void *s, char *addr)
+    int zmq_disconnect (void *s, char *addr)
+
+    int zmq_socket_monitor (void *s, char *addr, int flags)
+    
+    # send/recv
+    int zmq_sendbuf (void *s, const_void_ptr buf, size_t n, int flags)
+    int zmq_recvbuf (void *s, void *buf, size_t n, int flags)
+
+    ctypedef struct zmq_pollitem_t:
+        void *socket
+        int fd
+        short events
+        short revents
+
+    int zmq_poll (zmq_pollitem_t *items, int nitems, long timeout)
+
+    int zmq_device (int device_, void *insocket_, void *outsocket_)
+    int zmq_proxy (void *frontend, void *backend, void *capture)
+
+cdef extern from "zmq_utils.h" nogil:
+
+    void *zmq_stopwatch_start ()
+    unsigned long zmq_stopwatch_stop (void *watch_)
+    void zmq_sleep (int seconds_)
+    int zmq_curve_keypair (char *z85_public_key, char *z85_secret_key)
+
diff --git a/zmq/backend/cython/message.pxd b/zmq/backend/cython/message.pxd
new file mode 100644
index 0000000..4781195
--- /dev/null
+++ b/zmq/backend/cython/message.pxd
@@ -0,0 +1,63 @@
+"""0MQ Message related class declarations."""
+
+#
+#    Copyright (c) 2010-2011 Brian E. Granger & Min Ragan-Kelley
+#
+#    This file is part of pyzmq.
+#
+#    pyzmq is free software; you can redistribute it and/or modify it under
+#    the terms of the Lesser GNU General Public License as published by
+#    the Free Software Foundation; either version 3 of the License, or
+#    (at your option) any later version.
+#
+#    pyzmq is distributed in the hope that it will be useful,
+#    but WITHOUT ANY WARRANTY; without even the implied warranty of
+#    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+#    Lesser GNU General Public License for more details.
+#
+#    You should have received a copy of the Lesser GNU General Public License
+#    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+#
+
+#-----------------------------------------------------------------------------
+# Imports
+#-----------------------------------------------------------------------------
+
+from cpython cimport PyBytes_FromStringAndSize
+
+from libzmq cimport zmq_msg_t, zmq_msg_data, zmq_msg_size
+
+#-----------------------------------------------------------------------------
+# Code
+#-----------------------------------------------------------------------------
+
+cdef class MessageTracker(object):
+
+    cdef set events  # Message Event objects to track.
+    cdef set peers   # Other Message or MessageTracker objects.
+
+
+cdef class Frame:
+
+    cdef zmq_msg_t zmq_msg
+    cdef object _data      # The actual message data as a Python object.
+    cdef object _buffer    # A Python Buffer/View of the message contents
+    cdef object _bytes     # A bytes/str copy of the message.
+    cdef bint _failed_init # Flag to handle failed zmq_msg_init
+    cdef public object tracker_event  # Event for use with zmq_free_fn.
+    cdef public object tracker        # MessageTracker object.
+    cdef public bint more             # whether RCVMORE was set
+
+    cdef Frame fast_copy(self) # Create shallow copy of Message object.
+    cdef object _getbuffer(self) # Construct self._buffer.
+
+
+cdef inline object copy_zmq_msg_bytes(zmq_msg_t *zmq_msg):
+    """ Copy the data from a zmq_msg_t """
+    cdef char *data_c = NULL
+    cdef Py_ssize_t data_len_c
+    data_c = <char *>zmq_msg_data(zmq_msg)
+    data_len_c = zmq_msg_size(zmq_msg)
+    return PyBytes_FromStringAndSize(data_c, data_len_c)
+
+
diff --git a/zmq/backend/cython/message.pyx b/zmq/backend/cython/message.pyx
new file mode 100644
index 0000000..312ae12
--- /dev/null
+++ b/zmq/backend/cython/message.pyx
@@ -0,0 +1,381 @@
+"""0MQ Message related classes."""
+
+#
+#    Copyright (c) 2013 Brian E. Granger & Min Ragan-Kelley
+#
+#    This file is part of pyzmq.
+#
+#    pyzmq is free software; you can redistribute it and/or modify it under
+#    the terms of the Lesser GNU General Public License as published by
+#    the Free Software Foundation; either version 3 of the License, or
+#    (at your option) any later version.
+#
+#    pyzmq is distributed in the hope that it will be useful,
+#    but WITHOUT ANY WARRANTY; without even the implied warranty of
+#    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+#    Lesser GNU General Public License for more details.
+#
+#    You should have received a copy of the Lesser GNU General Public License
+#    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+#
+
+#-----------------------------------------------------------------------------
+# Imports
+#-----------------------------------------------------------------------------
+
+# get version-independent aliases:
+cdef extern from "pyversion_compat.h":
+    pass
+
+from cpython cimport Py_DECREF, Py_INCREF
+
+from buffers cimport asbuffer_r, viewfromobject_r
+
+cdef extern from "Python.h":
+    ctypedef int Py_ssize_t
+
+from libzmq cimport *
+
+from libc.stdio cimport fprintf, stderr as cstderr
+from libc.stdlib cimport malloc, free
+from libc.string cimport memcpy
+
+import time
+
+try:
+    # below 3.3
+    from threading import _Event as Event
+except (ImportError, AttributeError):
+    # python throws ImportError, cython throws AttributeError
+    from threading import Event
+
+import zmq
+from zmq.error import _check_version
+from zmq.backend.cython.checkrc cimport _check_rc
+from zmq.utils.strtypes import bytes,unicode,basestring
+
+#-----------------------------------------------------------------------------
+# Code
+#-----------------------------------------------------------------------------
+
+ctypedef struct zhint:
+    void *ctx
+    size_t id
+
+cdef void free_python_msg(void *data, void *vhint) nogil:
+    """A pure-C function for DECREF'ing Python-owned message data.
+    
+    Sends a message on a PUSH socket
+    
+    The hint is a `zhint` struct with two values:
+    
+    ctx (void *): pointer to the Garbage Collector's context
+    id (size_t): the id to be used to construct a zmq_msg_t that should be sent on a PUSH socket,
+       signaling the Garbage Collector to remove its reference to the object.
+    
+    - A PUSH socket is created in the context,
+    - it is connected to the garbage collector inproc channel,
+    - it sends the gc message
+    - the PUSH socket is closed
+    
+    When the Garbage Collector's PULL socket receives the message,
+    it deletes its reference to the object,
+    allowing Python to free the memory.
+    """
+    cdef void *push
+    cdef zmq_msg_t msg
+    cdef zhint *hint = <zhint *> vhint
+    if hint != NULL:
+        zmq_msg_init_size(&msg, sizeof(size_t))
+        memcpy(zmq_msg_data(&msg), &hint.id, sizeof(size_t))
+        
+        push = zmq_socket(hint.ctx, ZMQ_PUSH)
+        if push == NULL:
+            # this will happen if the context has been terminated
+            return
+        rc = zmq_connect(push, "inproc://pyzmq.gc.01")
+        if rc < 0:
+            fprintf(cstderr, "pyzmq-gc connect failed: %s\n", zmq_strerror(zmq_errno()))
+            return
+        
+        rc = zmq_msg_send(&msg, push, 0)
+        if rc < 0:
+            fprintf(cstderr, "pyzmq-gc send failed: %s\n", zmq_strerror(zmq_errno()))
+        
+        zmq_msg_close(&msg)
+        zmq_close(push)
+        free(hint)
+
+gc = None
+
+cdef class Frame:
+    """Frame(data=None, track=False)
+
+    A zmq message Frame class for non-copy send/recvs.
+
+    This class is only needed if you want to do non-copying send and recvs.
+    When you pass a string to this class, like ``Frame(s)``, the 
+    ref-count of `s` is increased by two: once because the Frame saves `s` as 
+    an instance attribute and another because a ZMQ message is created that
+    points to the buffer of `s`. This second ref-count increase makes sure
+    that `s` lives until all messages that use it have been sent. Once 0MQ
+    sends all the messages and it doesn't need the buffer of s, 0MQ will call
+    ``Py_DECREF(s)``.
+
+    Parameters
+    ----------
+
+    data : object, optional
+        any object that provides the buffer interface will be used to
+        construct the 0MQ message data.
+    track : bool [default: False]
+        whether a MessageTracker_ should be created to track this object.
+        Tracking a message has a cost at creation, because it creates a threadsafe
+        Event object.
+    
+    """
+
+    def __cinit__(self, object data=None, track=False, **kwargs):
+        cdef int rc
+        cdef char *data_c = NULL
+        cdef Py_ssize_t data_len_c=0
+        cdef zhint *hint
+
+        # init more as False
+        self.more = False
+
+        # Save the data object in case the user wants the the data as a str.
+        self._data = data
+        self._failed_init = True  # bool switch for dealloc
+        self._buffer = None       # buffer view of data
+        self._bytes = None        # bytes copy of data
+
+        # Event and MessageTracker for monitoring when zmq is done with data:
+        if track:
+            evt = Event()
+            self.tracker_event = evt
+            self.tracker = zmq.MessageTracker(evt)
+        else:
+            self.tracker_event = None
+            self.tracker = None
+
+        if isinstance(data, unicode):
+            raise TypeError("Unicode objects not allowed. Only: str/bytes, buffer interfaces.")
+
+        if data is None:
+            rc = zmq_msg_init(&self.zmq_msg)
+            _check_rc(rc)
+            self._failed_init = False
+            return
+        else:
+            asbuffer_r(data, <void **>&data_c, &data_len_c)
+        
+        # create the hint for zmq_free_fn
+        # two pointers: the gc context and a message to be sent to the gc PULL socket
+        # allows libzmq to signal to Python when it is done with Python-owned memory.
+        global gc
+        if gc is None:
+            from zmq.utils.garbage import gc
+        
+        hint = <zhint *> malloc(sizeof(zhint))
+        hint.id = gc.store(data, self.tracker_event)
+        hint.ctx = <void *> <size_t> gc._context.underlying
+        
+        rc = zmq_msg_init_data(
+                &self.zmq_msg, <void *>data_c, data_len_c, 
+                <zmq_free_fn *>free_python_msg, <void *>hint
+            )
+        if rc != 0:
+            free(hint)
+            _check_rc(rc)
+        self._failed_init = False
+    
+    def __init__(self, object data=None, track=False):
+        """Enforce signature"""
+        pass
+
+    def __dealloc__(self):
+        cdef int rc
+        if self._failed_init:
+            return
+        # This simply decreases the 0MQ ref-count of zmq_msg.
+        with nogil:
+            rc = zmq_msg_close(&self.zmq_msg)
+        _check_rc(rc)
+    
+    # buffer interface code adapted from petsc4py by Lisandro Dalcin, a BSD project
+    
+    def __getbuffer__(self, Py_buffer* buffer, int flags):
+        # new-style (memoryview) buffer interface
+        buffer.buf = zmq_msg_data(&self.zmq_msg)
+        buffer.len = zmq_msg_size(&self.zmq_msg)
+        
+        buffer.obj = self
+        buffer.readonly = 1
+        buffer.format = "B"
+        buffer.ndim = 0
+        buffer.shape = NULL
+        buffer.strides = NULL
+        buffer.suboffsets = NULL
+        buffer.itemsize = 1
+        buffer.internal = NULL
+    
+    def __getsegcount__(self, Py_ssize_t *lenp):
+        # required for getreadbuffer
+        if lenp != NULL:
+            lenp[0] = zmq_msg_size(&self.zmq_msg)
+        return 1
+    
+    def __getreadbuffer__(self, Py_ssize_t idx, void **p):
+        # old-style (buffer) interface
+        cdef char *data_c = NULL
+        cdef Py_ssize_t data_len_c
+        if idx != 0:
+            raise SystemError("accessing non-existent buffer segment")
+        # read-only, because we don't want to allow
+        # editing of the message in-place
+        data_c = <char *>zmq_msg_data(&self.zmq_msg)
+        data_len_c = zmq_msg_size(&self.zmq_msg)
+        if p != NULL:
+            p[0] = <void*>data_c
+        return data_len_c
+    
+    # end buffer interface
+    
+    def __copy__(self):
+        """Create a shallow copy of the message.
+
+        This does not copy the contents of the Frame, just the pointer.
+        This will increment the 0MQ ref count of the message, but not
+        the ref count of the Python object. That is only done once when
+        the Python is first turned into a 0MQ message.
+        """
+        return self.fast_copy()
+
+    cdef Frame fast_copy(self):
+        """Fast, cdef'd version of shallow copy of the Frame."""
+        cdef Frame new_msg
+        new_msg = Frame()
+        # This does not copy the contents, but just increases the ref-count 
+        # of the zmq_msg by one.
+        zmq_msg_copy(&new_msg.zmq_msg, &self.zmq_msg)
+        # Copy the ref to data so the copy won't create a copy when str is
+        # called.
+        if self._data is not None:
+            new_msg._data = self._data
+        if self._buffer is not None:
+            new_msg._buffer = self._buffer
+        if self._bytes is not None:
+            new_msg._bytes = self._bytes
+
+        # Frame copies share the tracker and tracker_event
+        new_msg.tracker_event = self.tracker_event
+        new_msg.tracker = self.tracker
+
+        return new_msg
+
+    def __len__(self):
+        """Return the length of the message in bytes."""
+        cdef size_t sz
+        sz = zmq_msg_size(&self.zmq_msg)
+        return sz
+        # return <int>zmq_msg_size(&self.zmq_msg)
+
+    def __str__(self):
+        """Return the str form of the message."""
+        if isinstance(self._data, bytes):
+            b = self._data
+        else:
+            b = self.bytes
+        if str is unicode:
+            return b.decode()
+        else:
+            return b
+
+    cdef inline object _getbuffer(self):
+        """Create a Python buffer/view of the message data.
+
+        This will be called only once, the first time the `buffer` property
+        is accessed. Subsequent calls use a cached copy.
+        """
+        if self._data is None:
+            return viewfromobject_r(self)
+        else:
+            return viewfromobject_r(self._data)
+    
+    @property
+    def buffer(self):
+        """A read-only buffer view of the message contents."""
+        if self._buffer is None:
+            self._buffer = self._getbuffer()
+        return self._buffer
+
+    @property
+    def bytes(self):
+        """The message content as a Python bytes object.
+
+        The first time this property is accessed, a copy of the message 
+        contents is made. From then on that same copy of the message is
+        returned.
+        """
+        if self._bytes is None:
+            self._bytes = copy_zmq_msg_bytes(&self.zmq_msg)
+        return self._bytes
+    
+    def set(self, int option, int value):
+        """Frame.set(option, value)
+        
+        Set a Frame option.
+        
+        See the 0MQ API documentation for zmq_msg_set
+        for details on specific options.
+        
+        .. versionadded:: libzmq-3.2
+        .. versionadded:: 13.0
+        """
+        cdef int rc = zmq_msg_set(&self.zmq_msg, option, value)
+        _check_rc(rc)
+
+    def get(self, option):
+        """Frame.get(option)
+
+        Get a Frame option or property.
+
+        See the 0MQ API documentation for zmq_msg_get and zmq_msg_gets
+        for details on specific options.
+
+        .. versionadded:: libzmq-3.2
+        .. versionadded:: 13.0
+        
+        .. versionchanged:: 14.3
+            add support for zmq_msg_gets (requires libzmq-4.1)
+        """
+        cdef int rc = 0
+        cdef char *property_c = NULL
+        cdef Py_ssize_t property_len_c = 0
+
+        # zmq_msg_get
+        if isinstance(option, int):
+            rc = zmq_msg_get(&self.zmq_msg, option)
+            _check_rc(rc)
+            return rc
+
+        # zmq_msg_gets
+        _check_version((4,1), "get string properties")
+        if isinstance(option, unicode):
+            option = option.encode('utf8')
+        
+        if not isinstance(option, bytes):
+            raise TypeError("expected str, got: %r" % option)
+        
+        property_c = option
+        
+        cdef const char *result = <char *>zmq_msg_gets(&self.zmq_msg, property_c)
+        if result == NULL:
+            _check_rc(-1)
+        return result.decode('utf8')
+
+# legacy Message name
+Message = Frame
+
+__all__ = ['Frame', 'Message']
diff --git a/zmq/backend/cython/rebuffer.pyx b/zmq/backend/cython/rebuffer.pyx
new file mode 100644
index 0000000..402e3b6
--- /dev/null
+++ b/zmq/backend/cython/rebuffer.pyx
@@ -0,0 +1,104 @@
+"""
+Utility for changing itemsize of memoryviews, and getting
+numpy arrays from byte-arrays that should be interpreted with a different
+itemsize.
+
+Authors
+-------
+* MinRK
+"""
+
+#-----------------------------------------------------------------------------
+#  Copyright (c) 2010-2012 Brian Granger, Min Ragan-Kelley
+#
+#  This file is part of pyzmq
+#
+#  Distributed under the terms of the New BSD License.  The full license is in
+#  the file COPYING.BSD, distributed as part of this software.
+#-----------------------------------------------------------------------------
+
+from libc.stdlib cimport malloc
+from buffers cimport *
+
+cdef inline object _rebuffer(object obj, char * format, int itemsize):
+    """clobber the format & itemsize of a 1-D
+
+    This is the Python 3 model, but will work on Python >= 2.6. Currently,
+    we use it only on >= 3.0.
+    """
+    cdef Py_buffer view
+    cdef int flags = PyBUF_SIMPLE
+    cdef int mode = 0
+    # cdef Py_ssize_t *shape, *strides, *suboffsets
+    
+    mode = check_buffer(obj)
+    if mode == 0:
+        raise TypeError("%r does not provide a buffer interface."%obj)
+
+    if mode == 3:
+        flags = PyBUF_ANY_CONTIGUOUS
+        if format:
+            flags |= PyBUF_FORMAT
+        PyObject_GetBuffer(obj, &view, flags)
+        assert view.ndim <= 1, "Can only reinterpret 1-D memoryviews"
+        assert view.len % itemsize == 0, "Buffer of length %i not divisible into items of size %i"%(view.len, itemsize)
+        # hack the format
+        view.ndim = 1
+        view.format = format
+        view.itemsize = itemsize
+        view.strides = <Py_ssize_t *>malloc(sizeof(Py_ssize_t))
+        view.strides[0] = itemsize
+        view.shape = <Py_ssize_t *>malloc(sizeof(Py_ssize_t))
+        view.shape[0] = view.len/itemsize
+        view.suboffsets = <Py_ssize_t *>malloc(sizeof(Py_ssize_t))
+        view.suboffsets[0] = 0
+        # for debug: make buffer writable, for zero-copy testing
+        # view.readonly = 0
+        
+        return PyMemoryView_FromBuffer(&view)
+    else:
+        raise TypeError("This funciton is only for new-style buffer objects.")
+
+def rebuffer(obj, format, itemsize):
+    """Change the itemsize of a memoryview.
+    
+    Only for 1D contiguous buffers.
+    """
+    return _rebuffer(obj, format, itemsize)
+
+def array_from_buffer(view, dtype, shape):
+    """Get a numpy array from a memoryview, regardless of the itemsize of the original
+    memoryview.  This is important, because pyzmq does not send memoryview shape data
+    over the wire, so we need to change the memoryview itemsize before calling
+    asarray.
+    """
+    import numpy
+    A = numpy.array([],dtype=dtype)
+    ref = viewfromobject(A,0)
+    fmt = ref.format.encode()
+    buf = viewfromobject(view, 0)
+    buf = _rebuffer(view, fmt, ref.itemsize)
+    return numpy.asarray(buf, dtype=dtype).reshape(shape)
+
+def print_view_info(obj):
+    """simple utility for printing info on a new-style buffer object"""
+    cdef Py_buffer view
+    cdef int flags = PyBUF_ANY_CONTIGUOUS|PyBUF_FORMAT
+    cdef int mode = 0
+    
+    mode = check_buffer(obj)
+    if mode == 0:
+        raise TypeError("%r does not provide a buffer interface."%obj)
+
+    if mode == 3:
+        PyObject_GetBuffer(obj, &view, flags)
+        print <size_t>view.buf, view.len, view.format, view.ndim,
+        if view.ndim:
+            if view.shape:
+                print view.shape[0],
+            if view.strides:
+                print view.strides[0],
+            if view.suboffsets:
+                print view.suboffsets[0],
+        print
+    
\ No newline at end of file
diff --git a/zmq/backend/cython/socket.pxd b/zmq/backend/cython/socket.pxd
new file mode 100644
index 0000000..b8a331e
--- /dev/null
+++ b/zmq/backend/cython/socket.pxd
@@ -0,0 +1,47 @@
+"""0MQ Socket class declaration."""
+
+#
+#    Copyright (c) 2010-2011 Brian E. Granger & Min Ragan-Kelley
+#
+#    This file is part of pyzmq.
+#
+#    pyzmq is free software; you can redistribute it and/or modify it under
+#    the terms of the Lesser GNU General Public License as published by
+#    the Free Software Foundation; either version 3 of the License, or
+#    (at your option) any later version.
+#
+#    pyzmq is distributed in the hope that it will be useful,
+#    but WITHOUT ANY WARRANTY; without even the implied warranty of
+#    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+#    Lesser GNU General Public License for more details.
+#
+#    You should have received a copy of the Lesser GNU General Public License
+#    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+#
+
+#-----------------------------------------------------------------------------
+# Imports
+#-----------------------------------------------------------------------------
+
+from context cimport Context
+
+#-----------------------------------------------------------------------------
+# Code
+#-----------------------------------------------------------------------------
+
+
+cdef class Socket:
+
+    cdef object __weakref__     # enable weakref
+    cdef void *handle           # The C handle for the underlying zmq object.
+    cdef bint _shadow           # whether the Socket is a shadow wrapper of another
+    # Hold on to a reference to the context to make sure it is not garbage
+    # collected until the socket it done with it.
+    cdef public Context context # The zmq Context object that owns this.
+    cdef public bint _closed    # bool property for a closed socket.
+    cdef int _pid               # the pid of the process which created me (for fork safety)
+
+    # cpdef methods for direct-cython access:
+    cpdef object send(self, object data, int flags=*, copy=*, track=*)
+    cpdef object recv(self, int flags=*, copy=*, track=*)
+
diff --git a/zmq/backend/cython/socket.pyx b/zmq/backend/cython/socket.pyx
new file mode 100644
index 0000000..9b9ec36
--- /dev/null
+++ b/zmq/backend/cython/socket.pyx
@@ -0,0 +1,672 @@
+"""0MQ Socket class."""
+
+#
+#    Copyright (c) 2010-2011 Brian E. Granger & Min Ragan-Kelley
+#
+#    This file is part of pyzmq.
+#
+#    pyzmq is free software; you can redistribute it and/or modify it under
+#    the terms of the Lesser GNU General Public License as published by
+#    the Free Software Foundation; either version 3 of the License, or
+#    (at your option) any later version.
+#
+#    pyzmq is distributed in the hope that it will be useful,
+#    but WITHOUT ANY WARRANTY; without even the implied warranty of
+#    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+#    Lesser GNU General Public License for more details.
+#
+#    You should have received a copy of the Lesser GNU General Public License
+#    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+#
+
+#-----------------------------------------------------------------------------
+# Cython Imports
+#-----------------------------------------------------------------------------
+
+# get version-independent aliases:
+cdef extern from "pyversion_compat.h":
+    pass
+
+from libc.errno cimport ENAMETOOLONG
+from libc.string cimport memcpy
+
+from cpython cimport PyBytes_FromStringAndSize
+from cpython cimport PyBytes_AsString, PyBytes_Size
+from cpython cimport Py_DECREF, Py_INCREF
+
+from buffers cimport asbuffer_r, viewfromobject_r
+
+from libzmq cimport *
+from message cimport Frame, copy_zmq_msg_bytes
+
+from context cimport Context
+
+cdef extern from "Python.h":
+    ctypedef int Py_ssize_t
+
+cdef extern from "ipcmaxlen.h":
+    int get_ipc_path_max_len()
+
+cdef extern from "getpid_compat.h":
+    int getpid()
+
+
+#-----------------------------------------------------------------------------
+# Python Imports
+#-----------------------------------------------------------------------------
+
+import copy as copy_mod
+import time
+import sys
+import random
+import struct
+import codecs
+
+from zmq.utils import jsonapi
+
+try:
+    import cPickle
+    pickle = cPickle
+except:
+    cPickle = None
+    import pickle
+
+import zmq
+from zmq.backend.cython import constants
+from zmq.backend.cython.constants import *
+from zmq.backend.cython.checkrc cimport _check_rc
+from zmq.error import ZMQError, ZMQBindError, _check_version
+from zmq.utils.strtypes import bytes,unicode,basestring
+
+#-----------------------------------------------------------------------------
+# Code
+#-----------------------------------------------------------------------------
+
+IPC_PATH_MAX_LEN = get_ipc_path_max_len()
+
+# inline some small socket submethods:
+# true methods frequently cannot be inlined, acc. Cython docs
+
+cdef inline _check_closed(Socket s):
+    """raise ENOTSUP if socket is closed
+    
+    Does not do a deep check
+    """
+    if s._closed:
+        raise ZMQError(ENOTSOCK)
+
+cdef inline _check_closed_deep(Socket s):
+    """thorough check of whether the socket has been closed,
+    even if by another entity (e.g. ctx.destroy).
+    
+    Only used by the `closed` property.
+    
+    returns True if closed, False otherwise
+    """
+    cdef int rc
+    cdef int errno
+    cdef int stype
+    cdef size_t sz=sizeof(int)
+    if s._closed:
+        return True
+    else:
+        rc = zmq_getsockopt(s.handle, ZMQ_TYPE, <void *>&stype, &sz)
+        if rc < 0 and zmq_errno() == ENOTSOCK:
+            s._closed = True
+            return True
+        else:
+            _check_rc(rc)
+    return False
+
+cdef inline Frame _recv_frame(void *handle, int flags=0, track=False):
+    """Receive a message in a non-copying manner and return a Frame."""
+    cdef int rc
+    msg = zmq.Frame(track=track)
+    cdef Frame cmsg = msg
+
+    with nogil:
+        rc = zmq_msg_recv(&cmsg.zmq_msg, handle, flags)
+    
+    _check_rc(rc)
+    return msg
+
+cdef inline object _recv_copy(void *handle, int flags=0):
+    """Receive a message and return a copy"""
+    cdef zmq_msg_t zmq_msg
+    with nogil:
+        zmq_msg_init (&zmq_msg)
+        rc = zmq_msg_recv(&zmq_msg, handle, flags)
+    _check_rc(rc)
+    msg_bytes = copy_zmq_msg_bytes(&zmq_msg)
+    zmq_msg_close(&zmq_msg)
+    return msg_bytes
+
+cdef inline object _send_frame(void *handle, Frame msg, int flags=0):
+    """Send a Frame on this socket in a non-copy manner."""
+    cdef int rc
+    cdef Frame msg_copy
+
+    # Always copy so the original message isn't garbage collected.
+    # This doesn't do a real copy, just a reference.
+    msg_copy = msg.fast_copy()
+
+    with nogil:
+        rc = zmq_msg_send(&msg_copy.zmq_msg, handle, flags)
+
+    _check_rc(rc)
+    return msg.tracker
+
+
+cdef inline object _send_copy(void *handle, object msg, int flags=0):
+    """Send a message on this socket by copying its content."""
+    cdef int rc, rc2
+    cdef zmq_msg_t data
+    cdef char *msg_c
+    cdef Py_ssize_t msg_c_len=0
+
+    # copy to c array:
+    asbuffer_r(msg, <void **>&msg_c, &msg_c_len)
+
+    # Copy the msg before sending. This avoids any complications with
+    # the GIL, etc.
+    # If zmq_msg_init_* fails we must not call zmq_msg_close (Bus Error)
+    rc = zmq_msg_init_size(&data, msg_c_len)
+
+    _check_rc(rc)
+
+    with nogil:
+        memcpy(zmq_msg_data(&data), msg_c, zmq_msg_size(&data))
+        rc = zmq_msg_send(&data, handle, flags)
+        rc2 = zmq_msg_close(&data)
+    _check_rc(rc)
+    _check_rc(rc2)
+
+
+cdef class Socket:
+    """Socket(context, socket_type)
+
+    A 0MQ socket.
+
+    These objects will generally be constructed via the socket() method of a Context object.
+    
+    Note: 0MQ Sockets are *not* threadsafe. **DO NOT** share them across threads.
+    
+    Parameters
+    ----------
+    context : Context
+        The 0MQ Context this Socket belongs to.
+    socket_type : int
+        The socket type, which can be any of the 0MQ socket types: 
+        REQ, REP, PUB, SUB, PAIR, DEALER, ROUTER, PULL, PUSH, XPUB, XSUB.
+    
+    See Also
+    --------
+    .Context.socket : method for creating a socket bound to a Context.
+    """
+    
+    # no-op for the signature
+    def __init__(self, context=None, socket_type=-1, shadow=0):
+        pass
+    
+    def __cinit__(self, Context context=None, int socket_type=-1, size_t shadow=0, *args, **kwargs):
+        cdef Py_ssize_t c_handle
+
+        self.handle = NULL
+        self.context = context
+        if shadow:
+            self._shadow = True
+            self.handle = <void *>shadow
+        else:
+            if context is None:
+                raise TypeError("context must be specified")
+            if socket_type < 0:
+                raise TypeError("socket_type must be specified")
+            self._shadow = False
+            self.handle = zmq_socket(context.handle, socket_type)
+        if self.handle == NULL:
+            raise ZMQError()
+        self._closed = False
+        self._pid = getpid()
+        if context:
+            context._add_socket(self.handle)
+
+    def __dealloc__(self):
+        """remove from context's list
+        
+        But be careful that context might not exist if called during gc
+        """
+        if self.handle != NULL and not self._shadow and getpid() == self._pid:
+            # during gc, self.context might be NULL
+            if self.context and not self.context.closed:
+                self.context._remove_socket(self.handle)
+    
+    @property
+    def underlying(self):
+        """The address of the underlying libzmq socket"""
+        return <size_t> self.handle
+    
+    @property
+    def closed(self):
+        return _check_closed_deep(self)
+    
+    def close(self, linger=None):
+        """s.close(linger=None)
+
+        Close the socket.
+        
+        If linger is specified, LINGER sockopt will be set prior to closing.
+
+        This can be called to close the socket by hand. If this is not
+        called, the socket will automatically be closed when it is
+        garbage collected.
+        """
+        cdef int rc=0
+        cdef int linger_c
+        cdef bint setlinger=False
+        
+        if linger is not None:
+            linger_c = linger
+            setlinger=True
+        
+        if self.handle != NULL and not self._closed and getpid() == self._pid:
+            if setlinger:
+                zmq_setsockopt(self.handle, ZMQ_LINGER, &linger_c, sizeof(int))
+            rc = zmq_close(self.handle)
+            if rc != 0 and zmq_errno() != ENOTSOCK:
+                # ignore ENOTSOCK (closed by Context)
+                _check_rc(rc)
+            self._closed = True
+            # during gc, self.context might be NULL
+            if self.context:
+                self.context._remove_socket(self.handle)
+            self.handle = NULL
+
+    def set(self, int option, optval):
+        """s.set(option, optval)
+
+        Set socket options.
+
+        See the 0MQ API documentation for details on specific options.
+
+        Parameters
+        ----------
+        option : int
+            The option to set.  Available values will depend on your
+            version of libzmq.  Examples include::
+            
+                zmq.SUBSCRIBE, UNSUBSCRIBE, IDENTITY, HWM, LINGER, FD
+        
+        optval : int or bytes
+            The value of the option to set.
+        """
+        cdef int64_t optval_int64_c
+        cdef int optval_int_c
+        cdef int rc
+        cdef char* optval_c
+        cdef Py_ssize_t sz
+
+        _check_closed(self)
+        if isinstance(optval, unicode):
+            raise TypeError("unicode not allowed, use setsockopt_string")
+
+        if option in zmq.constants.bytes_sockopts:
+            if not isinstance(optval, bytes):
+                raise TypeError('expected bytes, got: %r' % optval)
+            optval_c = PyBytes_AsString(optval)
+            sz = PyBytes_Size(optval)
+            rc = zmq_setsockopt(
+                    self.handle, option,
+                    optval_c, sz
+                )
+        elif option in zmq.constants.int64_sockopts:
+            if not isinstance(optval, int):
+                raise TypeError('expected int, got: %r' % optval)
+            optval_int64_c = optval
+            rc = zmq_setsockopt(
+                    self.handle, option,
+                    &optval_int64_c, sizeof(int64_t)
+                )
+        else:
+            # default is to assume int, which is what most new sockopts will be
+            # this lets pyzmq work with newer libzmq which may add constants
+            # pyzmq has not yet added, rather than artificially raising. Invalid
+            # sockopts will still raise just the same, but it will be libzmq doing
+            # the raising.
+            if not isinstance(optval, int):
+                raise TypeError('expected int, got: %r' % optval)
+            optval_int_c = optval
+            rc = zmq_setsockopt(
+                    self.handle, option,
+                    &optval_int_c, sizeof(int)
+                )
+
+        _check_rc(rc)
+
+    def get(self, int option):
+        """s.get(option)
+
+        Get the value of a socket option.
+
+        See the 0MQ API documentation for details on specific options.
+
+        Parameters
+        ----------
+        option : int
+            The option to get.  Available values will depend on your
+            version of libzmq.  Examples include::
+            
+                zmq.IDENTITY, HWM, LINGER, FD, EVENTS
+
+        Returns
+        -------
+        optval : int or bytes
+            The value of the option as a bytestring or int.
+        """
+        cdef int64_t optval_int64_c
+        cdef int optval_int_c
+        cdef fd_t optval_fd_c
+        cdef char identity_str_c [255]
+        cdef size_t sz
+        cdef int rc
+
+        _check_closed(self)
+
+        if option in zmq.constants.bytes_sockopts:
+            sz = 255
+            rc = zmq_getsockopt(self.handle, option, <void *>identity_str_c, &sz)
+            _check_rc(rc)
+            # strip null-terminated strings *except* identity
+            if option != ZMQ_IDENTITY and sz > 0 and (<char *>identity_str_c)[sz-1] == b'\0':
+                sz -= 1
+            result = PyBytes_FromStringAndSize(<char *>identity_str_c, sz)
+        elif option in zmq.constants.int64_sockopts:
+            sz = sizeof(int64_t)
+            rc = zmq_getsockopt(self.handle, option, <void *>&optval_int64_c, &sz)
+            _check_rc(rc)
+            result = optval_int64_c
+        elif option in zmq.constants.fd_sockopts:
+            sz = sizeof(fd_t)
+            rc = zmq_getsockopt(self.handle, option, <void *>&optval_fd_c, &sz)
+            _check_rc(rc)
+            result = optval_fd_c
+        else:
+            # default is to assume int, which is what most new sockopts will be
+            # this lets pyzmq work with newer libzmq which may add constants
+            # pyzmq has not yet added, rather than artificially raising. Invalid
+            # sockopts will still raise just the same, but it will be libzmq doing
+            # the raising.
+            sz = sizeof(int)
+            rc = zmq_getsockopt(self.handle, option, <void *>&optval_int_c, &sz)
+            _check_rc(rc)
+            result = optval_int_c
+
+        return result
+    
+    def bind(self, addr):
+        """s.bind(addr)
+
+        Bind the socket to an address.
+
+        This causes the socket to listen on a network port. Sockets on the
+        other side of this connection will use ``Socket.connect(addr)`` to
+        connect to this socket.
+
+        Parameters
+        ----------
+        addr : str
+            The address string. This has the form 'protocol://interface:port',
+            for example 'tcp://127.0.0.1:5555'. Protocols supported include
+            tcp, udp, pgm, epgm, inproc and ipc. If the address is unicode, it is
+            encoded to utf-8 first.
+        """
+        cdef int rc
+        cdef char* c_addr
+
+        _check_closed(self)
+        if isinstance(addr, unicode):
+            addr = addr.encode('utf-8')
+        if not isinstance(addr, bytes):
+            raise TypeError('expected str, got: %r' % addr)
+        c_addr = addr
+        rc = zmq_bind(self.handle, c_addr)
+        if rc != 0:
+            if IPC_PATH_MAX_LEN and zmq_errno() == ENAMETOOLONG:
+                # py3compat: addr is bytes, but msg wants str
+                if str is unicode:
+                    addr = addr.decode('utf-8', 'replace')
+                path = addr.split('://', 1)[-1]
+                msg = ('ipc path "{0}" is longer than {1} '
+                                'characters (sizeof(sockaddr_un.sun_path)). '
+                                'zmq.IPC_PATH_MAX_LEN constant can be used '
+                                'to check addr length (if it is defined).'
+                                .format(path, IPC_PATH_MAX_LEN))
+                raise ZMQError(msg=msg)
+        _check_rc(rc)
+
+    def connect(self, addr):
+        """s.connect(addr)
+
+        Connect to a remote 0MQ socket.
+
+        Parameters
+        ----------
+        addr : str
+            The address string. This has the form 'protocol://interface:port',
+            for example 'tcp://127.0.0.1:5555'. Protocols supported are
+            tcp, upd, pgm, inproc and ipc. If the address is unicode, it is
+            encoded to utf-8 first.
+        """
+        cdef int rc
+        cdef char* c_addr
+
+        _check_closed(self)
+        if isinstance(addr, unicode):
+            addr = addr.encode('utf-8')
+        if not isinstance(addr, bytes):
+            raise TypeError('expected str, got: %r' % addr)
+        c_addr = addr
+        
+        rc = zmq_connect(self.handle, c_addr)
+        if rc != 0:
+            raise ZMQError()
+
+    def unbind(self, addr):
+        """s.unbind(addr)
+        
+        Unbind from an address (undoes a call to bind).
+        
+        .. versionadded:: libzmq-3.2
+        .. versionadded:: 13.0
+
+        Parameters
+        ----------
+        addr : str
+            The address string. This has the form 'protocol://interface:port',
+            for example 'tcp://127.0.0.1:5555'. Protocols supported are
+            tcp, upd, pgm, inproc and ipc. If the address is unicode, it is
+            encoded to utf-8 first.
+        """
+        cdef int rc
+        cdef char* c_addr
+
+        _check_version((3,2), "unbind")
+        _check_closed(self)
+        if isinstance(addr, unicode):
+            addr = addr.encode('utf-8')
+        if not isinstance(addr, bytes):
+            raise TypeError('expected str, got: %r' % addr)
+        c_addr = addr
+        
+        rc = zmq_unbind(self.handle, c_addr)
+        if rc != 0:
+            raise ZMQError()
+
+    def disconnect(self, addr):
+        """s.disconnect(addr)
+
+        Disconnect from a remote 0MQ socket (undoes a call to connect).
+        
+        .. versionadded:: libzmq-3.2
+        .. versionadded:: 13.0
+
+        Parameters
+        ----------
+        addr : str
+            The address string. This has the form 'protocol://interface:port',
+            for example 'tcp://127.0.0.1:5555'. Protocols supported are
+            tcp, upd, pgm, inproc and ipc. If the address is unicode, it is
+            encoded to utf-8 first.
+        """
+        cdef int rc
+        cdef char* c_addr
+        
+        _check_version((3,2), "disconnect")
+        _check_closed(self)
+        if isinstance(addr, unicode):
+            addr = addr.encode('utf-8')
+        if not isinstance(addr, bytes):
+            raise TypeError('expected str, got: %r' % addr)
+        c_addr = addr
+        
+        rc = zmq_disconnect(self.handle, c_addr)
+        if rc != 0:
+            raise ZMQError()
+
+    def monitor(self, addr, int events=ZMQ_EVENT_ALL):
+        """s.monitor(addr, flags)
+
+        Start publishing socket events on inproc.
+        See libzmq docs for zmq_monitor for details.
+        
+        While this function is available from libzmq 3.2,
+        pyzmq cannot parse monitor messages from libzmq prior to 4.0.
+        
+        .. versionadded: libzmq-3.2
+        .. versionadded: 14.0
+        
+        Parameters
+        ----------
+        addr : str
+            The inproc url used for monitoring. Passing None as
+            the addr will cause an existing socket monitor to be
+            deregistered.
+        events : int [default: zmq.EVENT_ALL]
+            The zmq event bitmask for which events will be sent to the monitor.
+        """
+        cdef int rc, c_flags
+        cdef char* c_addr = NULL
+        
+        _check_version((3,2), "monitor")
+        if addr is not None:
+            if isinstance(addr, unicode):
+                addr = addr.encode('utf-8')
+            if not isinstance(addr, bytes):
+                raise TypeError('expected str, got: %r' % addr)
+            c_addr = addr
+        c_flags = events
+        rc = zmq_socket_monitor(self.handle, c_addr, c_flags)
+        _check_rc(rc)
+
+    #-------------------------------------------------------------------------
+    # Sending and receiving messages
+    #-------------------------------------------------------------------------
+
+    cpdef object send(self, object data, int flags=0, copy=True, track=False):
+        """s.send(data, flags=0, copy=True, track=False)
+
+        Send a message on this socket.
+
+        This queues the message to be sent by the IO thread at a later time.
+
+        Parameters
+        ----------
+        data : object, str, Frame
+            The content of the message.
+        flags : int
+            Any supported flag: NOBLOCK, SNDMORE.
+        copy : bool
+            Should the message be sent in a copying or non-copying manner.
+        track : bool
+            Should the message be tracked for notification that ZMQ has
+            finished with it? (ignored if copy=True)
+
+        Returns
+        -------
+        None : if `copy` or not track
+            None if message was sent, raises an exception otherwise.
+        MessageTracker : if track and not copy
+            a MessageTracker object, whose `pending` property will
+            be True until the send is completed.
+        
+        Raises
+        ------
+        TypeError
+            If a unicode object is passed
+        ValueError
+            If `track=True`, but an untracked Frame is passed.
+        ZMQError
+            If the send does not succeed for any reason.
+        
+        """
+        _check_closed(self)
+        
+        if isinstance(data, unicode):
+            raise TypeError("unicode not allowed, use send_string")
+        
+        if copy:
+            # msg.bytes never returns the input data object
+            # it is always a copy, but always the same copy
+            if isinstance(data, Frame):
+                data = data.buffer
+            return _send_copy(self.handle, data, flags)
+        else:
+            if isinstance(data, Frame):
+                if track and not data.tracker:
+                    raise ValueError('Not a tracked message')
+                msg = data
+            else:
+                msg = Frame(data, track=track)
+            return _send_frame(self.handle, msg, flags)
+
+    cpdef object recv(self, int flags=0, copy=True, track=False):
+        """s.recv(flags=0, copy=True, track=False)
+
+        Receive a message.
+
+        Parameters
+        ----------
+        flags : int
+            Any supported flag: NOBLOCK. If NOBLOCK is set, this method
+            will raise a ZMQError with EAGAIN if a message is not ready.
+            If NOBLOCK is not set, then this method will block until a
+            message arrives.
+        copy : bool
+            Should the message be received in a copying or non-copying manner?
+            If False a Frame object is returned, if True a string copy of
+            message is returned.
+        track : bool
+            Should the message be tracked for notification that ZMQ has
+            finished with it? (ignored if copy=True)
+
+        Returns
+        -------
+        msg : bytes, Frame
+            The received message frame.  If `copy` is False, then it will be a Frame,
+            otherwise it will be bytes.
+            
+        Raises
+        ------
+        ZMQError
+            for any of the reasons zmq_msg_recv might fail.
+        """
+        _check_closed(self)
+        
+        if copy:
+            return _recv_copy(self.handle, flags)
+        else:
+            frame = _recv_frame(self.handle, flags, track)
+            frame.more = self.getsockopt(zmq.RCVMORE)
+            return frame
+    
+
+__all__ = ['Socket', 'IPC_PATH_MAX_LEN']
diff --git a/zmq/backend/cython/utils.pxd b/zmq/backend/cython/utils.pxd
new file mode 100644
index 0000000..1d7117f
--- /dev/null
+++ b/zmq/backend/cython/utils.pxd
@@ -0,0 +1,29 @@
+"""Wrap zmq_utils.h"""
+
+#
+#    Copyright (c) 2010 Brian E. Granger & Min Ragan-Kelley
+#
+#    This file is part of pyzmq.
+#
+#    pyzmq is free software; you can redistribute it and/or modify it under
+#    the terms of the Lesser GNU General Public License as published by
+#    the Free Software Foundation; either version 3 of the License, or
+#    (at your option) any later version.
+#
+#    pyzmq is distributed in the hope that it will be useful,
+#    but WITHOUT ANY WARRANTY; without even the implied warranty of
+#    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+#    Lesser GNU General Public License for more details.
+#
+#    You should have received a copy of the Lesser GNU General Public License
+#    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+#
+
+#-----------------------------------------------------------------------------
+# Code
+#-----------------------------------------------------------------------------
+
+
+cdef class Stopwatch:
+    cdef void *watch # The C handle for the underlying zmq object
+
diff --git a/zmq/backend/cython/utils.pyx b/zmq/backend/cython/utils.pyx
new file mode 100644
index 0000000..68976e3
--- /dev/null
+++ b/zmq/backend/cython/utils.pyx
@@ -0,0 +1,119 @@
+"""0MQ utils."""
+
+#
+#    Copyright (c) 2010-2011 Brian E. Granger & Min Ragan-Kelley
+#
+#    This file is part of pyzmq.
+#
+#    pyzmq is free software; you can redistribute it and/or modify it under
+#    the terms of the Lesser GNU General Public License as published by
+#    the Free Software Foundation; either version 3 of the License, or
+#    (at your option) any later version.
+#
+#    pyzmq is distributed in the hope that it will be useful,
+#    but WITHOUT ANY WARRANTY; without even the implied warranty of
+#    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+#    Lesser GNU General Public License for more details.
+#
+#    You should have received a copy of the Lesser GNU General Public License
+#    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+#
+
+from libzmq cimport (
+    zmq_stopwatch_start, zmq_stopwatch_stop, zmq_sleep, zmq_curve_keypair,
+    zmq_has, const_char_ptr
+)
+from zmq.error import ZMQError, _check_rc, _check_version
+from zmq.utils.strtypes import unicode
+
+def has(capability):
+    """Check for zmq capability by name (e.g. 'ipc', 'curve')
+    
+    .. versionadded:: libzmq-4.1
+    .. versionadded:: 14.1
+    """
+    _check_version((4,1), 'zmq.has')
+    cdef bytes ccap
+    if isinstance(capability, unicode):
+        capability = capability.encode('utf8')
+    ccap = capability
+    return bool(zmq_has(ccap))
+
+def curve_keypair():
+    """generate a Z85 keypair for use with zmq.CURVE security
+    
+    Requires libzmq (≥ 4.0) to have been linked with libsodium.
+    
+    .. versionadded:: libzmq-4.0
+    .. versionadded:: 14.0
+    
+    Returns
+    -------
+    (public, secret) : two bytestrings
+        The public and private keypair as 40 byte z85-encoded bytestrings.
+    """
+    cdef int rc
+    cdef char[64] public_key
+    cdef char[64] secret_key
+    _check_version((4,0), "curve_keypair")
+    rc = zmq_curve_keypair (public_key, secret_key)
+    _check_rc(rc)
+    return public_key, secret_key
+
+
+cdef class Stopwatch:
+    """Stopwatch()
+
+    A simple stopwatch based on zmq_stopwatch_start/stop.
+
+    This class should be used for benchmarking and timing 0MQ code.
+    """
+
+    def __cinit__(self):
+        self.watch = NULL
+
+    def __dealloc__(self):
+        # copy of self.stop() we can't call object methods in dealloc as it
+        # might already be partially deleted
+        if self.watch:
+            zmq_stopwatch_stop(self.watch)
+            self.watch = NULL
+
+    def start(self):
+        """s.start()
+
+        Start the stopwatch.
+        """
+        if self.watch == NULL:
+            self.watch = zmq_stopwatch_start()
+        else:
+            raise ZMQError('Stopwatch is already running.')
+
+    def stop(self):
+        """s.stop()
+
+        Stop the stopwatch.
+        
+        Returns
+        -------
+        t : unsigned long int
+            the number of microseconds since ``start()`` was called.
+        """
+        cdef unsigned long time
+        if self.watch == NULL:
+            raise ZMQError('Must start the Stopwatch before calling stop.')
+        else:
+            time = zmq_stopwatch_stop(self.watch)
+            self.watch = NULL
+            return time
+
+    def sleep(self, int seconds):
+        """s.sleep(seconds)
+
+        Sleep for an integer number of seconds.
+        """
+        with nogil:
+            zmq_sleep(seconds)
+
+
+__all__ = ['has', 'curve_keypair', 'Stopwatch']
diff --git a/zmq/backend/select.py b/zmq/backend/select.py
new file mode 100644
index 0000000..0a2e09a
--- /dev/null
+++ b/zmq/backend/select.py
@@ -0,0 +1,39 @@
+"""Import basic exposure of libzmq C API as a backend"""
+
+# Copyright (C) PyZMQ Developers
+# Distributed under the terms of the Modified BSD License.
+
+public_api = [
+    'Context',
+    'Socket',
+    'Frame',
+    'Message',
+    'Stopwatch',
+    'device',
+    'proxy',
+    'zmq_poll',
+    'strerror',
+    'zmq_errno',
+    'has',
+    'curve_keypair',
+    'constants',
+    'zmq_version_info',
+    'IPC_PATH_MAX_LEN',
+]
+
+def select_backend(name):
+    """Select the pyzmq backend"""
+    try:
+        mod = __import__(name, fromlist=public_api)
+    except ImportError:
+        raise
+    except Exception as e:
+        import sys
+        from zmq.utils.sixcerpt import reraise
+        exc_info = sys.exc_info()
+        reraise(ImportError, ImportError("Importing %s failed with %s" % (name, e)), exc_info[2])
+    
+    ns = {}
+    for key in public_api:
+        ns[key] = getattr(mod, key)
+    return ns
diff --git a/zmq/devices/__init__.py b/zmq/devices/__init__.py
new file mode 100644
index 0000000..2371596
--- /dev/null
+++ b/zmq/devices/__init__.py
@@ -0,0 +1,16 @@
+"""0MQ Device classes for running in background threads or processes."""
+
+# Copyright (C) PyZMQ Developers
+# Distributed under the terms of the Modified BSD License.
+
+from zmq import device
+from zmq.devices import basedevice, proxydevice, monitoredqueue, monitoredqueuedevice
+
+from zmq.devices.basedevice import *
+from zmq.devices.proxydevice import *
+from zmq.devices.monitoredqueue import *
+from zmq.devices.monitoredqueuedevice import *
+
+__all__ = ['device']
+for submod in (basedevice, proxydevice, monitoredqueue, monitoredqueuedevice):
+    __all__.extend(submod.__all__)
diff --git a/zmq/devices/basedevice.py b/zmq/devices/basedevice.py
new file mode 100644
index 0000000..7ba1b7a
--- /dev/null
+++ b/zmq/devices/basedevice.py
@@ -0,0 +1,229 @@
+"""Classes for running 0MQ Devices in the background."""
+
+# Copyright (C) PyZMQ Developers
+# Distributed under the terms of the Modified BSD License.
+
+
+import time
+from threading import Thread
+from multiprocessing import Process
+
+from zmq import device, QUEUE, Context, ETERM, ZMQError
+
+
+class Device:
+    """A 0MQ Device to be run in the background.
+    
+    You do not pass Socket instances to this, but rather Socket types::
+
+        Device(device_type, in_socket_type, out_socket_type)
+
+    For instance::
+
+        dev = Device(zmq.QUEUE, zmq.DEALER, zmq.ROUTER)
+
+    Similar to zmq.device, but socket types instead of sockets themselves are
+    passed, and the sockets are created in the work thread, to avoid issues
+    with thread safety. As a result, additional bind_{in|out} and
+    connect_{in|out} methods and setsockopt_{in|out} allow users to specify
+    connections for the sockets.
+    
+    Parameters
+    ----------
+    device_type : int
+        The 0MQ Device type
+    {in|out}_type : int
+        zmq socket types, to be passed later to context.socket(). e.g.
+        zmq.PUB, zmq.SUB, zmq.REQ. If out_type is < 0, then in_socket is used
+        for both in_socket and out_socket.
+        
+    Methods
+    -------
+    bind_{in_out}(iface)
+        passthrough for ``{in|out}_socket.bind(iface)``, to be called in the thread
+    connect_{in_out}(iface)
+        passthrough for ``{in|out}_socket.connect(iface)``, to be called in the
+        thread
+    setsockopt_{in_out}(opt,value)
+        passthrough for ``{in|out}_socket.setsockopt(opt, value)``, to be called in
+        the thread
+    
+    Attributes
+    ----------
+    daemon : int
+        sets whether the thread should be run as a daemon
+        Default is true, because if it is false, the thread will not
+        exit unless it is killed
+    context_factory : callable (class attribute)
+        Function for creating the Context. This will be Context.instance
+        in ThreadDevices, and Context in ProcessDevices.  The only reason
+        it is not instance() in ProcessDevices is that there may be a stale
+        Context instance already initialized, and the forked environment
+        should *never* try to use it.
+    """
+    
+    context_factory = Context.instance
+    """Callable that returns a context. Typically either Context.instance or Context,
+    depending on whether the device should share the global instance or not.
+    """
+
+    def __init__(self, device_type=QUEUE, in_type=None, out_type=None):
+        self.device_type = device_type
+        if in_type is None:
+            raise TypeError("in_type must be specified")
+        if out_type is None:
+            raise TypeError("out_type must be specified")
+        self.in_type = in_type
+        self.out_type = out_type
+        self._in_binds = []
+        self._in_connects = []
+        self._in_sockopts = []
+        self._out_binds = []
+        self._out_connects = []
+        self._out_sockopts = []
+        self.daemon = True
+        self.done = False
+    
+    def bind_in(self, addr):
+        """Enqueue ZMQ address for binding on in_socket.
+
+        See zmq.Socket.bind for details.
+        """
+        self._in_binds.append(addr)
+    
+    def connect_in(self, addr):
+        """Enqueue ZMQ address for connecting on in_socket.
+
+        See zmq.Socket.connect for details.
+        """
+        self._in_connects.append(addr)
+    
+    def setsockopt_in(self, opt, value):
+        """Enqueue setsockopt(opt, value) for in_socket
+
+        See zmq.Socket.setsockopt for details.
+        """
+        self._in_sockopts.append((opt, value))
+    
+    def bind_out(self, addr):
+        """Enqueue ZMQ address for binding on out_socket.
+
+        See zmq.Socket.bind for details.
+        """
+        self._out_binds.append(addr)
+    
+    def connect_out(self, addr):
+        """Enqueue ZMQ address for connecting on out_socket.
+
+        See zmq.Socket.connect for details.
+        """
+        self._out_connects.append(addr)
+    
+    def setsockopt_out(self, opt, value):
+        """Enqueue setsockopt(opt, value) for out_socket
+
+        See zmq.Socket.setsockopt for details.
+        """
+        self._out_sockopts.append((opt, value))
+    
+    def _setup_sockets(self):
+        ctx = self.context_factory()
+        
+        self._context = ctx
+        
+        # create the sockets
+        ins = ctx.socket(self.in_type)
+        if self.out_type < 0:
+            outs = ins
+        else:
+            outs = ctx.socket(self.out_type)
+        
+        # set sockopts (must be done first, in case of zmq.IDENTITY)
+        for opt,value in self._in_sockopts:
+            ins.setsockopt(opt, value)
+        for opt,value in self._out_sockopts:
+            outs.setsockopt(opt, value)
+        
+        for iface in self._in_binds:
+            ins.bind(iface)
+        for iface in self._out_binds:
+            outs.bind(iface)
+        
+        for iface in self._in_connects:
+            ins.connect(iface)
+        for iface in self._out_connects:
+            outs.connect(iface)
+        
+        return ins,outs
+    
+    def run_device(self):
+        """The runner method.
+
+        Do not call me directly, instead call ``self.start()``, just like a Thread.
+        """
+        ins,outs = self._setup_sockets()
+        device(self.device_type, ins, outs)
+    
+    def run(self):
+        """wrap run_device in try/catch ETERM"""
+        try:
+            self.run_device()
+        except ZMQError as e:
+            if e.errno == ETERM:
+                # silence TERM errors, because this should be a clean shutdown
+                pass
+            else:
+                raise
+        finally:
+            self.done = True
+    
+    def start(self):
+        """Start the device. Override me in subclass for other launchers."""
+        return self.run()
+
+    def join(self,timeout=None):
+        """wait for me to finish, like Thread.join.
+        
+        Reimplemented appropriately by subclasses."""
+        tic = time.time()
+        toc = tic
+        while not self.done and not (timeout is not None and toc-tic > timeout):
+            time.sleep(.001)
+            toc = time.time()
+
+
+class BackgroundDevice(Device):
+    """Base class for launching Devices in background processes and threads."""
+
+    launcher=None
+    _launch_class=None
+
+    def start(self):
+        self.launcher = self._launch_class(target=self.run)
+        self.launcher.daemon = self.daemon
+        return self.launcher.start()
+
+    def join(self, timeout=None):
+        return self.launcher.join(timeout=timeout)
+
+
+class ThreadDevice(BackgroundDevice):
+    """A Device that will be run in a background Thread.
+
+    See Device for details.
+    """
+    _launch_class=Thread
+
+class ProcessDevice(BackgroundDevice):
+    """A Device that will be run in a background Process.
+
+    See Device for details.
+    """
+    _launch_class=Process
+    context_factory = Context
+    """Callable that returns a context. Typically either Context.instance or Context,
+    depending on whether the device should share the global instance or not.
+    """
+
+
+__all__ = ['Device', 'ThreadDevice', 'ProcessDevice']
diff --git a/zmq/devices/monitoredqueue.pxd b/zmq/devices/monitoredqueue.pxd
new file mode 100644
index 0000000..1e26ed8
--- /dev/null
+++ b/zmq/devices/monitoredqueue.pxd
@@ -0,0 +1,177 @@
+"""MonitoredQueue class declarations.
+
+Authors
+-------
+* MinRK
+* Brian Granger
+"""
+
+#
+#    Copyright (c) 2010 Min Ragan-Kelley, Brian Granger
+#
+#    This file is part of pyzmq, but is derived and adapted from zmq_queue.cpp
+#    originally from libzmq-2.1.6, used under LGPLv3
+#
+#    pyzmq is free software; you can redistribute it and/or modify it under
+#    the terms of the Lesser GNU General Public License as published by
+#    the Free Software Foundation; either version 3 of the License, or
+#    (at your option) any later version.
+#
+#    pyzmq is distributed in the hope that it will be useful,
+#    but WITHOUT ANY WARRANTY; without even the implied warranty of
+#    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+#    Lesser GNU General Public License for more details.
+#
+#    You should have received a copy of the Lesser GNU General Public License
+#    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+#
+
+#-----------------------------------------------------------------------------
+# Imports
+#-----------------------------------------------------------------------------
+
+from libzmq cimport *
+
+#-----------------------------------------------------------------------------
+# MonitoredQueue C functions
+#-----------------------------------------------------------------------------
+
+cdef inline int _relay(void *insocket_, void *outsocket_, void *sidesocket_, 
+                zmq_msg_t msg, zmq_msg_t side_msg, zmq_msg_t id_msg,
+                bint swap_ids) nogil:
+    cdef int rc
+    cdef int64_t flag_2
+    cdef int flag_3
+    cdef int flags
+    cdef bint more
+    cdef size_t flagsz
+    cdef void * flag_ptr
+    
+    if ZMQ_VERSION_MAJOR < 3:
+        flagsz = sizeof (int64_t)
+        flag_ptr = &flag_2
+    else:
+        flagsz = sizeof (int)
+        flag_ptr = &flag_3
+    
+    if swap_ids:# both router, must send second identity first
+        # recv two ids into msg, id_msg
+        rc = zmq_msg_recv(&msg, insocket_, 0)
+        if rc < 0: return rc
+        
+        rc = zmq_msg_recv(&id_msg, insocket_, 0)
+        if rc < 0: return rc
+
+        # send second id (id_msg) first
+        #!!!! always send a copy before the original !!!!
+        rc = zmq_msg_copy(&side_msg, &id_msg)
+        if rc < 0: return rc
+        rc = zmq_msg_send(&side_msg, outsocket_, ZMQ_SNDMORE)
+        if rc < 0: return rc
+        rc = zmq_msg_send(&id_msg, sidesocket_, ZMQ_SNDMORE)
+        if rc < 0: return rc
+        # send first id (msg) second
+        rc = zmq_msg_copy(&side_msg, &msg)
+        if rc < 0: return rc
+        rc = zmq_msg_send(&side_msg, outsocket_, ZMQ_SNDMORE)
+        if rc < 0: return rc
+        rc = zmq_msg_send(&msg, sidesocket_, ZMQ_SNDMORE)
+        if rc < 0: return rc
+    while (True):
+        rc = zmq_msg_recv(&msg, insocket_, 0)
+        if rc < 0: return rc
+        # assert (rc == 0)
+        rc = zmq_getsockopt (insocket_, ZMQ_RCVMORE, flag_ptr, &flagsz)
+        if rc < 0: return rc
+        flags = 0
+        if ZMQ_VERSION_MAJOR < 3:
+            if flag_2:
+                flags |= ZMQ_SNDMORE
+        else:
+            if flag_3:
+                flags |= ZMQ_SNDMORE
+            # LABEL has been removed:
+            # rc = zmq_getsockopt (insocket_, ZMQ_RCVLABEL, flag_ptr, &flagsz)
+            # if flag_3:
+            #     flags |= ZMQ_SNDLABEL
+        # assert (rc == 0)
+
+        rc = zmq_msg_copy(&side_msg, &msg)
+        if rc < 0: return rc
+        if flags:
+            rc = zmq_msg_send(&side_msg, outsocket_, flags)
+            if rc < 0: return rc
+            # only SNDMORE for side-socket
+            rc = zmq_msg_send(&msg, sidesocket_, ZMQ_SNDMORE)
+            if rc < 0: return rc
+        else:
+            rc = zmq_msg_send(&side_msg, outsocket_, 0)
+            if rc < 0: return rc
+            rc = zmq_msg_send(&msg, sidesocket_, 0)
+            if rc < 0: return rc
+            break
+    return rc
+
+# the MonitoredQueue C function, adapted from zmq::queue.cpp :
+cdef inline int c_monitored_queue (void *insocket_, void *outsocket_,
+                        void *sidesocket_, zmq_msg_t *in_msg_ptr, 
+                        zmq_msg_t *out_msg_ptr, int swap_ids) nogil:
+    """The actual C function for a monitored queue device. 
+
+    See ``monitored_queue()`` for details.
+    """
+    
+    cdef zmq_msg_t msg
+    cdef int rc = zmq_msg_init (&msg)
+    cdef zmq_msg_t id_msg
+    rc = zmq_msg_init (&id_msg)
+    if rc < 0: return rc
+    cdef zmq_msg_t side_msg
+    rc = zmq_msg_init (&side_msg)
+    if rc < 0: return rc
+    
+    cdef zmq_pollitem_t items [2]
+    items [0].socket = insocket_
+    items [0].fd = 0
+    items [0].events = ZMQ_POLLIN
+    items [0].revents = 0
+    items [1].socket = outsocket_
+    items [1].fd = 0
+    items [1].events = ZMQ_POLLIN
+    items [1].revents = 0
+    # I don't think sidesocket should be polled?
+    # items [2].socket = sidesocket_
+    # items [2].fd = 0
+    # items [2].events = ZMQ_POLLIN
+    # items [2].revents = 0
+    
+    while (True):
+    
+        # //  Wait while there are either requests or replies to process.
+        rc = zmq_poll (&items [0], 2, -1)
+        if rc < 0: return rc
+        # //  The algorithm below asumes ratio of request and replies processed
+        # //  under full load to be 1:1. Although processing requests replies
+        # //  first is tempting it is suspectible to DoS attacks (overloading
+        # //  the system with unsolicited replies).
+        # 
+        # //  Process a request.
+        if (items [0].revents & ZMQ_POLLIN):
+            # send in_prefix to side socket
+            rc = zmq_msg_copy(&side_msg, in_msg_ptr)
+            if rc < 0: return rc
+            rc = zmq_msg_send(&side_msg, sidesocket_, ZMQ_SNDMORE)
+            if rc < 0: return rc
+            # relay the rest of the message
+            rc = _relay(insocket_, outsocket_, sidesocket_, msg, side_msg, id_msg, swap_ids)
+            if rc < 0: return rc
+        if (items [1].revents & ZMQ_POLLIN):
+            # send out_prefix to side socket
+            rc = zmq_msg_copy(&side_msg, out_msg_ptr)
+            if rc < 0: return rc
+            rc = zmq_msg_send(&side_msg, sidesocket_, ZMQ_SNDMORE)
+            if rc < 0: return rc
+            # relay the rest of the message
+            rc = _relay(outsocket_, insocket_, sidesocket_, msg, side_msg, id_msg, swap_ids)
+            if rc < 0: return rc
+    return rc
diff --git a/zmq/devices/monitoredqueue.py b/zmq/devices/monitoredqueue.py
new file mode 100644
index 0000000..c6d9142
--- /dev/null
+++ b/zmq/devices/monitoredqueue.py
@@ -0,0 +1,37 @@
+"""pure Python monitored_queue function
+
+For use when Cython extension is unavailable (PyPy).
+
+Authors
+-------
+* MinRK
+"""
+
+# Copyright (C) PyZMQ Developers
+# Distributed under the terms of the Modified BSD License.
+
+import zmq
+
+def _relay(ins, outs, sides, prefix, swap_ids):
+    msg = ins.recv_multipart()
+    if swap_ids:
+        msg[:2] = msg[:2][::-1]
+    outs.send_multipart(msg)
+    sides.send_multipart([prefix] + msg)
+
+def monitored_queue(in_socket, out_socket, mon_socket,
+                    in_prefix=b'in', out_prefix=b'out'):
+    
+    swap_ids = in_socket.type == zmq.ROUTER and out_socket.type == zmq.ROUTER
+    
+    poller = zmq.Poller()
+    poller.register(in_socket, zmq.POLLIN)
+    poller.register(out_socket, zmq.POLLIN)
+    while True:
+        events = dict(poller.poll())
+        if in_socket in events:
+            _relay(in_socket, out_socket, mon_socket, in_prefix, swap_ids)
+        if out_socket in events:
+            _relay(out_socket, in_socket, mon_socket, out_prefix, swap_ids)
+
+__all__ = ['monitored_queue']
diff --git a/zmq/devices/monitoredqueue.pyx b/zmq/devices/monitoredqueue.pyx
new file mode 100644
index 0000000..d5fec64
--- /dev/null
+++ b/zmq/devices/monitoredqueue.pyx
@@ -0,0 +1,103 @@
+"""MonitoredQueue classes and functions.
+
+Authors
+-------
+* MinRK
+* Brian Granger
+"""
+
+#-----------------------------------------------------------------------------
+#  Copyright (c) 2010-2012 Brian Granger, Min Ragan-Kelley
+#
+#  This file is part of pyzmq
+#
+#  Distributed under the terms of the New BSD License.  The full license is in
+#  the file COPYING.BSD, distributed as part of this software.
+#-----------------------------------------------------------------------------
+
+#-----------------------------------------------------------------------------
+# Imports
+#-----------------------------------------------------------------------------
+
+cdef extern from "Python.h":
+    ctypedef int Py_ssize_t
+
+from libc.string cimport memcpy
+
+from buffers cimport asbuffer_r
+from libzmq cimport *
+
+from zmq.backend.cython.socket cimport Socket
+from zmq.backend.cython.checkrc cimport _check_rc
+
+from zmq import ROUTER, ZMQError
+
+#-----------------------------------------------------------------------------
+# MonitoredQueue functions
+#-----------------------------------------------------------------------------
+
+
+def monitored_queue(Socket in_socket, Socket out_socket, Socket mon_socket,
+                    bytes in_prefix=b'in', bytes out_prefix=b'out'):
+    """monitored_queue(in_socket, out_socket, mon_socket,
+                       in_prefix=b'in', out_prefix=b'out')
+    
+    Start a monitored queue device.
+    
+    A monitored queue is very similar to the zmq.proxy device (monitored queue came first).
+    
+    Differences from zmq.proxy:
+    
+    - monitored_queue supports both in and out being ROUTER sockets
+      (via swapping IDENTITY prefixes).
+    - monitor messages are prefixed, making in and out messages distinguishable.
+    
+    Parameters
+    ----------
+    in_socket : Socket
+        One of the sockets to the Queue. Its messages will be prefixed with
+        'in'.
+    out_socket : Socket
+        One of the sockets to the Queue. Its messages will be prefixed with
+        'out'. The only difference between in/out socket is this prefix.
+    mon_socket : Socket
+        This socket sends out every message received by each of the others
+        with an in/out prefix specifying which one it was.
+    in_prefix : str
+        Prefix added to broadcast messages from in_socket.
+    out_prefix : str
+        Prefix added to broadcast messages from out_socket.
+    """
+    
+    cdef void *ins=in_socket.handle
+    cdef void *outs=out_socket.handle
+    cdef void *mons=mon_socket.handle
+    cdef zmq_msg_t in_msg
+    cdef zmq_msg_t out_msg
+    cdef bint swap_ids
+    cdef char *msg_c = NULL
+    cdef Py_ssize_t msg_c_len
+    cdef int rc
+
+    # force swap_ids if both ROUTERs
+    swap_ids = (in_socket.type == ROUTER and out_socket.type == ROUTER)
+    
+    # build zmq_msg objects from str prefixes
+    asbuffer_r(in_prefix, <void **>&msg_c, &msg_c_len)
+    rc = zmq_msg_init_size(&in_msg, msg_c_len)
+    _check_rc(rc)
+    
+    memcpy(zmq_msg_data(&in_msg), msg_c, zmq_msg_size(&in_msg))
+    
+    asbuffer_r(out_prefix, <void **>&msg_c, &msg_c_len)
+    
+    rc = zmq_msg_init_size(&out_msg, msg_c_len)
+    _check_rc(rc)
+    
+    with nogil:
+        memcpy(zmq_msg_data(&out_msg), msg_c, zmq_msg_size(&out_msg))
+        rc = c_monitored_queue(ins, outs, mons, &in_msg, &out_msg, swap_ids)
+    _check_rc(rc)
+    return rc
+
+__all__ = ['monitored_queue']
diff --git a/zmq/devices/monitoredqueuedevice.py b/zmq/devices/monitoredqueuedevice.py
new file mode 100644
index 0000000..9723f86
--- /dev/null
+++ b/zmq/devices/monitoredqueuedevice.py
@@ -0,0 +1,66 @@
+"""MonitoredQueue classes and functions."""
+
+# Copyright (C) PyZMQ Developers
+# Distributed under the terms of the Modified BSD License.
+
+
+from zmq import ZMQError, PUB
+from zmq.devices.proxydevice import ProxyBase, Proxy, ThreadProxy, ProcessProxy
+from zmq.devices.monitoredqueue import monitored_queue
+
+
+class MonitoredQueueBase(ProxyBase):
+    """Base class for overriding methods."""
+    
+    _in_prefix = b''
+    _out_prefix = b''
+    
+    def __init__(self, in_type, out_type, mon_type=PUB, in_prefix=b'in', out_prefix=b'out'):
+        
+        ProxyBase.__init__(self, in_type=in_type, out_type=out_type, mon_type=mon_type)
+        
+        self._in_prefix = in_prefix
+        self._out_prefix = out_prefix
+
+    def run_device(self):
+        ins,outs,mons = self._setup_sockets()
+        monitored_queue(ins, outs, mons, self._in_prefix, self._out_prefix)
+
+
+class MonitoredQueue(MonitoredQueueBase, Proxy):
+    """Class for running monitored_queue in the background.
+
+    See zmq.devices.Device for most of the spec. MonitoredQueue differs from Proxy,
+    only in that it adds a ``prefix`` to messages sent on the monitor socket,
+    with a different prefix for each direction.
+    
+    MQ also supports ROUTER on both sides, which zmq.proxy does not.
+
+    If a message arrives on `in_sock`, it will be prefixed with `in_prefix` on the monitor socket.
+    If it arrives on out_sock, it will be prefixed with `out_prefix`.
+
+    A PUB socket is the most logical choice for the mon_socket, but it is not required.
+    """
+    pass
+
+
+class ThreadMonitoredQueue(MonitoredQueueBase, ThreadProxy):
+    """Run zmq.monitored_queue in a background thread.
+    
+    See MonitoredQueue and Proxy for details.
+    """
+    pass
+
+
+class ProcessMonitoredQueue(MonitoredQueueBase, ProcessProxy):
+    """Run zmq.monitored_queue in a background thread.
+    
+    See MonitoredQueue and Proxy for details.
+    """
+
+
+__all__ = [
+    'MonitoredQueue',
+    'ThreadMonitoredQueue',
+    'ProcessMonitoredQueue'
+]
diff --git a/zmq/devices/proxydevice.py b/zmq/devices/proxydevice.py
new file mode 100644
index 0000000..68be3f1
--- /dev/null
+++ b/zmq/devices/proxydevice.py
@@ -0,0 +1,90 @@
+"""Proxy classes and functions."""
+
+# Copyright (C) PyZMQ Developers
+# Distributed under the terms of the Modified BSD License.
+
+import zmq
+from zmq.devices.basedevice import Device, ThreadDevice, ProcessDevice
+
+
+class ProxyBase(object):
+    """Base class for overriding methods."""
+    
+    def __init__(self, in_type, out_type, mon_type=zmq.PUB):
+        
+        Device.__init__(self, in_type=in_type, out_type=out_type)
+        self.mon_type = mon_type
+        self._mon_binds = []
+        self._mon_connects = []
+        self._mon_sockopts = []
+
+    def bind_mon(self, addr):
+        """Enqueue ZMQ address for binding on mon_socket.
+
+        See zmq.Socket.bind for details.
+        """
+        self._mon_binds.append(addr)
+
+    def connect_mon(self, addr):
+        """Enqueue ZMQ address for connecting on mon_socket.
+
+        See zmq.Socket.bind for details.
+        """
+        self._mon_connects.append(addr)
+
+    def setsockopt_mon(self, opt, value):
+        """Enqueue setsockopt(opt, value) for mon_socket
+
+        See zmq.Socket.setsockopt for details.
+        """
+        self._mon_sockopts.append((opt, value))
+
+    def _setup_sockets(self):
+        ins,outs = Device._setup_sockets(self)
+        ctx = self._context
+        mons = ctx.socket(self.mon_type)
+        
+        # set sockopts (must be done first, in case of zmq.IDENTITY)
+        for opt,value in self._mon_sockopts:
+            mons.setsockopt(opt, value)
+        
+        for iface in self._mon_binds:
+            mons.bind(iface)
+        
+        for iface in self._mon_connects:
+            mons.connect(iface)
+        
+        return ins,outs,mons
+    
+    def run_device(self):
+        ins,outs,mons = self._setup_sockets()
+        zmq.proxy(ins, outs, mons)
+
+class Proxy(ProxyBase, Device):
+    """Threadsafe Proxy object.
+
+    See zmq.devices.Device for most of the spec. This subclass adds a
+    <method>_mon version of each <method>_{in|out} method, for configuring the
+    monitor socket.
+
+    A Proxy is a 3-socket ZMQ Device that functions just like a
+    QUEUE, except each message is also sent out on the monitor socket.
+
+    A PUB socket is the most logical choice for the mon_socket, but it is not required.
+    """
+    pass
+
+class ThreadProxy(ProxyBase, ThreadDevice):
+    """Proxy in a Thread. See Proxy for more."""
+    pass
+
+class ProcessProxy(ProxyBase, ProcessDevice):
+    """Proxy in a Process. See Proxy for more."""
+    pass
+
+
+__all__ = [
+    'Proxy',
+    'ThreadProxy',
+    'ProcessProxy',
+]
diff --git a/zmq/error.py b/zmq/error.py
new file mode 100644
index 0000000..48cdaaf
--- /dev/null
+++ b/zmq/error.py
@@ -0,0 +1,164 @@
+"""0MQ Error classes and functions."""
+
+# Copyright (C) PyZMQ Developers
+# Distributed under the terms of the Modified BSD License.
+
+
+class ZMQBaseError(Exception):
+    """Base exception class for 0MQ errors in Python."""
+    pass
+
+class ZMQError(ZMQBaseError):
+    """Wrap an errno style error.
+
+    Parameters
+    ----------
+    errno : int
+        The ZMQ errno or None.  If None, then ``zmq_errno()`` is called and
+        used.
+    msg : string
+        Description of the error or None.
+    """
+    errno = None
+
+    def __init__(self, errno=None, msg=None):
+        """Wrap an errno style error.
+
+        Parameters
+        ----------
+        errno : int
+            The ZMQ errno or None.  If None, then ``zmq_errno()`` is called and
+            used.
+        msg : string
+            Description of the error or None.
+        """
+        from zmq.backend import strerror, zmq_errno
+        if errno is None:
+            errno = zmq_errno()
+        if isinstance(errno, int):
+            self.errno = errno
+            if msg is None:
+                self.strerror = strerror(errno)
+            else:
+                self.strerror = msg
+        else:
+            if msg is None:
+                self.strerror = str(errno)
+            else:
+                self.strerror = msg
+        # flush signals, because there could be a SIGINT
+        # waiting to pounce, resulting in uncaught exceptions.
+        # Doing this here means getting SIGINT during a blocking
+        # libzmq call will raise a *catchable* KeyboardInterrupt
+        # PyErr_CheckSignals()
+
+    def __str__(self):
+        return self.strerror
+    
+    def __repr__(self):
+        return "ZMQError('%s')"%self.strerror
+
+
+class ZMQBindError(ZMQBaseError):
+    """An error for ``Socket.bind_to_random_port()``.
+    
+    See Also
+    --------
+    .Socket.bind_to_random_port
+    """
+    pass
+
+
+class NotDone(ZMQBaseError):
+    """Raised when timeout is reached while waiting for 0MQ to finish with a Message
+    
+    See Also
+    --------
+    .MessageTracker.wait : object for tracking when ZeroMQ is done
+    """
+    pass
+
+
+class ContextTerminated(ZMQError):
+    """Wrapper for zmq.ETERM
+    
+    .. versionadded:: 13.0
+    """
+    pass
+
+
+class Again(ZMQError):
+    """Wrapper for zmq.EAGAIN
+    
+    .. versionadded:: 13.0
+    """
+    pass
+
+
+def _check_rc(rc, errno=None):
+    """internal utility for checking zmq return condition
+    
+    and raising the appropriate Exception class
+    """
+    if rc < 0:
+        from zmq.backend import zmq_errno
+        if errno is None:
+            errno = zmq_errno()
+        from zmq import EAGAIN, ETERM
+        if errno == EAGAIN:
+            raise Again(errno)
+        elif errno == ETERM:
+            raise ContextTerminated(errno)
+        else:
+            raise ZMQError(errno)
+
+_zmq_version_info = None
+_zmq_version = None
+
+class ZMQVersionError(NotImplementedError):
+    """Raised when a feature is not provided by the linked version of libzmq.
+    
+    .. versionadded:: 14.2
+    """
+    min_version = None
+    def __init__(self, min_version, msg='Feature'):
+        global _zmq_version
+        if _zmq_version is None:
+            from zmq import zmq_version
+            _zmq_version = zmq_version()
+        self.msg = msg
+        self.min_version = min_version
+        self.version = _zmq_version
+    
+    def __repr__(self):
+        return "ZMQVersionError('%s')" % str(self)
+    
+    def __str__(self):
+        return "%s requires libzmq >= %s, have %s" % (self.msg, self.min_version, self.version)
+
+
+def _check_version(min_version_info, msg='Feature'):
+    """Check for libzmq
+    
+    raises ZMQVersionError if current zmq version is not at least min_version
+    
+    min_version_info is a tuple of integers, and will be compared against zmq.zmq_version_info().
+    """
+    global _zmq_version_info
+    if _zmq_version_info is None:
+        from zmq import zmq_version_info
+        _zmq_version_info = zmq_version_info()
+    if _zmq_version_info < min_version_info:
+        min_version = '.'.join(str(v) for v in min_version_info)
+        raise ZMQVersionError(min_version, msg)
+
+
+__all__ = [
+    'ZMQBaseError',
+    'ZMQBindError',
+    'ZMQError',
+    'NotDone',
+    'ContextTerminated',
+    'Again',
+    'ZMQVersionError',
+]
diff --git a/zmq/eventloop/__init__.py b/zmq/eventloop/__init__.py
new file mode 100644
index 0000000..568e8e8
--- /dev/null
+++ b/zmq/eventloop/__init__.py
@@ -0,0 +1,5 @@
+"""A Tornado based event loop for PyZMQ."""
+
+from zmq.eventloop.ioloop import IOLoop
+
+__all__ = ['IOLoop']
\ No newline at end of file
diff --git a/zmq/eventloop/ioloop.py b/zmq/eventloop/ioloop.py
new file mode 100644
index 0000000..35f4c41
--- /dev/null
+++ b/zmq/eventloop/ioloop.py
@@ -0,0 +1,193 @@
+# coding: utf-8
+"""tornado IOLoop API with zmq compatibility
+
+If you have tornado ≥ 3.0, this is a subclass of tornado's IOLoop,
+otherwise we ship a minimal subset of tornado in zmq.eventloop.minitornado.
+
+The minimal shipped version of tornado's IOLoop does not include
+support for concurrent futures - this will only be available if you
+have tornado ≥ 3.0.
+"""
+
+# Copyright (C) PyZMQ Developers
+# Distributed under the terms of the Modified BSD License.
+
+from __future__ import absolute_import, division, with_statement
+
+import os
+import time
+import warnings
+
+from zmq import (
+    Poller,
+    POLLIN, POLLOUT, POLLERR,
+    ZMQError, ETERM,
+)
+
+try:
+    import tornado
+    tornado_version = tornado.version_info
+except (ImportError, AttributeError):
+    tornado_version = ()
+
+try:
+    # tornado ≥ 3
+    from tornado.ioloop import PollIOLoop, PeriodicCallback
+    from tornado.log import gen_log
+except ImportError:
+    from .minitornado.ioloop import PollIOLoop, PeriodicCallback
+    from .minitornado.log import gen_log
+
+
+class DelayedCallback(PeriodicCallback):
+    """Schedules the given callback to be called once.
+
+    The callback is called once, after callback_time milliseconds.
+
+    `start` must be called after the DelayedCallback is created.
+    
+    The timeout is calculated from when `start` is called.
+    """
+    def __init__(self, callback, callback_time, io_loop=None):
+        # PeriodicCallback require callback_time to be positive
+        warnings.warn("""DelayedCallback is deprecated.
+        Use loop.add_timeout instead.""", DeprecationWarning)
+        callback_time = max(callback_time, 1e-3)
+        super(DelayedCallback, self).__init__(callback, callback_time, io_loop)
+    
+    def start(self):
+        """Starts the timer."""
+        self._running = True
+        self._firstrun = True
+        self._next_timeout = time.time() + self.callback_time / 1000.0
+        self.io_loop.add_timeout(self._next_timeout, self._run)
+    
+    def _run(self):
+        if not self._running: return
+        self._running = False
+        try:
+            self.callback()
+        except Exception:
+            gen_log.error("Error in delayed callback", exc_info=True)
+
+
+class ZMQPoller(object):
+    """A poller that can be used in the tornado IOLoop.
+    
+    This simply wraps a regular zmq.Poller, scaling the timeout
+    by 1000, so that it is in seconds rather than milliseconds.
+    """
+    
+    def __init__(self):
+        self._poller = Poller()
+    
+    @staticmethod
+    def _map_events(events):
+        """translate IOLoop.READ/WRITE/ERROR event masks into zmq.POLLIN/OUT/ERR"""
+        z_events = 0
+        if events & IOLoop.READ:
+            z_events |= POLLIN
+        if events & IOLoop.WRITE:
+            z_events |= POLLOUT
+        if events & IOLoop.ERROR:
+            z_events |= POLLERR
+        return z_events
+    
+    @staticmethod
+    def _remap_events(z_events):
+        """translate zmq.POLLIN/OUT/ERR event masks into IOLoop.READ/WRITE/ERROR"""
+        events = 0
+        if z_events & POLLIN:
+            events |= IOLoop.READ
+        if z_events & POLLOUT:
+            events |= IOLoop.WRITE
+        if z_events & POLLERR:
+            events |= IOLoop.ERROR
+        return events
+    
+    def register(self, fd, events):
+        return self._poller.register(fd, self._map_events(events))
+    
+    def modify(self, fd, events):
+        return self._poller.modify(fd, self._map_events(events))
+    
+    def unregister(self, fd):
+        return self._poller.unregister(fd)
+    
+    def poll(self, timeout):
+        """poll in seconds rather than milliseconds.
+        
+        Event masks will be IOLoop.READ/WRITE/ERROR
+        """
+        z_events = self._poller.poll(1000*timeout)
+        return [ (fd,self._remap_events(evt)) for (fd,evt) in z_events ]
+    
+    def close(self):
+        pass
+
+
+class ZMQIOLoop(PollIOLoop):
+    """ZMQ subclass of tornado's IOLoop"""
+    def initialize(self, impl=None, **kwargs):
+        impl = ZMQPoller() if impl is None else impl
+        super(ZMQIOLoop, self).initialize(impl=impl, **kwargs)
+    
+    @staticmethod
+    def instance():
+        """Returns a global `IOLoop` instance.
+        
+        Most applications have a single, global `IOLoop` running on the
+        main thread.  Use this method to get this instance from
+        another thread.  To get the current thread's `IOLoop`, use `current()`.
+        """
+        # install ZMQIOLoop as the active IOLoop implementation
+        # when using tornado 3
+        if tornado_version >= (3,):
+            PollIOLoop.configure(ZMQIOLoop)
+        return PollIOLoop.instance()
+    
+    def start(self):
+        try:
+            super(ZMQIOLoop, self).start()
+        except ZMQError as e:
+            if e.errno == ETERM:
+                # quietly return on ETERM
+                pass
+            else:
+                raise e
+
+
+if tornado_version >= (3,0) and tornado_version < (3,1):
+    def backport_close(self, all_fds=False):
+        """backport IOLoop.close to 3.0 from 3.1 (supports fd.close() method)"""
+        from zmq.eventloop.minitornado.ioloop import PollIOLoop as mini_loop
+        return mini_loop.close.__get__(self)(all_fds)
+    ZMQIOLoop.close = backport_close
+
+
+# public API name
+IOLoop = ZMQIOLoop
+
+
+def install():
+    """set the tornado IOLoop instance with the pyzmq IOLoop.
+    
+    After calling this function, tornado's IOLoop.instance() and pyzmq's
+    IOLoop.instance() will return the same object.
+    
+    An assertion error will be raised if tornado's IOLoop has been initialized
+    prior to calling this function.
+    """
+    from tornado import ioloop
+    # check if tornado's IOLoop is already initialized to something other
+    # than the pyzmq IOLoop instance:
+    assert (not ioloop.IOLoop.initialized()) or \
+        ioloop.IOLoop.instance() is IOLoop.instance(), "tornado IOLoop already initialized"
+    
+    if tornado_version >= (3,):
+        # tornado 3 has an official API for registering new defaults, yay!
+        ioloop.IOLoop.configure(ZMQIOLoop)
+    else:
+        # we have to set the global instance explicitly
+        ioloop.IOLoop._instance = IOLoop.instance()
+
diff --git a/zmq/eventloop/minitornado/__init__.py b/zmq/eventloop/minitornado/__init__.py
new file mode 100644
index 0000000..e69de29
--- /dev/null
+++ b/zmq/eventloop/minitornado/__init__.py
diff --git a/zmq/eventloop/minitornado/concurrent.py b/zmq/eventloop/minitornado/concurrent.py
new file mode 100644
index 0000000..519b23d
--- /dev/null
+++ b/zmq/eventloop/minitornado/concurrent.py
@@ -0,0 +1,11 @@
+"""pyzmq does not ship tornado's futures,
+this just raises informative NotImplementedErrors to avoid having to change too much code.
+"""
+
+class NotImplementedFuture(object):
+    def __init__(self, *args, **kwargs):
+        raise NotImplementedError("pyzmq does not ship tornado's Futures, "
+            "install tornado >= 3.0 for future support."
+        )
+
+Future = TracebackFuture = NotImplementedFuture
diff --git a/zmq/eventloop/minitornado/ioloop.py b/zmq/eventloop/minitornado/ioloop.py
new file mode 100644
index 0000000..710a3ec
--- /dev/null
+++ b/zmq/eventloop/minitornado/ioloop.py
@@ -0,0 +1,829 @@
+#!/usr/bin/env python
+#
+# Copyright 2009 Facebook
+#
+# Licensed under the Apache License, Version 2.0 (the "License"); you may
+# not use this file except in compliance with the License. You may obtain
+# a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+# License for the specific language governing permissions and limitations
+# under the License.
+
+"""An I/O event loop for non-blocking sockets.
+
+Typical applications will use a single `IOLoop` object, in the
+`IOLoop.instance` singleton.  The `IOLoop.start` method should usually
+be called at the end of the ``main()`` function.  Atypical applications may
+use more than one `IOLoop`, such as one `IOLoop` per thread, or per `unittest`
+case.
+
+In addition to I/O events, the `IOLoop` can also schedule time-based events.
+`IOLoop.add_timeout` is a non-blocking alternative to `time.sleep`.
+"""
+
+from __future__ import absolute_import, division, print_function, with_statement
+
+import datetime
+import errno
+import functools
+import heapq
+import logging
+import numbers
+import os
+import select
+import sys
+import threading
+import time
+import traceback
+
+from .concurrent import Future, TracebackFuture
+from .log import app_log, gen_log
+from . import stack_context
+from .util import Configurable
+
+try:
+    import signal
+except ImportError:
+    signal = None
+
+try:
+    import thread  # py2
+except ImportError:
+    import _thread as thread  # py3
+
+from .platform.auto import set_close_exec, Waker
+
+
+class TimeoutError(Exception):
+    pass
+
+
+class IOLoop(Configurable):
+    """A level-triggered I/O loop.
+
+    We use ``epoll`` (Linux) or ``kqueue`` (BSD and Mac OS X) if they
+    are available, or else we fall back on select(). If you are
+    implementing a system that needs to handle thousands of
+    simultaneous connections, you should use a system that supports
+    either ``epoll`` or ``kqueue``.
+
+    Example usage for a simple TCP server::
+
+        import errno
+        import functools
+        import ioloop
+        import socket
+
+        def connection_ready(sock, fd, events):
+            while True:
+                try:
+                    connection, address = sock.accept()
+                except socket.error, e:
+                    if e.args[0] not in (errno.EWOULDBLOCK, errno.EAGAIN):
+                        raise
+                    return
+                connection.setblocking(0)
+                handle_connection(connection, address)
+
+        sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM, 0)
+        sock.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
+        sock.setblocking(0)
+        sock.bind(("", port))
+        sock.listen(128)
+
+        io_loop = ioloop.IOLoop.instance()
+        callback = functools.partial(connection_ready, sock)
+        io_loop.add_handler(sock.fileno(), callback, io_loop.READ)
+        io_loop.start()
+
+    """
+    # Constants from the epoll module
+    _EPOLLIN = 0x001
+    _EPOLLPRI = 0x002
+    _EPOLLOUT = 0x004
+    _EPOLLERR = 0x008
+    _EPOLLHUP = 0x010
+    _EPOLLRDHUP = 0x2000
+    _EPOLLONESHOT = (1 << 30)
+    _EPOLLET = (1 << 31)
+
+    # Our events map exactly to the epoll events
+    NONE = 0
+    READ = _EPOLLIN
+    WRITE = _EPOLLOUT
+    ERROR = _EPOLLERR | _EPOLLHUP
+
+    # Global lock for creating global IOLoop instance
+    _instance_lock = threading.Lock()
+
+    _current = threading.local()
+
+    @staticmethod
+    def instance():
+        """Returns a global `IOLoop` instance.
+
+        Most applications have a single, global `IOLoop` running on the
+        main thread.  Use this method to get this instance from
+        another thread.  To get the current thread's `IOLoop`, use `current()`.
+        """
+        if not hasattr(IOLoop, "_instance"):
+            with IOLoop._instance_lock:
+                if not hasattr(IOLoop, "_instance"):
+                    # New instance after double check
+                    IOLoop._instance = IOLoop()
+        return IOLoop._instance
+
+    @staticmethod
+    def initialized():
+        """Returns true if the singleton instance has been created."""
+        return hasattr(IOLoop, "_instance")
+
+    def install(self):
+        """Installs this `IOLoop` object as the singleton instance.
+
+        This is normally not necessary as `instance()` will create
+        an `IOLoop` on demand, but you may want to call `install` to use
+        a custom subclass of `IOLoop`.
+        """
+        assert not IOLoop.initialized()
+        IOLoop._instance = self
+
+    @staticmethod
+    def current():
+        """Returns the current thread's `IOLoop`.
+
+        If an `IOLoop` is currently running or has been marked as current
+        by `make_current`, returns that instance.  Otherwise returns
+        `IOLoop.instance()`, i.e. the main thread's `IOLoop`.
+
+        A common pattern for classes that depend on ``IOLoops`` is to use
+        a default argument to enable programs with multiple ``IOLoops``
+        but not require the argument for simpler applications::
+
+            class MyClass(object):
+                def __init__(self, io_loop=None):
+                    self.io_loop = io_loop or IOLoop.current()
+
+        In general you should use `IOLoop.current` as the default when
+        constructing an asynchronous object, and use `IOLoop.instance`
+        when you mean to communicate to the main thread from a different
+        one.
+        """
+        current = getattr(IOLoop._current, "instance", None)
+        if current is None:
+            return IOLoop.instance()
+        return current
+
+    def make_current(self):
+        """Makes this the `IOLoop` for the current thread.
+
+        An `IOLoop` automatically becomes current for its thread
+        when it is started, but it is sometimes useful to call
+        `make_current` explictly before starting the `IOLoop`,
+        so that code run at startup time can find the right
+        instance.
+        """
+        IOLoop._current.instance = self
+
+    @staticmethod
+    def clear_current():
+        IOLoop._current.instance = None
+
+    @classmethod
+    def configurable_base(cls):
+        return IOLoop
+
+    @classmethod
+    def configurable_default(cls):
+        # this is the only patch to IOLoop:
+        from zmq.eventloop.ioloop import ZMQIOLoop
+        return ZMQIOLoop
+        # the remainder of this method is unused,
+        # but left for preservation reasons
+        if hasattr(select, "epoll"):
+            from tornado.platform.epoll import EPollIOLoop
+            return EPollIOLoop
+        if hasattr(select, "kqueue"):
+            # Python 2.6+ on BSD or Mac
+            from tornado.platform.kqueue import KQueueIOLoop
+            return KQueueIOLoop
+        from tornado.platform.select import SelectIOLoop
+        return SelectIOLoop
+
+    def initialize(self):
+        pass
+
+    def close(self, all_fds=False):
+        """Closes the `IOLoop`, freeing any resources used.
+
+        If ``all_fds`` is true, all file descriptors registered on the
+        IOLoop will be closed (not just the ones created by the
+        `IOLoop` itself).
+
+        Many applications will only use a single `IOLoop` that runs for the
+        entire lifetime of the process.  In that case closing the `IOLoop`
+        is not necessary since everything will be cleaned up when the
+        process exits.  `IOLoop.close` is provided mainly for scenarios
+        such as unit tests, which create and destroy a large number of
+        ``IOLoops``.
+
+        An `IOLoop` must be completely stopped before it can be closed.  This
+        means that `IOLoop.stop()` must be called *and* `IOLoop.start()` must
+        be allowed to return before attempting to call `IOLoop.close()`.
+        Therefore the call to `close` will usually appear just after
+        the call to `start` rather than near the call to `stop`.
+
+        .. versionchanged:: 3.1
+           If the `IOLoop` implementation supports non-integer objects
+           for "file descriptors", those objects will have their
+           ``close`` method when ``all_fds`` is true.
+        """
+        raise NotImplementedError()
+
+    def add_handler(self, fd, handler, events):
+        """Registers the given handler to receive the given events for fd.
+
+        The ``events`` argument is a bitwise or of the constants
+        ``IOLoop.READ``, ``IOLoop.WRITE``, and ``IOLoop.ERROR``.
+
+        When an event occurs, ``handler(fd, events)`` will be run.
+        """
+        raise NotImplementedError()
+
+    def update_handler(self, fd, events):
+        """Changes the events we listen for fd."""
+        raise NotImplementedError()
+
+    def remove_handler(self, fd):
+        """Stop listening for events on fd."""
+        raise NotImplementedError()
+
+    def set_blocking_signal_threshold(self, seconds, action):
+        """Sends a signal if the `IOLoop` is blocked for more than
+        ``s`` seconds.
+
+        Pass ``seconds=None`` to disable.  Requires Python 2.6 on a unixy
+        platform.
+
+        The action parameter is a Python signal handler.  Read the
+        documentation for the `signal` module for more information.
+        If ``action`` is None, the process will be killed if it is
+        blocked for too long.
+        """
+        raise NotImplementedError()
+
+    def set_blocking_log_threshold(self, seconds):
+        """Logs a stack trace if the `IOLoop` is blocked for more than
+        ``s`` seconds.
+
+        Equivalent to ``set_blocking_signal_threshold(seconds,
+        self.log_stack)``
+        """
+        self.set_blocking_signal_threshold(seconds, self.log_stack)
+
+    def log_stack(self, signal, frame):
+        """Signal handler to log the stack trace of the current thread.
+
+        For use with `set_blocking_signal_threshold`.
+        """
+        gen_log.warning('IOLoop blocked for %f seconds in\n%s',
+                        self._blocking_signal_threshold,
+                        ''.join(traceback.format_stack(frame)))
+
+    def start(self):
+        """Starts the I/O loop.
+
+        The loop will run until one of the callbacks calls `stop()`, which
+        will make the loop stop after the current event iteration completes.
+        """
+        raise NotImplementedError()
+
+    def stop(self):
+        """Stop the I/O loop.
+
+        If the event loop is not currently running, the next call to `start()`
+        will return immediately.
+
+        To use asynchronous methods from otherwise-synchronous code (such as
+        unit tests), you can start and stop the event loop like this::
+
+          ioloop = IOLoop()
+          async_method(ioloop=ioloop, callback=ioloop.stop)
+          ioloop.start()
+
+        ``ioloop.start()`` will return after ``async_method`` has run
+        its callback, whether that callback was invoked before or
+        after ``ioloop.start``.
+
+        Note that even after `stop` has been called, the `IOLoop` is not
+        completely stopped until `IOLoop.start` has also returned.
+        Some work that was scheduled before the call to `stop` may still
+        be run before the `IOLoop` shuts down.
+        """
+        raise NotImplementedError()
+
+    def run_sync(self, func, timeout=None):
+        """Starts the `IOLoop`, runs the given function, and stops the loop.
+
+        If the function returns a `.Future`, the `IOLoop` will run
+        until the future is resolved.  If it raises an exception, the
+        `IOLoop` will stop and the exception will be re-raised to the
+        caller.
+
+        The keyword-only argument ``timeout`` may be used to set
+        a maximum duration for the function.  If the timeout expires,
+        a `TimeoutError` is raised.
+
+        This method is useful in conjunction with `tornado.gen.coroutine`
+        to allow asynchronous calls in a ``main()`` function::
+
+            @gen.coroutine
+            def main():
+                # do stuff...
+
+            if __name__ == '__main__':
+                IOLoop.instance().run_sync(main)
+        """
+        future_cell = [None]
+
+        def run():
+            try:
+                result = func()
+            except Exception:
+                future_cell[0] = TracebackFuture()
+                future_cell[0].set_exc_info(sys.exc_info())
+            else:
+                if isinstance(result, Future):
+                    future_cell[0] = result
+                else:
+                    future_cell[0] = Future()
+                    future_cell[0].set_result(result)
+            self.add_future(future_cell[0], lambda future: self.stop())
+        self.add_callback(run)
+        if timeout is not None:
+            timeout_handle = self.add_timeout(self.time() + timeout, self.stop)
+        self.start()
+        if timeout is not None:
+            self.remove_timeout(timeout_handle)
+        if not future_cell[0].done():
+            raise TimeoutError('Operation timed out after %s seconds' % timeout)
+        return future_cell[0].result()
+
+    def time(self):
+        """Returns the current time according to the `IOLoop`'s clock.
+
+        The return value is a floating-point number relative to an
+        unspecified time in the past.
+
+        By default, the `IOLoop`'s time function is `time.time`.  However,
+        it may be configured to use e.g. `time.monotonic` instead.
+        Calls to `add_timeout` that pass a number instead of a
+        `datetime.timedelta` should use this function to compute the
+        appropriate time, so they can work no matter what time function
+        is chosen.
+        """
+        return time.time()
+
+    def add_timeout(self, deadline, callback):
+        """Runs the ``callback`` at the time ``deadline`` from the I/O loop.
+
+        Returns an opaque handle that may be passed to
+        `remove_timeout` to cancel.
+
+        ``deadline`` may be a number denoting a time (on the same
+        scale as `IOLoop.time`, normally `time.time`), or a
+        `datetime.timedelta` object for a deadline relative to the
+        current time.
+
+        Note that it is not safe to call `add_timeout` from other threads.
+        Instead, you must use `add_callback` to transfer control to the
+        `IOLoop`'s thread, and then call `add_timeout` from there.
+        """
+        raise NotImplementedError()
+
+    def remove_timeout(self, timeout):
+        """Cancels a pending timeout.
+
+        The argument is a handle as returned by `add_timeout`.  It is
+        safe to call `remove_timeout` even if the callback has already
+        been run.
+        """
+        raise NotImplementedError()
+
+    def add_callback(self, callback, *args, **kwargs):
+        """Calls the given callback on the next I/O loop iteration.
+
+        It is safe to call this method from any thread at any time,
+        except from a signal handler.  Note that this is the **only**
+        method in `IOLoop` that makes this thread-safety guarantee; all
+        other interaction with the `IOLoop` must be done from that
+        `IOLoop`'s thread.  `add_callback()` may be used to transfer
+        control from other threads to the `IOLoop`'s thread.
+
+        To add a callback from a signal handler, see
+        `add_callback_from_signal`.
+        """
+        raise NotImplementedError()
+
+    def add_callback_from_signal(self, callback, *args, **kwargs):
+        """Calls the given callback on the next I/O loop iteration.
+
+        Safe for use from a Python signal handler; should not be used
+        otherwise.
+
+        Callbacks added with this method will be run without any
+        `.stack_context`, to avoid picking up the context of the function
+        that was interrupted by the signal.
+        """
+        raise NotImplementedError()
+
+    def add_future(self, future, callback):
+        """Schedules a callback on the ``IOLoop`` when the given
+        `.Future` is finished.
+
+        The callback is invoked with one argument, the
+        `.Future`.
+        """
+        assert isinstance(future, Future)
+        callback = stack_context.wrap(callback)
+        future.add_done_callback(
+            lambda future: self.add_callback(callback, future))
+
+    def _run_callback(self, callback):
+        """Runs a callback with error handling.
+
+        For use in subclasses.
+        """
+        try:
+            callback()
+        except Exception:
+            self.handle_callback_exception(callback)
+
+    def handle_callback_exception(self, callback):
+        """This method is called whenever a callback run by the `IOLoop`
+        throws an exception.
+
+        By default simply logs the exception as an error.  Subclasses
+        may override this method to customize reporting of exceptions.
+
+        The exception itself is not passed explicitly, but is available
+        in `sys.exc_info`.
+        """
+        app_log.error("Exception in callback %r", callback, exc_info=True)
+
+
+class PollIOLoop(IOLoop):
+    """Base class for IOLoops built around a select-like function.
+
+    For concrete implementations, see `tornado.platform.epoll.EPollIOLoop`
+    (Linux), `tornado.platform.kqueue.KQueueIOLoop` (BSD and Mac), or
+    `tornado.platform.select.SelectIOLoop` (all platforms).
+    """
+    def initialize(self, impl, time_func=None):
+        super(PollIOLoop, self).initialize()
+        self._impl = impl
+        if hasattr(self._impl, 'fileno'):
+            set_close_exec(self._impl.fileno())
+        self.time_func = time_func or time.time
+        self._handlers = {}
+        self._events = {}
+        self._callbacks = []
+        self._callback_lock = threading.Lock()
+        self._timeouts = []
+        self._cancellations = 0
+        self._running = False
+        self._stopped = False
+        self._closing = False
+        self._thread_ident = None
+        self._blocking_signal_threshold = None
+
+        # Create a pipe that we send bogus data to when we want to wake
+        # the I/O loop when it is idle
+        self._waker = Waker()
+        self.add_handler(self._waker.fileno(),
+                         lambda fd, events: self._waker.consume(),
+                         self.READ)
+
+    def close(self, all_fds=False):
+        with self._callback_lock:
+            self._closing = True
+        self.remove_handler(self._waker.fileno())
+        if all_fds:
+            for fd in self._handlers.keys():
+                try:
+                    close_method = getattr(fd, 'close', None)
+                    if close_method is not None:
+                        close_method()
+                    else:
+                        os.close(fd)
+                except Exception:
+                    gen_log.debug("error closing fd %s", fd, exc_info=True)
+        self._waker.close()
+        self._impl.close()
+
+    def add_handler(self, fd, handler, events):
+        self._handlers[fd] = stack_context.wrap(handler)
+        self._impl.register(fd, events | self.ERROR)
+
+    def update_handler(self, fd, events):
+        self._impl.modify(fd, events | self.ERROR)
+
+    def remove_handler(self, fd):
+        self._handlers.pop(fd, None)
+        self._events.pop(fd, None)
+        try:
+            self._impl.unregister(fd)
+        except Exception:
+            gen_log.debug("Error deleting fd from IOLoop", exc_info=True)
+
+    def set_blocking_signal_threshold(self, seconds, action):
+        if not hasattr(signal, "setitimer"):
+            gen_log.error("set_blocking_signal_threshold requires a signal module "
+                          "with the setitimer method")
+            return
+        self._blocking_signal_threshold = seconds
+        if seconds is not None:
+            signal.signal(signal.SIGALRM,
+                          action if action is not None else signal.SIG_DFL)
+
+    def start(self):
+        if not logging.getLogger().handlers:
+            # The IOLoop catches and logs exceptions, so it's
+            # important that log output be visible.  However, python's
+            # default behavior for non-root loggers (prior to python
+            # 3.2) is to print an unhelpful "no handlers could be
+            # found" message rather than the actual log entry, so we
+            # must explicitly configure logging if we've made it this
+            # far without anything.
+            logging.basicConfig()
+        if self._stopped:
+            self._stopped = False
+            return
+        old_current = getattr(IOLoop._current, "instance", None)
+        IOLoop._current.instance = self
+        self._thread_ident = thread.get_ident()
+        self._running = True
+
+        # signal.set_wakeup_fd closes a race condition in event loops:
+        # a signal may arrive at the beginning of select/poll/etc
+        # before it goes into its interruptible sleep, so the signal
+        # will be consumed without waking the select.  The solution is
+        # for the (C, synchronous) signal handler to write to a pipe,
+        # which will then be seen by select.
+        #
+        # In python's signal handling semantics, this only matters on the
+        # main thread (fortunately, set_wakeup_fd only works on the main
+        # thread and will raise a ValueError otherwise).
+        #
+        # If someone has already set a wakeup fd, we don't want to
+        # disturb it.  This is an issue for twisted, which does its
+        # SIGCHILD processing in response to its own wakeup fd being
+        # written to.  As long as the wakeup fd is registered on the IOLoop,
+        # the loop will still wake up and everything should work.
+        old_wakeup_fd = None
+        if hasattr(signal, 'set_wakeup_fd') and os.name == 'posix':
+            # requires python 2.6+, unix.  set_wakeup_fd exists but crashes
+            # the python process on windows.
+            try:
+                old_wakeup_fd = signal.set_wakeup_fd(self._waker.write_fileno())
+                if old_wakeup_fd != -1:
+                    # Already set, restore previous value.  This is a little racy,
+                    # but there's no clean get_wakeup_fd and in real use the
+                    # IOLoop is just started once at the beginning.
+                    signal.set_wakeup_fd(old_wakeup_fd)
+                    old_wakeup_fd = None
+            except ValueError:  # non-main thread
+                pass
+
+        while True:
+            poll_timeout = 3600.0
+
+            # Prevent IO event starvation by delaying new callbacks
+            # to the next iteration of the event loop.
+            with self._callback_lock:
+                callbacks = self._callbacks
+                self._callbacks = []
+            for callback in callbacks:
+                self._run_callback(callback)
+
+            if self._timeouts:
+                now = self.time()
+                while self._timeouts:
+                    if self._timeouts[0].callback is None:
+                        # the timeout was cancelled
+                        heapq.heappop(self._timeouts)
+                        self._cancellations -= 1
+                    elif self._timeouts[0].deadline <= now:
+                        timeout = heapq.heappop(self._timeouts)
+                        self._run_callback(timeout.callback)
+                    else:
+                        seconds = self._timeouts[0].deadline - now
+                        poll_timeout = min(seconds, poll_timeout)
+                        break
+                if (self._cancellations > 512
+                        and self._cancellations > (len(self._timeouts) >> 1)):
+                    # Clean up the timeout queue when it gets large and it's
+                    # more than half cancellations.
+                    self._cancellations = 0
+                    self._timeouts = [x for x in self._timeouts
+                                      if x.callback is not None]
+                    heapq.heapify(self._timeouts)
+
+            if self._callbacks:
+                # If any callbacks or timeouts called add_callback,
+                # we don't want to wait in poll() before we run them.
+                poll_timeout = 0.0
+
+            if not self._running:
+                break
+
+            if self._blocking_signal_threshold is not None:
+                # clear alarm so it doesn't fire while poll is waiting for
+                # events.
+                signal.setitimer(signal.ITIMER_REAL, 0, 0)
+
+            try:
+                event_pairs = self._impl.poll(poll_timeout)
+            except Exception as e:
+                # Depending on python version and IOLoop implementation,
+                # different exception types may be thrown and there are
+                # two ways EINTR might be signaled:
+                # * e.errno == errno.EINTR
+                # * e.args is like (errno.EINTR, 'Interrupted system call')
+                if (getattr(e, 'errno', None) == errno.EINTR or
+                    (isinstance(getattr(e, 'args', None), tuple) and
+                     len(e.args) == 2 and e.args[0] == errno.EINTR)):
+                    continue
+                else:
+                    raise
+
+            if self._blocking_signal_threshold is not None:
+                signal.setitimer(signal.ITIMER_REAL,
+                                 self._blocking_signal_threshold, 0)
+
+            # Pop one fd at a time from the set of pending fds and run
+            # its handler. Since that handler may perform actions on
+            # other file descriptors, there may be reentrant calls to
+            # this IOLoop that update self._events
+            self._events.update(event_pairs)
+            while self._events:
+                fd, events = self._events.popitem()
+                try:
+                    self._handlers[fd](fd, events)
+                except (OSError, IOError) as e:
+                    if e.args[0] == errno.EPIPE:
+                        # Happens when the client closes the connection
+                        pass
+                    else:
+                        app_log.error("Exception in I/O handler for fd %s",
+                                      fd, exc_info=True)
+                except Exception:
+                    app_log.error("Exception in I/O handler for fd %s",
+                                  fd, exc_info=True)
+        # reset the stopped flag so another start/stop pair can be issued
+        self._stopped = False
+        if self._blocking_signal_threshold is not None:
+            signal.setitimer(signal.ITIMER_REAL, 0, 0)
+        IOLoop._current.instance = old_current
+        if old_wakeup_fd is not None:
+            signal.set_wakeup_fd(old_wakeup_fd)
+
+    def stop(self):
+        self._running = False
+        self._stopped = True
+        self._waker.wake()
+
+    def time(self):
+        return self.time_func()
+
+    def add_timeout(self, deadline, callback):
+        timeout = _Timeout(deadline, stack_context.wrap(callback), self)
+        heapq.heappush(self._timeouts, timeout)
+        return timeout
+
+    def remove_timeout(self, timeout):
+        # Removing from a heap is complicated, so just leave the defunct
+        # timeout object in the queue (see discussion in
+        # http://docs.python.org/library/heapq.html).
+        # If this turns out to be a problem, we could add a garbage
+        # collection pass whenever there are too many dead timeouts.
+        timeout.callback = None
+        self._cancellations += 1
+
+    def add_callback(self, callback, *args, **kwargs):
+        with self._callback_lock:
+            if self._closing:
+                raise RuntimeError("IOLoop is closing")
+            list_empty = not self._callbacks
+            self._callbacks.append(functools.partial(
+                stack_context.wrap(callback), *args, **kwargs))
+        if list_empty and thread.get_ident() != self._thread_ident:
+            # If we're in the IOLoop's thread, we know it's not currently
+            # polling.  If we're not, and we added the first callback to an
+            # empty list, we may need to wake it up (it may wake up on its
+            # own, but an occasional extra wake is harmless).  Waking
+            # up a polling IOLoop is relatively expensive, so we try to
+            # avoid it when we can.
+            self._waker.wake()
+
+    def add_callback_from_signal(self, callback, *args, **kwargs):
+        with stack_context.NullContext():
+            if thread.get_ident() != self._thread_ident:
+                # if the signal is handled on another thread, we can add
+                # it normally (modulo the NullContext)
+                self.add_callback(callback, *args, **kwargs)
+            else:
+                # If we're on the IOLoop's thread, we cannot use
+                # the regular add_callback because it may deadlock on
+                # _callback_lock.  Blindly insert into self._callbacks.
+                # This is safe because the GIL makes list.append atomic.
+                # One subtlety is that if the signal interrupted the
+                # _callback_lock block in IOLoop.start, we may modify
+                # either the old or new version of self._callbacks,
+                # but either way will work.
+                self._callbacks.append(functools.partial(
+                    stack_context.wrap(callback), *args, **kwargs))
+
+
+class _Timeout(object):
+    """An IOLoop timeout, a UNIX timestamp and a callback"""
+
+    # Reduce memory overhead when there are lots of pending callbacks
+    __slots__ = ['deadline', 'callback']
+
+    def __init__(self, deadline, callback, io_loop):
+        if isinstance(deadline, numbers.Real):
+            self.deadline = deadline
+        elif isinstance(deadline, datetime.timedelta):
+            self.deadline = io_loop.time() + _Timeout.timedelta_to_seconds(deadline)
+        else:
+            raise TypeError("Unsupported deadline %r" % deadline)
+        self.callback = callback
+
+    @staticmethod
+    def timedelta_to_seconds(td):
+        """Equivalent to td.total_seconds() (introduced in python 2.7)."""
+        return (td.microseconds + (td.seconds + td.days * 24 * 3600) * 10 ** 6) / float(10 ** 6)
+
+    # Comparison methods to sort by deadline, with object id as a tiebreaker
+    # to guarantee a consistent ordering.  The heapq module uses __le__
+    # in python2.5, and __lt__ in 2.6+ (sort() and most other comparisons
+    # use __lt__).
+    def __lt__(self, other):
+        return ((self.deadline, id(self)) <
+                (other.deadline, id(other)))
+
+    def __le__(self, other):
+        return ((self.deadline, id(self)) <=
+                (other.deadline, id(other)))
+
+
+class PeriodicCallback(object):
+    """Schedules the given callback to be called periodically.
+
+    The callback is called every ``callback_time`` milliseconds.
+
+    `start` must be called after the `PeriodicCallback` is created.
+    """
+    def __init__(self, callback, callback_time, io_loop=None):
+        self.callback = callback
+        if callback_time <= 0:
+            raise ValueError("Periodic callback must have a positive callback_time")
+        self.callback_time = callback_time
+        self.io_loop = io_loop or IOLoop.current()
+        self._running = False
+        self._timeout = None
+
+    def start(self):
+        """Starts the timer."""
+        self._running = True
+        self._next_timeout = self.io_loop.time()
+        self._schedule_next()
+
+    def stop(self):
+        """Stops the timer."""
+        self._running = False
+        if self._timeout is not None:
+            self.io_loop.remove_timeout(self._timeout)
+            self._timeout = None
+
+    def _run(self):
+        if not self._running:
+            return
+        try:
+            self.callback()
+        except Exception:
+            app_log.error("Error in periodic callback", exc_info=True)
+        self._schedule_next()
+
+    def _schedule_next(self):
+        if self._running:
+            current_time = self.io_loop.time()
+            while self._next_timeout <= current_time:
+                self._next_timeout += self.callback_time / 1000.0
+            self._timeout = self.io_loop.add_timeout(self._next_timeout, self._run)
diff --git a/zmq/eventloop/minitornado/log.py b/zmq/eventloop/minitornado/log.py
new file mode 100644
index 0000000..49051e8
--- /dev/null
+++ b/zmq/eventloop/minitornado/log.py
@@ -0,0 +1,6 @@
+"""minimal subset of tornado.log for zmq.eventloop.minitornado"""
+
+import logging
+
+app_log = logging.getLogger("tornado.application")
+gen_log = logging.getLogger("tornado.general")
diff --git a/zmq/eventloop/minitornado/platform/__init__.py b/zmq/eventloop/minitornado/platform/__init__.py
new file mode 100644
index 0000000..e69de29
--- /dev/null
+++ b/zmq/eventloop/minitornado/platform/__init__.py
diff --git a/zmq/eventloop/minitornado/platform/auto.py b/zmq/eventloop/minitornado/platform/auto.py
new file mode 100644
index 0000000..b40ccd9
--- /dev/null
+++ b/zmq/eventloop/minitornado/platform/auto.py
@@ -0,0 +1,45 @@
+#!/usr/bin/env python
+#
+# Copyright 2011 Facebook
+#
+# Licensed under the Apache License, Version 2.0 (the "License"); you may
+# not use this file except in compliance with the License. You may obtain
+# a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+# License for the specific language governing permissions and limitations
+# under the License.
+
+"""Implementation of platform-specific functionality.
+
+For each function or class described in `tornado.platform.interface`,
+the appropriate platform-specific implementation exists in this module.
+Most code that needs access to this functionality should do e.g.::
+
+    from tornado.platform.auto import set_close_exec
+"""
+
+from __future__ import absolute_import, division, print_function, with_statement
+
+import os
+
+if os.name == 'nt':
+    from .common import Waker
+    from .windows import set_close_exec
+else:
+    from .posix import set_close_exec, Waker
+
+try:
+    # monotime monkey-patches the time module to have a monotonic function
+    # in versions of python before 3.3.
+    import monotime
+except ImportError:
+    pass
+try:
+    from time import monotonic as monotonic_time
+except ImportError:
+    monotonic_time = None
diff --git a/zmq/eventloop/minitornado/platform/common.py b/zmq/eventloop/minitornado/platform/common.py
new file mode 100644
index 0000000..2d75dc1
--- /dev/null
+++ b/zmq/eventloop/minitornado/platform/common.py
@@ -0,0 +1,91 @@
+"""Lowest-common-denominator implementations of platform functionality."""
+from __future__ import absolute_import, division, print_function, with_statement
+
+import errno
+import socket
+
+from . import interface
+
+
+class Waker(interface.Waker):
+    """Create an OS independent asynchronous pipe.
+
+    For use on platforms that don't have os.pipe() (or where pipes cannot
+    be passed to select()), but do have sockets.  This includes Windows
+    and Jython.
+    """
+    def __init__(self):
+        # Based on Zope async.py: http://svn.zope.org/zc.ngi/trunk/src/zc/ngi/async.py
+
+        self.writer = socket.socket()
+        # Disable buffering -- pulling the trigger sends 1 byte,
+        # and we want that sent immediately, to wake up ASAP.
+        self.writer.setsockopt(socket.IPPROTO_TCP, socket.TCP_NODELAY, 1)
+
+        count = 0
+        while 1:
+            count += 1
+            # Bind to a local port; for efficiency, let the OS pick
+            # a free port for us.
+            # Unfortunately, stress tests showed that we may not
+            # be able to connect to that port ("Address already in
+            # use") despite that the OS picked it.  This appears
+            # to be a race bug in the Windows socket implementation.
+            # So we loop until a connect() succeeds (almost always
+            # on the first try).  See the long thread at
+            # http://mail.zope.org/pipermail/zope/2005-July/160433.html
+            # for hideous details.
+            a = socket.socket()
+            a.bind(("127.0.0.1", 0))
+            a.listen(1)
+            connect_address = a.getsockname()  # assigned (host, port) pair
+            try:
+                self.writer.connect(connect_address)
+                break    # success
+            except socket.error as detail:
+                if (not hasattr(errno, 'WSAEADDRINUSE') or
+                        detail[0] != errno.WSAEADDRINUSE):
+                    # "Address already in use" is the only error
+                    # I've seen on two WinXP Pro SP2 boxes, under
+                    # Pythons 2.3.5 and 2.4.1.
+                    raise
+                # (10048, 'Address already in use')
+                # assert count <= 2 # never triggered in Tim's tests
+                if count >= 10:  # I've never seen it go above 2
+                    a.close()
+                    self.writer.close()
+                    raise socket.error("Cannot bind trigger!")
+                # Close `a` and try again.  Note:  I originally put a short
+                # sleep() here, but it didn't appear to help or hurt.
+                a.close()
+
+        self.reader, addr = a.accept()
+        self.reader.setblocking(0)
+        self.writer.setblocking(0)
+        a.close()
+        self.reader_fd = self.reader.fileno()
+
+    def fileno(self):
+        return self.reader.fileno()
+
+    def write_fileno(self):
+        return self.writer.fileno()
+
+    def wake(self):
+        try:
+            self.writer.send(b"x")
+        except (IOError, socket.error):
+            pass
+
+    def consume(self):
+        try:
+            while True:
+                result = self.reader.recv(1024)
+                if not result:
+                    break
+        except (IOError, socket.error):
+            pass
+
+    def close(self):
+        self.reader.close()
+        self.writer.close()
diff --git a/zmq/eventloop/minitornado/platform/interface.py b/zmq/eventloop/minitornado/platform/interface.py
new file mode 100644
index 0000000..07da6ba
--- /dev/null
+++ b/zmq/eventloop/minitornado/platform/interface.py
@@ -0,0 +1,63 @@
+#!/usr/bin/env python
+#
+# Copyright 2011 Facebook
+#
+# Licensed under the Apache License, Version 2.0 (the "License"); you may
+# not use this file except in compliance with the License. You may obtain
+# a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+# License for the specific language governing permissions and limitations
+# under the License.
+
+"""Interfaces for platform-specific functionality.
+
+This module exists primarily for documentation purposes and as base classes
+for other tornado.platform modules.  Most code should import the appropriate
+implementation from `tornado.platform.auto`.
+"""
+
+from __future__ import absolute_import, division, print_function, with_statement
+
+
+def set_close_exec(fd):
+    """Sets the close-on-exec bit (``FD_CLOEXEC``)for a file descriptor."""
+    raise NotImplementedError()
+
+
+class Waker(object):
+    """A socket-like object that can wake another thread from ``select()``.
+
+    The `~tornado.ioloop.IOLoop` will add the Waker's `fileno()` to
+    its ``select`` (or ``epoll`` or ``kqueue``) calls.  When another
+    thread wants to wake up the loop, it calls `wake`.  Once it has woken
+    up, it will call `consume` to do any necessary per-wake cleanup.  When
+    the ``IOLoop`` is closed, it closes its waker too.
+    """
+    def fileno(self):
+        """Returns the read file descriptor for this waker.
+
+        Must be suitable for use with ``select()`` or equivalent on the
+        local platform.
+        """
+        raise NotImplementedError()
+
+    def write_fileno(self):
+        """Returns the write file descriptor for this waker."""
+        raise NotImplementedError()
+
+    def wake(self):
+        """Triggers activity on the waker's file descriptor."""
+        raise NotImplementedError()
+
+    def consume(self):
+        """Called after the listen has woken up to do any necessary cleanup."""
+        raise NotImplementedError()
+
+    def close(self):
+        """Closes the waker's file descriptor(s)."""
+        raise NotImplementedError()
diff --git a/zmq/eventloop/minitornado/platform/posix.py b/zmq/eventloop/minitornado/platform/posix.py
new file mode 100644
index 0000000..ccffbb6
--- /dev/null
+++ b/zmq/eventloop/minitornado/platform/posix.py
@@ -0,0 +1,70 @@
+#!/usr/bin/env python
+#
+# Copyright 2011 Facebook
+#
+# Licensed under the Apache License, Version 2.0 (the "License"); you may
+# not use this file except in compliance with the License. You may obtain
+# a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+# License for the specific language governing permissions and limitations
+# under the License.
+
+"""Posix implementations of platform-specific functionality."""
+
+from __future__ import absolute_import, division, print_function, with_statement
+
+import fcntl
+import os
+
+from . import interface
+
+
+def set_close_exec(fd):
+    flags = fcntl.fcntl(fd, fcntl.F_GETFD)
+    fcntl.fcntl(fd, fcntl.F_SETFD, flags | fcntl.FD_CLOEXEC)
+
+
+def _set_nonblocking(fd):
+    flags = fcntl.fcntl(fd, fcntl.F_GETFL)
+    fcntl.fcntl(fd, fcntl.F_SETFL, flags | os.O_NONBLOCK)
+
+
+class Waker(interface.Waker):
+    def __init__(self):
+        r, w = os.pipe()
+        _set_nonblocking(r)
+        _set_nonblocking(w)
+        set_close_exec(r)
+        set_close_exec(w)
+        self.reader = os.fdopen(r, "rb", 0)
+        self.writer = os.fdopen(w, "wb", 0)
+
+    def fileno(self):
+        return self.reader.fileno()
+
+    def write_fileno(self):
+        return self.writer.fileno()
+
+    def wake(self):
+        try:
+            self.writer.write(b"x")
+        except IOError:
+            pass
+
+    def consume(self):
+        try:
+            while True:
+                result = self.reader.read()
+                if not result:
+                    break
+        except IOError:
+            pass
+
+    def close(self):
+        self.reader.close()
+        self.writer.close()
diff --git a/zmq/eventloop/minitornado/platform/windows.py b/zmq/eventloop/minitornado/platform/windows.py
new file mode 100644
index 0000000..817bdca
--- /dev/null
+++ b/zmq/eventloop/minitornado/platform/windows.py
@@ -0,0 +1,20 @@
+# NOTE: win32 support is currently experimental, and not recommended
+# for production use.
+
+
+from __future__ import absolute_import, division, print_function, with_statement
+import ctypes
+import ctypes.wintypes
+
+# See: http://msdn.microsoft.com/en-us/library/ms724935(VS.85).aspx
+SetHandleInformation = ctypes.windll.kernel32.SetHandleInformation
+SetHandleInformation.argtypes = (ctypes.wintypes.HANDLE, ctypes.wintypes.DWORD, ctypes.wintypes.DWORD)
+SetHandleInformation.restype = ctypes.wintypes.BOOL
+
+HANDLE_FLAG_INHERIT = 0x00000001
+
+
+def set_close_exec(fd):
+    success = SetHandleInformation(fd, HANDLE_FLAG_INHERIT, 0)
+    if not success:
+        raise ctypes.GetLastError()
diff --git a/zmq/eventloop/minitornado/stack_context.py b/zmq/eventloop/minitornado/stack_context.py
new file mode 100644
index 0000000..226d804
--- /dev/null
+++ b/zmq/eventloop/minitornado/stack_context.py
@@ -0,0 +1,376 @@
+#!/usr/bin/env python
+#
+# Copyright 2010 Facebook
+#
+# Licensed under the Apache License, Version 2.0 (the "License"); you may
+# not use this file except in compliance with the License. You may obtain
+# a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+# License for the specific language governing permissions and limitations
+# under the License.
+
+"""`StackContext` allows applications to maintain threadlocal-like state
+that follows execution as it moves to other execution contexts.
+
+The motivating examples are to eliminate the need for explicit
+``async_callback`` wrappers (as in `tornado.web.RequestHandler`), and to
+allow some additional context to be kept for logging.
+
+This is slightly magic, but it's an extension of the idea that an
+exception handler is a kind of stack-local state and when that stack
+is suspended and resumed in a new context that state needs to be
+preserved.  `StackContext` shifts the burden of restoring that state
+from each call site (e.g.  wrapping each `.AsyncHTTPClient` callback
+in ``async_callback``) to the mechanisms that transfer control from
+one context to another (e.g. `.AsyncHTTPClient` itself, `.IOLoop`,
+thread pools, etc).
+
+Example usage::
+
+    @contextlib.contextmanager
+    def die_on_error():
+        try:
+            yield
+        except Exception:
+            logging.error("exception in asynchronous operation",exc_info=True)
+            sys.exit(1)
+
+    with StackContext(die_on_error):
+        # Any exception thrown here *or in callback and its desendents*
+        # will cause the process to exit instead of spinning endlessly
+        # in the ioloop.
+        http_client.fetch(url, callback)
+    ioloop.start()
+
+Most applications shouln't have to work with `StackContext` directly.
+Here are a few rules of thumb for when it's necessary:
+
+* If you're writing an asynchronous library that doesn't rely on a
+  stack_context-aware library like `tornado.ioloop` or `tornado.iostream`
+  (for example, if you're writing a thread pool), use
+  `.stack_context.wrap()` before any asynchronous operations to capture the
+  stack context from where the operation was started.
+
+* If you're writing an asynchronous library that has some shared
+  resources (such as a connection pool), create those shared resources
+  within a ``with stack_context.NullContext():`` block.  This will prevent
+  ``StackContexts`` from leaking from one request to another.
+
+* If you want to write something like an exception handler that will
+  persist across asynchronous calls, create a new `StackContext` (or
+  `ExceptionStackContext`), and make your asynchronous calls in a ``with``
+  block that references your `StackContext`.
+"""
+
+from __future__ import absolute_import, division, print_function, with_statement
+
+import sys
+import threading
+
+from .util import raise_exc_info
+
+
+class StackContextInconsistentError(Exception):
+    pass
+
+
+class _State(threading.local):
+    def __init__(self):
+        self.contexts = (tuple(), None)
+_state = _State()
+
+
+class StackContext(object):
+    """Establishes the given context as a StackContext that will be transferred.
+
+    Note that the parameter is a callable that returns a context
+    manager, not the context itself.  That is, where for a
+    non-transferable context manager you would say::
+
+      with my_context():
+
+    StackContext takes the function itself rather than its result::
+
+      with StackContext(my_context):
+
+    The result of ``with StackContext() as cb:`` is a deactivation
+    callback.  Run this callback when the StackContext is no longer
+    needed to ensure that it is not propagated any further (note that
+    deactivating a context does not affect any instances of that
+    context that are currently pending).  This is an advanced feature
+    and not necessary in most applications.
+    """
+    def __init__(self, context_factory):
+        self.context_factory = context_factory
+        self.contexts = []
+        self.active = True
+
+    def _deactivate(self):
+        self.active = False
+
+    # StackContext protocol
+    def enter(self):
+        context = self.context_factory()
+        self.contexts.append(context)
+        context.__enter__()
+
+    def exit(self, type, value, traceback):
+        context = self.contexts.pop()
+        context.__exit__(type, value, traceback)
+
+    # Note that some of this code is duplicated in ExceptionStackContext
+    # below.  ExceptionStackContext is more common and doesn't need
+    # the full generality of this class.
+    def __enter__(self):
+        self.old_contexts = _state.contexts
+        self.new_contexts = (self.old_contexts[0] + (self,), self)
+        _state.contexts = self.new_contexts
+
+        try:
+            self.enter()
+        except:
+            _state.contexts = self.old_contexts
+            raise
+
+        return self._deactivate
+
+    def __exit__(self, type, value, traceback):
+        try:
+            self.exit(type, value, traceback)
+        finally:
+            final_contexts = _state.contexts
+            _state.contexts = self.old_contexts
+
+            # Generator coroutines and with-statements with non-local
+            # effects interact badly.  Check here for signs of
+            # the stack getting out of sync.
+            # Note that this check comes after restoring _state.context
+            # so that if it fails things are left in a (relatively)
+            # consistent state.
+            if final_contexts is not self.new_contexts:
+                raise StackContextInconsistentError(
+                    'stack_context inconsistency (may be caused by yield '
+                    'within a "with StackContext" block)')
+
+            # Break up a reference to itself to allow for faster GC on CPython.
+            self.new_contexts = None
+
+
+class ExceptionStackContext(object):
+    """Specialization of StackContext for exception handling.
+
+    The supplied ``exception_handler`` function will be called in the
+    event of an uncaught exception in this context.  The semantics are
+    similar to a try/finally clause, and intended use cases are to log
+    an error, close a socket, or similar cleanup actions.  The
+    ``exc_info`` triple ``(type, value, traceback)`` will be passed to the
+    exception_handler function.
+
+    If the exception handler returns true, the exception will be
+    consumed and will not be propagated to other exception handlers.
+    """
+    def __init__(self, exception_handler):
+        self.exception_handler = exception_handler
+        self.active = True
+
+    def _deactivate(self):
+        self.active = False
+
+    def exit(self, type, value, traceback):
+        if type is not None:
+            return self.exception_handler(type, value, traceback)
+
+    def __enter__(self):
+        self.old_contexts = _state.contexts
+        self.new_contexts = (self.old_contexts[0], self)
+        _state.contexts = self.new_contexts
+
+        return self._deactivate
+
+    def __exit__(self, type, value, traceback):
+        try:
+            if type is not None:
+                return self.exception_handler(type, value, traceback)
+        finally:
+            final_contexts = _state.contexts
+            _state.contexts = self.old_contexts
+
+            if final_contexts is not self.new_contexts:
+                raise StackContextInconsistentError(
+                    'stack_context inconsistency (may be caused by yield '
+                    'within a "with StackContext" block)')
+
+            # Break up a reference to itself to allow for faster GC on CPython.
+            self.new_contexts = None
+
+
+class NullContext(object):
+    """Resets the `StackContext`.
+
+    Useful when creating a shared resource on demand (e.g. an
+    `.AsyncHTTPClient`) where the stack that caused the creating is
+    not relevant to future operations.
+    """
+    def __enter__(self):
+        self.old_contexts = _state.contexts
+        _state.contexts = (tuple(), None)
+
+    def __exit__(self, type, value, traceback):
+        _state.contexts = self.old_contexts
+
+
+def _remove_deactivated(contexts):
+    """Remove deactivated handlers from the chain"""
+    # Clean ctx handlers
+    stack_contexts = tuple([h for h in contexts[0] if h.active])
+
+    # Find new head
+    head = contexts[1]
+    while head is not None and not head.active:
+        head = head.old_contexts[1]
+
+    # Process chain
+    ctx = head
+    while ctx is not None:
+        parent = ctx.old_contexts[1]
+
+        while parent is not None:
+            if parent.active:
+                break
+            ctx.old_contexts = parent.old_contexts
+            parent = parent.old_contexts[1]
+
+        ctx = parent
+
+    return (stack_contexts, head)
+
+
+def wrap(fn):
+    """Returns a callable object that will restore the current `StackContext`
+    when executed.
+
+    Use this whenever saving a callback to be executed later in a
+    different execution context (either in a different thread or
+    asynchronously in the same thread).
+    """
+    # Check if function is already wrapped
+    if fn is None or hasattr(fn, '_wrapped'):
+        return fn
+
+    # Capture current stack head
+    # TODO: Any other better way to store contexts and update them in wrapped function?
+    cap_contexts = [_state.contexts]
+
+    def wrapped(*args, **kwargs):
+        ret = None
+        try:
+            # Capture old state
+            current_state = _state.contexts
+
+            # Remove deactivated items
+            cap_contexts[0] = contexts = _remove_deactivated(cap_contexts[0])
+
+            # Force new state
+            _state.contexts = contexts
+
+            # Current exception
+            exc = (None, None, None)
+            top = None
+
+            # Apply stack contexts
+            last_ctx = 0
+            stack = contexts[0]
+
+            # Apply state
+            for n in stack:
+                try:
+                    n.enter()
+                    last_ctx += 1
+                except:
+                    # Exception happened. Record exception info and store top-most handler
+                    exc = sys.exc_info()
+                    top = n.old_contexts[1]
+
+            # Execute callback if no exception happened while restoring state
+            if top is None:
+                try:
+                    ret = fn(*args, **kwargs)
+                except:
+                    exc = sys.exc_info()
+                    top = contexts[1]
+
+            # If there was exception, try to handle it by going through the exception chain
+            if top is not None:
+                exc = _handle_exception(top, exc)
+            else:
+                # Otherwise take shorter path and run stack contexts in reverse order
+                while last_ctx > 0:
+                    last_ctx -= 1
+                    c = stack[last_ctx]
+
+                    try:
+                        c.exit(*exc)
+                    except:
+                        exc = sys.exc_info()
+                        top = c.old_contexts[1]
+                        break
+                else:
+                    top = None
+
+                # If if exception happened while unrolling, take longer exception handler path
+                if top is not None:
+                    exc = _handle_exception(top, exc)
+
+            # If exception was not handled, raise it
+            if exc != (None, None, None):
+                raise_exc_info(exc)
+        finally:
+            _state.contexts = current_state
+        return ret
+
+    wrapped._wrapped = True
+    return wrapped
+
+
+def _handle_exception(tail, exc):
+    while tail is not None:
+        try:
+            if tail.exit(*exc):
+                exc = (None, None, None)
+        except:
+            exc = sys.exc_info()
+
+        tail = tail.old_contexts[1]
+
+    return exc
+
+
+def run_with_stack_context(context, func):
+    """Run a coroutine ``func`` in the given `StackContext`.
+
+    It is not safe to have a ``yield`` statement within a ``with StackContext``
+    block, so it is difficult to use stack context with `.gen.coroutine`.
+    This helper function runs the function in the correct context while
+    keeping the ``yield`` and ``with`` statements syntactically separate.
+
+    Example::
+
+        @gen.coroutine
+        def incorrect():
+            with StackContext(ctx):
+                # ERROR: this will raise StackContextInconsistentError
+                yield other_coroutine()
+
+        @gen.coroutine
+        def correct():
+            yield run_with_stack_context(StackContext(ctx), other_coroutine)
+
+    .. versionadded:: 3.1
+    """
+    with context:
+        return func()
diff --git a/zmq/eventloop/minitornado/util.py b/zmq/eventloop/minitornado/util.py
new file mode 100644
index 0000000..c1e2eb9
--- /dev/null
+++ b/zmq/eventloop/minitornado/util.py
@@ -0,0 +1,184 @@
+"""Miscellaneous utility functions and classes.
+
+This module is used internally by Tornado.  It is not necessarily expected
+that the functions and classes defined here will be useful to other
+applications, but they are documented here in case they are.
+
+The one public-facing part of this module is the `Configurable` class
+and its `~Configurable.configure` method, which becomes a part of the
+interface of its subclasses, including `.AsyncHTTPClient`, `.IOLoop`,
+and `.Resolver`.
+"""
+
+from __future__ import absolute_import, division, print_function, with_statement
+
+import sys
+
+
+def import_object(name):
+    """Imports an object by name.
+
+    import_object('x') is equivalent to 'import x'.
+    import_object('x.y.z') is equivalent to 'from x.y import z'.
+
+    >>> import tornado.escape
+    >>> import_object('tornado.escape') is tornado.escape
+    True
+    >>> import_object('tornado.escape.utf8') is tornado.escape.utf8
+    True
+    >>> import_object('tornado') is tornado
+    True
+    >>> import_object('tornado.missing_module')
+    Traceback (most recent call last):
+        ...
+    ImportError: No module named missing_module
+    """
+    if name.count('.') == 0:
+        return __import__(name, None, None)
+
+    parts = name.split('.')
+    obj = __import__('.'.join(parts[:-1]), None, None, [parts[-1]], 0)
+    try:
+        return getattr(obj, parts[-1])
+    except AttributeError:
+        raise ImportError("No module named %s" % parts[-1])
+
+
+# Fake unicode literal support:  Python 3.2 doesn't have the u'' marker for
+# literal strings, and alternative solutions like "from __future__ import
+# unicode_literals" have other problems (see PEP 414).  u() can be applied
+# to ascii strings that include \u escapes (but they must not contain
+# literal non-ascii characters).
+if type('') is not type(b''):
+    def u(s):
+        return s
+    bytes_type = bytes
+    unicode_type = str
+    basestring_type = str
+else:
+    def u(s):
+        return s.decode('unicode_escape')
+    bytes_type = str
+    unicode_type = unicode
+    basestring_type = basestring
+
+
+if sys.version_info > (3,):
+    exec("""
+def raise_exc_info(exc_info):
+    raise exc_info[1].with_traceback(exc_info[2])
+
+def exec_in(code, glob, loc=None):
+    if isinstance(code, str):
+        code = compile(code, '<string>', 'exec', dont_inherit=True)
+    exec(code, glob, loc)
+""")
+else:
+    exec("""
+def raise_exc_info(exc_info):
+    raise exc_info[0], exc_info[1], exc_info[2]
+
+def exec_in(code, glob, loc=None):
+    if isinstance(code, basestring):
+        # exec(string) inherits the caller's future imports; compile
+        # the string first to prevent that.
+        code = compile(code, '<string>', 'exec', dont_inherit=True)
+    exec code in glob, loc
+""")
+
+
+class Configurable(object):
+    """Base class for configurable interfaces.
+
+    A configurable interface is an (abstract) class whose constructor
+    acts as a factory function for one of its implementation subclasses.
+    The implementation subclass as well as optional keyword arguments to
+    its initializer can be set globally at runtime with `configure`.
+
+    By using the constructor as the factory method, the interface
+    looks like a normal class, `isinstance` works as usual, etc.  This
+    pattern is most useful when the choice of implementation is likely
+    to be a global decision (e.g. when `~select.epoll` is available,
+    always use it instead of `~select.select`), or when a
+    previously-monolithic class has been split into specialized
+    subclasses.
+
+    Configurable subclasses must define the class methods
+    `configurable_base` and `configurable_default`, and use the instance
+    method `initialize` instead of ``__init__``.
+    """
+    __impl_class = None
+    __impl_kwargs = None
+
+    def __new__(cls, **kwargs):
+        base = cls.configurable_base()
+        args = {}
+        if cls is base:
+            impl = cls.configured_class()
+            if base.__impl_kwargs:
+                args.update(base.__impl_kwargs)
+        else:
+            impl = cls
+        args.update(kwargs)
+        instance = super(Configurable, cls).__new__(impl)
+        # initialize vs __init__ chosen for compatiblity with AsyncHTTPClient
+        # singleton magic.  If we get rid of that we can switch to __init__
+        # here too.
+        instance.initialize(**args)
+        return instance
+
+    @classmethod
+    def configurable_base(cls):
+        """Returns the base class of a configurable hierarchy.
+
+        This will normally return the class in which it is defined.
+        (which is *not* necessarily the same as the cls classmethod parameter).
+        """
+        raise NotImplementedError()
+
+    @classmethod
+    def configurable_default(cls):
+        """Returns the implementation class to be used if none is configured."""
+        raise NotImplementedError()
+
+    def initialize(self):
+        """Initialize a `Configurable` subclass instance.
+
+        Configurable classes should use `initialize` instead of ``__init__``.
+        """
+
+    @classmethod
+    def configure(cls, impl, **kwargs):
+        """Sets the class to use when the base class is instantiated.
+
+        Keyword arguments will be saved and added to the arguments passed
+        to the constructor.  This can be used to set global defaults for
+        some parameters.
+        """
+        base = cls.configurable_base()
+        if isinstance(impl, (unicode_type, bytes_type)):
+            impl = import_object(impl)
+        if impl is not None and not issubclass(impl, cls):
+            raise ValueError("Invalid subclass of %s" % cls)
+        base.__impl_class = impl
+        base.__impl_kwargs = kwargs
+
+    @classmethod
+    def configured_class(cls):
+        """Returns the currently configured class."""
+        base = cls.configurable_base()
+        if cls.__impl_class is None:
+            base.__impl_class = cls.configurable_default()
+        return base.__impl_class
+
+    @classmethod
+    def _save_configuration(cls):
+        base = cls.configurable_base()
+        return (base.__impl_class, base.__impl_kwargs)
+
+    @classmethod
+    def _restore_configuration(cls, saved):
+        base = cls.configurable_base()
+        base.__impl_class = saved[0]
+        base.__impl_kwargs = saved[1]
+
diff --git a/zmq/eventloop/zmqstream.py b/zmq/eventloop/zmqstream.py
new file mode 100644
index 0000000..86a97e4
--- /dev/null
+++ b/zmq/eventloop/zmqstream.py
@@ -0,0 +1,529 @@
+#
+# Copyright 2009 Facebook
+#
+# Licensed under the Apache License, Version 2.0 (the "License"); you may
+# not use this file except in compliance with the License. You may obtain
+# a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+# License for the specific language governing permissions and limitations
+# under the License.
+
+"""A utility class to send to and recv from a non-blocking socket."""
+
+from __future__ import with_statement
+
+import sys
+
+import zmq
+from zmq.utils import jsonapi
+
+try:
+    import cPickle as pickle
+except ImportError:
+    import pickle
+
+from .ioloop import IOLoop
+
+try:
+    # gen_log will only import from >= 3.0
+    from tornado.log import gen_log
+    from tornado import stack_context
+except ImportError:
+    from .minitornado.log import gen_log
+    from .minitornado import stack_context
+
+try:
+    from queue import Queue
+except ImportError:
+    from Queue import Queue
+
+from zmq.utils.strtypes import bytes, unicode, basestring
+
+try:
+    callable
+except NameError:
+    callable = lambda obj: hasattr(obj, '__call__')
+
+
+class ZMQStream(object):
+    """A utility class to register callbacks when a zmq socket sends and receives
+    
+    For use with zmq.eventloop.ioloop
+
+    There are three main methods
+    
+    Methods:
+    
+    * **on_recv(callback, copy=True):**
+        register a callback to be run every time the socket has something to receive
+    * **on_send(callback):**
+        register a callback to be run every time you call send
+    * **send(self, msg, flags=0, copy=False, callback=None):**
+        perform a send that will trigger the callback
+        if callback is passed, on_send is also called.
+        
+        There are also send_multipart(), send_json(), send_pyobj()
+    
+    Three other methods for deactivating the callbacks:
+    
+    * **stop_on_recv():**
+        turn off the recv callback
+    * **stop_on_send():**
+        turn off the send callback
+    
+    which simply call ``on_<evt>(None)``.
+    
+    The entire socket interface, excluding direct recv methods, is also
+    provided, primarily through direct-linking the methods.
+    e.g.
+    
+    >>> stream.bind is stream.socket.bind
+    True
+    
+    """
+    
+    socket = None
+    io_loop = None
+    poller = None
+    
+    def __init__(self, socket, io_loop=None):
+        self.socket = socket
+        self.io_loop = io_loop or IOLoop.instance()
+        self.poller = zmq.Poller()
+        
+        self._send_queue = Queue()
+        self._recv_callback = None
+        self._send_callback = None
+        self._close_callback = None
+        self._recv_copy = False
+        self._flushed = False
+        
+        self._state = self.io_loop.ERROR
+        self._init_io_state()
+        
+        # shortcircuit some socket methods
+        self.bind = self.socket.bind
+        self.bind_to_random_port = self.socket.bind_to_random_port
+        self.connect = self.socket.connect
+        self.setsockopt = self.socket.setsockopt
+        self.getsockopt = self.socket.getsockopt
+        self.setsockopt_string = self.socket.setsockopt_string
+        self.getsockopt_string = self.socket.getsockopt_string
+        self.setsockopt_unicode = self.socket.setsockopt_unicode
+        self.getsockopt_unicode = self.socket.getsockopt_unicode
+    
+    
+    def stop_on_recv(self):
+        """Disable callback and automatic receiving."""
+        return self.on_recv(None)
+    
+    def stop_on_send(self):
+        """Disable callback on sending."""
+        return self.on_send(None)
+    
+    def stop_on_err(self):
+        """DEPRECATED, does nothing"""
+        gen_log.warn("on_err does nothing, and will be removed")
+    
+    def on_err(self, callback):
+        """DEPRECATED, does nothing"""
+        gen_log.warn("on_err does nothing, and will be removed")
+    
+    def on_recv(self, callback, copy=True):
+        """Register a callback for when a message is ready to recv.
+        
+        There can be only one callback registered at a time, so each
+        call to `on_recv` replaces previously registered callbacks.
+        
+        on_recv(None) disables recv event polling.
+        
+        Use on_recv_stream(callback) instead, to register a callback that will receive
+        both this ZMQStream and the message, instead of just the message.
+        
+        Parameters
+        ----------
+        
+        callback : callable
+            callback must take exactly one argument, which will be a
+            list, as returned by socket.recv_multipart()
+            if callback is None, recv callbacks are disabled.
+        copy : bool
+            copy is passed directly to recv, so if copy is False,
+            callback will receive Message objects. If copy is True,
+            then callback will receive bytes/str objects.
+        
+        Returns : None
+        """
+        
+        self._check_closed()
+        assert callback is None or callable(callback)
+        self._recv_callback = stack_context.wrap(callback)
+        self._recv_copy = copy
+        if callback is None:
+            self._drop_io_state(self.io_loop.READ)
+        else:
+            self._add_io_state(self.io_loop.READ)
+    
+    def on_recv_stream(self, callback, copy=True):
+        """Same as on_recv, but callback will get this stream as first argument
+        
+        callback must take exactly two arguments, as it will be called as::
+        
+            callback(stream, msg)
+        
+        Useful when a single callback should be used with multiple streams.
+        """
+        if callback is None:
+            self.stop_on_recv()
+        else:
+            self.on_recv(lambda msg: callback(self, msg), copy=copy)
+    
+    def on_send(self, callback):
+        """Register a callback to be called on each send
+        
+        There will be two arguments::
+        
+            callback(msg, status)
+        
+        * `msg` will be the list of sendable objects that was just sent
+        * `status` will be the return result of socket.send_multipart(msg) -
+          MessageTracker or None.
+        
+        Non-copying sends return a MessageTracker object whose
+        `done` attribute will be True when the send is complete.
+        This allows users to track when an object is safe to write to
+        again.
+        
+        The second argument will always be None if copy=True
+        on the send.
+        
+        Use on_send_stream(callback) to register a callback that will be passed
+        this ZMQStream as the first argument, in addition to the other two.
+        
+        on_send(None) disables recv event polling.
+        
+        Parameters
+        ----------
+        
+        callback : callable
+            callback must take exactly two arguments, which will be
+            the message being sent (always a list),
+            and the return result of socket.send_multipart(msg) -
+            MessageTracker or None.
+            
+            if callback is None, send callbacks are disabled.
+        """
+        
+        self._check_closed()
+        assert callback is None or callable(callback)
+        self._send_callback = stack_context.wrap(callback)
+        
+    
+    def on_send_stream(self, callback):
+        """Same as on_send, but callback will get this stream as first argument
+        
+        Callback will be passed three arguments::
+        
+            callback(stream, msg, status)
+        
+        Useful when a single callback should be used with multiple streams.
+        """
+        if callback is None:
+            self.stop_on_send()
+        else:
+            self.on_send(lambda msg, status: callback(self, msg, status))
+        
+        
+    def send(self, msg, flags=0, copy=True, track=False, callback=None):
+        """Send a message, optionally also register a new callback for sends.
+        See zmq.socket.send for details.
+        """
+        return self.send_multipart([msg], flags=flags, copy=copy, track=track, callback=callback)
+
+    def send_multipart(self, msg, flags=0, copy=True, track=False, callback=None):
+        """Send a multipart message, optionally also register a new callback for sends.
+        See zmq.socket.send_multipart for details.
+        """
+        kwargs = dict(flags=flags, copy=copy, track=track)
+        self._send_queue.put((msg, kwargs))
+        callback = callback or self._send_callback
+        if callback is not None:
+            self.on_send(callback)
+        else:
+            # noop callback
+            self.on_send(lambda *args: None)
+        self._add_io_state(self.io_loop.WRITE)
+    
+    def send_string(self, u, flags=0, encoding='utf-8', callback=None):
+        """Send a unicode message with an encoding.
+        See zmq.socket.send_unicode for details.
+        """
+        if not isinstance(u, basestring):
+            raise TypeError("unicode/str objects only")
+        return self.send(u.encode(encoding), flags=flags, callback=callback)
+    
+    send_unicode = send_string
+    
+    def send_json(self, obj, flags=0, callback=None):
+        """Send json-serialized version of an object.
+        See zmq.socket.send_json for details.
+        """
+        if jsonapi is None:
+            raise ImportError('jsonlib{1,2}, json or simplejson library is required.')
+        else:
+            msg = jsonapi.dumps(obj)
+            return self.send(msg, flags=flags, callback=callback)
+
+    def send_pyobj(self, obj, flags=0, protocol=-1, callback=None):
+        """Send a Python object as a message using pickle to serialize.
+
+        See zmq.socket.send_json for details.
+        """
+        msg = pickle.dumps(obj, protocol)
+        return self.send(msg, flags, callback=callback)
+    
+    def _finish_flush(self):
+        """callback for unsetting _flushed flag."""
+        self._flushed = False
+    
+    def flush(self, flag=zmq.POLLIN|zmq.POLLOUT, limit=None):
+        """Flush pending messages.
+
+        This method safely handles all pending incoming and/or outgoing messages,
+        bypassing the inner loop, passing them to the registered callbacks.
+
+        A limit can be specified, to prevent blocking under high load.
+
+        flush will return the first time ANY of these conditions are met:
+            * No more events matching the flag are pending.
+            * the total number of events handled reaches the limit.
+
+        Note that if ``flag|POLLIN != 0``, recv events will be flushed even if no callback
+        is registered, unlike normal IOLoop operation. This allows flush to be
+        used to remove *and ignore* incoming messages.
+
+        Parameters
+        ----------
+        flag : int, default=POLLIN|POLLOUT
+                0MQ poll flags.
+                If flag|POLLIN,  recv events will be flushed.
+                If flag|POLLOUT, send events will be flushed.
+                Both flags can be set at once, which is the default.
+        limit : None or int, optional
+                The maximum number of messages to send or receive.
+                Both send and recv count against this limit.
+
+        Returns
+        -------
+        int : count of events handled (both send and recv)
+        """
+        self._check_closed()
+        # unset self._flushed, so callbacks will execute, in case flush has
+        # already been called this iteration
+        already_flushed = self._flushed
+        self._flushed = False
+        # initialize counters
+        count = 0
+        def update_flag():
+            """Update the poll flag, to prevent registering POLLOUT events
+            if we don't have pending sends."""
+            return flag & zmq.POLLIN | (self.sending() and flag & zmq.POLLOUT)
+        flag = update_flag()
+        if not flag:
+            # nothing to do
+            return 0
+        self.poller.register(self.socket, flag)
+        events = self.poller.poll(0)
+        while events and (not limit or count < limit):
+            s,event = events[0]
+            if event & zmq.POLLIN: # receiving
+                self._handle_recv()
+                count += 1
+                if self.socket is None:
+                    # break if socket was closed during callback
+                    break
+            if event & zmq.POLLOUT and self.sending():
+                self._handle_send()
+                count += 1
+                if self.socket is None:
+                    # break if socket was closed during callback
+                    break
+            
+            flag = update_flag()
+            if flag:
+                self.poller.register(self.socket, flag)
+                events = self.poller.poll(0)
+            else:
+                events = []
+        if count: # only bypass loop if we actually flushed something
+            # skip send/recv callbacks this iteration
+            self._flushed = True
+            # reregister them at the end of the loop
+            if not already_flushed: # don't need to do it again
+                self.io_loop.add_callback(self._finish_flush)
+        elif already_flushed:
+            self._flushed = True
+
+        # update ioloop poll state, which may have changed
+        self._rebuild_io_state()
+        return count
+    
+    def set_close_callback(self, callback):
+        """Call the given callback when the stream is closed."""
+        self._close_callback = stack_context.wrap(callback)
+    
+    def close(self, linger=None):
+        """Close this stream."""
+        if self.socket is not None:
+            self.io_loop.remove_handler(self.socket)
+            self.socket.close(linger)
+            self.socket = None
+            if self._close_callback:
+                self._run_callback(self._close_callback)
+
+    def receiving(self):
+        """Returns True if we are currently receiving from the stream."""
+        return self._recv_callback is not None
+
+    def sending(self):
+        """Returns True if we are currently sending to the stream."""
+        return not self._send_queue.empty()
+
+    def closed(self):
+        return self.socket is None
+
+    def _run_callback(self, callback, *args, **kwargs):
+        """Wrap running callbacks in try/except to allow us to
+        close our socket."""
+        try:
+            # Use a NullContext to ensure that all StackContexts are run
+            # inside our blanket exception handler rather than outside.
+            with stack_context.NullContext():
+                callback(*args, **kwargs)
+        except:
+            gen_log.error("Uncaught exception, closing connection.",
+                          exc_info=True)
+            # Close the socket on an uncaught exception from a user callback
+            # (It would eventually get closed when the socket object is
+            # gc'd, but we don't want to rely on gc happening before we
+            # run out of file descriptors)
+            self.close()
+            # Re-raise the exception so that IOLoop.handle_callback_exception
+            # can see it and log the error
+            raise
+
+    def _handle_events(self, fd, events):
+        """This method is the actual handler for IOLoop, that gets called whenever
+        an event on my socket is posted. It dispatches to _handle_recv, etc."""
+        # print "handling events"
+        if not self.socket:
+            gen_log.warning("Got events for closed stream %s", fd)
+            return
+        try:
+            # dispatch events:
+            if events & IOLoop.ERROR:
+                gen_log.error("got POLLERR event on ZMQStream, which doesn't make sense")
+                return
+            if events & IOLoop.READ:
+                self._handle_recv()
+                if not self.socket:
+                    return
+            if events & IOLoop.WRITE:
+                self._handle_send()
+                if not self.socket:
+                    return
+
+            # rebuild the poll state
+            self._rebuild_io_state()
+        except:
+            gen_log.error("Uncaught exception, closing connection.",
+                          exc_info=True)
+            self.close()
+            raise
+            
+    def _handle_recv(self):
+        """Handle a recv event."""
+        if self._flushed:
+            return
+        try:
+            msg = self.socket.recv_multipart(zmq.NOBLOCK, copy=self._recv_copy)
+        except zmq.ZMQError as e:
+            if e.errno == zmq.EAGAIN:
+                # state changed since poll event
+                pass
+            else:
+                gen_log.error("RECV Error: %s"%zmq.strerror(e.errno))
+        else:
+            if self._recv_callback:
+                callback = self._recv_callback
+                # self._recv_callback = None
+                self._run_callback(callback, msg)
+                
+        # self.update_state()
+        
+
+    def _handle_send(self):
+        """Handle a send event."""
+        if self._flushed:
+            return
+        if not self.sending():
+            gen_log.error("Shouldn't have handled a send event")
+            return
+        
+        msg, kwargs = self._send_queue.get()
+        try:
+            status = self.socket.send_multipart(msg, **kwargs)
+        except zmq.ZMQError as e:
+            gen_log.error("SEND Error: %s", e)
+            status = e
+        if self._send_callback:
+            callback = self._send_callback
+            self._run_callback(callback, msg, status)
+        
+        # self.update_state()
+    
+    def _check_closed(self):
+        if not self.socket:
+            raise IOError("Stream is closed")
+    
+    def _rebuild_io_state(self):
+        """rebuild io state based on self.sending() and receiving()"""
+        if self.socket is None:
+            return
+        state = self.io_loop.ERROR
+        if self.receiving():
+            state |= self.io_loop.READ
+        if self.sending():
+            state |= self.io_loop.WRITE
+        if state != self._state:
+            self._state = state
+            self._update_handler(state)
+    
+    def _add_io_state(self, state):
+        """Add io_state to poller."""
+        if not self._state & state:
+            self._state = self._state | state
+            self._update_handler(self._state)
+    
+    def _drop_io_state(self, state):
+        """Stop poller from watching an io_state."""
+        if self._state & state:
+            self._state = self._state & (~state)
+            self._update_handler(self._state)
+    
+    def _update_handler(self, state):
+        """Update IOLoop handler with state."""
+        if self.socket is None:
+            return
+        self.io_loop.update_handler(self.socket, state)
+    
+    def _init_io_state(self):
+        """initialize the ioloop event handler"""
+        with stack_context.NullContext():
+            self.io_loop.add_handler(self.socket, self._handle_events, self._state)
+
diff --git a/zmq/green/__init__.py b/zmq/green/__init__.py
new file mode 100644
index 0000000..ff7e596
--- /dev/null
+++ b/zmq/green/__init__.py
@@ -0,0 +1,40 @@
+# -*- coding: utf-8 -*-
+#-----------------------------------------------------------------------------
+#  Copyright (C) 2011-2012 Travis Cline
+#
+#  This file is part of pyzmq
+#  It is adapted from upstream project zeromq_gevent under the New BSD License
+#
+#  Distributed under the terms of the New BSD License.  The full license is in
+#  the file COPYING.BSD, distributed as part of this software.
+#-----------------------------------------------------------------------------
+
+"""zmq.green - gevent compatibility with zeromq.
+
+Usage
+-----
+
+Instead of importing zmq directly, do so in the following manner:
+
+..
+
+    import zmq.green as zmq
+
+
+Any calls that would have blocked the current thread will now only block the
+current green thread.
+
+This compatibility is accomplished by ensuring the nonblocking flag is set
+before any blocking operation and the ØMQ file descriptor is polled internally
+to trigger needed events.
+"""
+
+from zmq import *
+from zmq.green.core import _Context, _Socket
+from zmq.green.poll import _Poller
+Context = _Context
+Socket = _Socket
+Poller = _Poller
+
+from zmq.green.device import device
+
diff --git a/zmq/green/core.py b/zmq/green/core.py
new file mode 100644
index 0000000..9fc73e3
--- /dev/null
+++ b/zmq/green/core.py
@@ -0,0 +1,287 @@
+#-----------------------------------------------------------------------------
+#  Copyright (C) 2011-2012 Travis Cline
+#
+#  This file is part of pyzmq
+#  It is adapted from upstream project zeromq_gevent under the New BSD License
+#
+#  Distributed under the terms of the New BSD License.  The full license is in
+#  the file COPYING.BSD, distributed as part of this software.
+#-----------------------------------------------------------------------------
+
+"""This module wraps the :class:`Socket` and :class:`Context` found in :mod:`pyzmq <zmq>` to be non blocking
+"""
+
+from __future__ import print_function
+
+import sys
+import time
+import warnings
+
+import zmq
+
+from zmq import Context as _original_Context
+from zmq import Socket as _original_Socket
+from .poll import _Poller
+
+import gevent
+from gevent.event import AsyncResult
+from gevent.hub import get_hub
+
+if hasattr(zmq, 'RCVTIMEO'):
+    TIMEOS = (zmq.RCVTIMEO, zmq.SNDTIMEO)
+else:
+    TIMEOS = ()
+
+def _stop(evt):
+    """simple wrapper for stopping an Event, allowing for method rename in gevent 1.0"""
+    try:
+        evt.stop()
+    except AttributeError as e:
+        # gevent<1.0 compat
+        evt.cancel()
+
+class _Socket(_original_Socket):
+    """Green version of :class:`zmq.Socket`
+
+    The following methods are overridden:
+
+        * send
+        * recv
+
+    To ensure that the ``zmq.NOBLOCK`` flag is set and that sending or receiving
+    is deferred to the hub if a ``zmq.EAGAIN`` (retry) error is raised.
+    
+    The `__state_changed` method is triggered when the zmq.FD for the socket is
+    marked as readable and triggers the necessary read and write events (which
+    are waited for in the recv and send methods).
+
+    Some double underscore prefixes are used to minimize pollution of
+    :class:`zmq.Socket`'s namespace.
+    """
+    __in_send_multipart = False
+    __in_recv_multipart = False
+    __writable = None
+    __readable = None
+    _state_event = None
+    _gevent_bug_timeout = 11.6 # timeout for not trusting gevent
+    _debug_gevent = False # turn on if you think gevent is missing events
+    _poller_class = _Poller
+    
+    def __init__(self, context, socket_type):
+        _original_Socket.__init__(self, context, socket_type)
+        self.__in_send_multipart = False
+        self.__in_recv_multipart = False
+        self.__setup_events()
+        
+
+    def __del__(self):
+        self.close()
+
+    def close(self, linger=None):
+        super(_Socket, self).close(linger)
+        self.__cleanup_events()
+
+    def __cleanup_events(self):
+        # close the _state_event event, keeps the number of active file descriptors down
+        if getattr(self, '_state_event', None):
+            _stop(self._state_event)
+            self._state_event = None
+        # if the socket has entered a close state resume any waiting greenlets
+        self.__writable.set()
+        self.__readable.set()
+
+    def __setup_events(self):
+        self.__readable = AsyncResult()
+        self.__writable = AsyncResult()
+        self.__readable.set()
+        self.__writable.set()
+        
+        try:
+            self._state_event = get_hub().loop.io(self.getsockopt(zmq.FD), 1) # read state watcher
+            self._state_event.start(self.__state_changed)
+        except AttributeError:
+            # for gevent<1.0 compatibility
+            from gevent.core import read_event
+            self._state_event = read_event(self.getsockopt(zmq.FD), self.__state_changed, persist=True)
+
+    def __state_changed(self, event=None, _evtype=None):
+        if self.closed:
+            self.__cleanup_events()
+            return
+        try:
+            # avoid triggering __state_changed from inside __state_changed
+            events = super(_Socket, self).getsockopt(zmq.EVENTS)
+        except zmq.ZMQError as exc:
+            self.__writable.set_exception(exc)
+            self.__readable.set_exception(exc)
+        else:
+            if events & zmq.POLLOUT:
+                self.__writable.set()
+            if events & zmq.POLLIN:
+                self.__readable.set()
+
+    def _wait_write(self):
+        assert self.__writable.ready(), "Only one greenlet can be waiting on this event"
+        self.__writable = AsyncResult()
+        # timeout is because libzmq cannot be trusted to properly signal a new send event:
+        # this is effectively a maximum poll interval of 1s
+        tic = time.time()
+        dt = self._gevent_bug_timeout
+        if dt:
+            timeout = gevent.Timeout(seconds=dt)
+        else:
+            timeout = None
+        try:
+            if timeout:
+                timeout.start()
+            self.__writable.get(block=True)
+        except gevent.Timeout as t:
+            if t is not timeout:
+                raise
+            toc = time.time()
+            # gevent bug: get can raise timeout even on clean return
+            # don't display zmq bug warning for gevent bug (this is getting ridiculous)
+            if self._debug_gevent and timeout and toc-tic > dt and \
+                    self.getsockopt(zmq.EVENTS) & zmq.POLLOUT:
+                print("BUG: gevent may have missed a libzmq send event on %i!" % self.FD, file=sys.stderr)
+        finally:
+            if timeout:
+                timeout.cancel()
+            self.__writable.set()
+
+    def _wait_read(self):
+        assert self.__readable.ready(), "Only one greenlet can be waiting on this event"
+        self.__readable = AsyncResult()
+        # timeout is because libzmq cannot always be trusted to play nice with libevent.
+        # I can only confirm that this actually happens for send, but lets be symmetrical
+        # with our dirty hacks.
+        # this is effectively a maximum poll interval of 1s
+        tic = time.time()
+        dt = self._gevent_bug_timeout
+        if dt:
+            timeout = gevent.Timeout(seconds=dt)
+        else:
+            timeout = None
+        try:
+            if timeout:
+                timeout.start()
+            self.__readable.get(block=True)
+        except gevent.Timeout as t:
+            if t is not timeout:
+                raise
+            toc = time.time()
+            # gevent bug: get can raise timeout even on clean return
+            # don't display zmq bug warning for gevent bug (this is getting ridiculous)
+            if self._debug_gevent and timeout and toc-tic > dt and \
+                    self.getsockopt(zmq.EVENTS) & zmq.POLLIN:
+                print("BUG: gevent may have missed a libzmq recv event on %i!" % self.FD, file=sys.stderr)
+        finally:
+            if timeout:
+                timeout.cancel()
+            self.__readable.set()
+
+    def send(self, data, flags=0, copy=True, track=False):
+        """send, which will only block current greenlet
+        
+        state_changed always fires exactly once (success or fail) at the
+        end of this method.
+        """
+        
+        # if we're given the NOBLOCK flag act as normal and let the EAGAIN get raised
+        if flags & zmq.NOBLOCK:
+            try:
+                msg = super(_Socket, self).send(data, flags, copy, track)
+            finally:
+                if not self.__in_send_multipart:
+                    self.__state_changed()
+            return msg
+        # ensure the zmq.NOBLOCK flag is part of flags
+        flags |= zmq.NOBLOCK
+        while True: # Attempt to complete this operation indefinitely, blocking the current greenlet
+            try:
+                # attempt the actual call
+                msg = super(_Socket, self).send(data, flags, copy, track)
+            except zmq.ZMQError as e:
+                # if the raised ZMQError is not EAGAIN, reraise
+                if e.errno != zmq.EAGAIN:
+                    if not self.__in_send_multipart:
+                        self.__state_changed()
+                    raise
+            else:
+                if not self.__in_send_multipart:
+                    self.__state_changed()
+                return msg
+            # defer to the event loop until we're notified the socket is writable
+            self._wait_write()
+
+    def recv(self, flags=0, copy=True, track=False):
+        """recv, which will only block current greenlet
+        
+        state_changed always fires exactly once (success or fail) at the
+        end of this method.
+        """
+        if flags & zmq.NOBLOCK:
+            try:
+                msg = super(_Socket, self).recv(flags, copy, track)
+            finally:
+                if not self.__in_recv_multipart:
+                    self.__state_changed()
+            return msg
+        
+        flags |= zmq.NOBLOCK
+        while True:
+            try:
+                msg = super(_Socket, self).recv(flags, copy, track)
+            except zmq.ZMQError as e:
+                if e.errno != zmq.EAGAIN:
+                    if not self.__in_recv_multipart:
+                        self.__state_changed()
+                    raise
+            else:
+                if not self.__in_recv_multipart:
+                    self.__state_changed()
+                return msg
+            self._wait_read()
+    
+    def send_multipart(self, *args, **kwargs):
+        """wrap send_multipart to prevent state_changed on each partial send"""
+        self.__in_send_multipart = True
+        try:
+            msg = super(_Socket, self).send_multipart(*args, **kwargs)
+        finally:
+            self.__in_send_multipart = False
+            self.__state_changed()
+        return msg
+    
+    def recv_multipart(self, *args, **kwargs):
+        """wrap recv_multipart to prevent state_changed on each partial recv"""
+        self.__in_recv_multipart = True
+        try:
+            msg = super(_Socket, self).recv_multipart(*args, **kwargs)
+        finally:
+            self.__in_recv_multipart = False
+            self.__state_changed()
+        return msg
+    
+    def get(self, opt):
+        """trigger state_changed on getsockopt(EVENTS)"""
+        if opt in TIMEOS:
+            warnings.warn("TIMEO socket options have no effect in zmq.green", UserWarning)
+        optval = super(_Socket, self).get(opt)
+        if opt == zmq.EVENTS:
+            self.__state_changed()
+        return optval
+    
+    def set(self, opt, val):
+        """set socket option"""
+        if opt in TIMEOS:
+            warnings.warn("TIMEO socket options have no effect in zmq.green", UserWarning)
+        return super(_Socket, self).set(opt, val)
+
+
+class _Context(_original_Context):
+    """Replacement for :class:`zmq.Context`
+
+    Ensures that the greened Socket above is used in calls to `socket`.
+    """
+    _socket_class = _Socket
diff --git a/zmq/green/device.py b/zmq/green/device.py
new file mode 100644
index 0000000..4b07023
--- /dev/null
+++ b/zmq/green/device.py
@@ -0,0 +1,32 @@
+# Copyright (C) PyZMQ Developers
+# Distributed under the terms of the Modified BSD License.
+
+import zmq
+from zmq.green import Poller
+
+def device(device_type, isocket, osocket):
+    """Start a zeromq device (gevent-compatible).
+    
+    Unlike the true zmq.device, this does not release the GIL.
+
+    Parameters
+    ----------
+    device_type : (QUEUE, FORWARDER, STREAMER)
+        The type of device to start (ignored).
+    isocket : Socket
+        The Socket instance for the incoming traffic.
+    osocket : Socket
+        The Socket instance for the outbound traffic.
+    """
+    p = Poller()
+    if osocket == -1:
+        osocket = isocket
+    p.register(isocket, zmq.POLLIN)
+    p.register(osocket, zmq.POLLIN)
+    
+    while True:
+        events = dict(p.poll())
+        if isocket in events:
+            osocket.send_multipart(isocket.recv_multipart())
+        if osocket in events:
+            isocket.send_multipart(osocket.recv_multipart())
diff --git a/zmq/green/eventloop/__init__.py b/zmq/green/eventloop/__init__.py
new file mode 100644
index 0000000..c5150ef
--- /dev/null
+++ b/zmq/green/eventloop/__init__.py
@@ -0,0 +1,3 @@
+from zmq.green.eventloop.ioloop import IOLoop
+
+__all__ = ['IOLoop']
\ No newline at end of file
diff --git a/zmq/green/eventloop/ioloop.py b/zmq/green/eventloop/ioloop.py
new file mode 100644
index 0000000..e12fd5e
--- /dev/null
+++ b/zmq/green/eventloop/ioloop.py
@@ -0,0 +1,33 @@
+from zmq.eventloop.ioloop import *
+from zmq.green import Poller
+
+RealIOLoop = IOLoop
+RealZMQPoller = ZMQPoller
+
+class IOLoop(RealIOLoop):
+    
+    def initialize(self, impl=None):
+        impl = _poll() if impl is None else impl
+        super(IOLoop, self).initialize(impl)
+
+    @staticmethod
+    def instance():
+        """Returns a global `IOLoop` instance.
+        
+        Most applications have a single, global `IOLoop` running on the
+        main thread.  Use this method to get this instance from
+        another thread.  To get the current thread's `IOLoop`, use `current()`.
+        """
+        # install this class as the active IOLoop implementation
+        # when using tornado 3
+        if tornado_version >= (3,):
+            PollIOLoop.configure(IOLoop)
+        return PollIOLoop.instance()
+
+
+class ZMQPoller(RealZMQPoller):
+    """gevent-compatible version of ioloop.ZMQPoller"""
+    def __init__(self):
+        self._poller = Poller()
+
+_poll = ZMQPoller
diff --git a/zmq/green/eventloop/zmqstream.py b/zmq/green/eventloop/zmqstream.py
new file mode 100644
index 0000000..90fbd1f
--- /dev/null
+++ b/zmq/green/eventloop/zmqstream.py
@@ -0,0 +1,11 @@
+from zmq.eventloop.zmqstream import *
+
+from zmq.green.eventloop.ioloop import IOLoop
+
+RealZMQStream = ZMQStream
+
+class ZMQStream(RealZMQStream):
+    
+    def __init__(self, socket, io_loop=None):
+        io_loop = io_loop or IOLoop.instance()
+        super(ZMQStream, self).__init__(socket, io_loop=io_loop)
diff --git a/zmq/green/poll.py b/zmq/green/poll.py
new file mode 100644
index 0000000..8f01612
--- /dev/null
+++ b/zmq/green/poll.py
@@ -0,0 +1,95 @@
+import zmq
+import gevent
+from gevent import select
+
+from zmq import Poller as _original_Poller
+
+
+class _Poller(_original_Poller):
+    """Replacement for :class:`zmq.Poller`
+
+    Ensures that the greened Poller below is used in calls to
+    :meth:`zmq.Poller.poll`.
+    """
+    _gevent_bug_timeout = 1.33 # minimum poll interval, for working around gevent bug
+
+    def _get_descriptors(self):
+        """Returns three elements tuple with socket descriptors ready
+        for gevent.select.select
+        """
+        rlist = []
+        wlist = []
+        xlist = []
+
+        for socket, flags in self.sockets:
+            if isinstance(socket, zmq.Socket):
+                rlist.append(socket.getsockopt(zmq.FD))
+                continue
+            elif isinstance(socket, int):
+                fd = socket
+            elif hasattr(socket, 'fileno'):
+                try:
+                    fd = int(socket.fileno())
+                except:
+                    raise ValueError('fileno() must return an valid integer fd')
+            else:
+                raise TypeError('Socket must be a 0MQ socket, an integer fd '
+                                'or have a fileno() method: %r' % socket)
+
+            if flags & zmq.POLLIN:
+                rlist.append(fd)
+            if flags & zmq.POLLOUT:
+                wlist.append(fd)
+            if flags & zmq.POLLERR:
+                xlist.append(fd)
+
+        return (rlist, wlist, xlist)
+
+    def poll(self, timeout=-1):
+        """Overridden method to ensure that the green version of
+        Poller is used.
+
+        Behaves the same as :meth:`zmq.core.Poller.poll`
+        """
+
+        if timeout is None:
+            timeout = -1
+
+        if timeout < 0:
+            timeout = -1
+
+        rlist = None
+        wlist = None
+        xlist = None
+
+        if timeout > 0:
+            tout = gevent.Timeout.start_new(timeout/1000.0)
+
+        try:
+            # Loop until timeout or events available
+            rlist, wlist, xlist = self._get_descriptors()
+            while True:
+                events = super(_Poller, self).poll(0)
+                if events or timeout == 0:
+                    return events
+
+                # wait for activity on sockets in a green way
+                # set a minimum poll frequency,
+                # because gevent < 1.0 cannot be trusted to catch edge-triggered FD events
+                _bug_timeout = gevent.Timeout.start_new(self._gevent_bug_timeout)
+                try:
+                    select.select(rlist, wlist, xlist)
+                except gevent.Timeout as t:
+                    if t is not _bug_timeout:
+                        raise
+                finally:
+                    _bug_timeout.cancel()
+
+        except gevent.Timeout as t:
+            if t is not tout:
+                raise
+            return []
+        finally:
+           if timeout > 0:
+               tout.cancel()
+
diff --git a/zmq/log/__init__.py b/zmq/log/__init__.py
new file mode 100644
index 0000000..e69de29
--- /dev/null
+++ b/zmq/log/__init__.py
diff --git a/zmq/log/handlers.py b/zmq/log/handlers.py
new file mode 100644
index 0000000..5ff21bf
--- /dev/null
+++ b/zmq/log/handlers.py
@@ -0,0 +1,146 @@
+"""pyzmq logging handlers.
+
+This mainly defines the PUBHandler object for publishing logging messages over
+a zmq.PUB socket.
+
+The PUBHandler can be used with the regular logging module, as in::
+
+    >>> import logging
+    >>> handler = PUBHandler('tcp://127.0.0.1:12345')
+    >>> handler.root_topic = 'foo'
+    >>> logger = logging.getLogger('foobar')
+    >>> logger.setLevel(logging.DEBUG)
+    >>> logger.addHandler(handler)
+
+After this point, all messages logged by ``logger`` will be published on the
+PUB socket.
+
+Code adapted from StarCluster:
+
+    http://github.com/jtriley/StarCluster/blob/master/starcluster/logger.py
+"""
+
+# Copyright (C) PyZMQ Developers
+# Distributed under the terms of the Modified BSD License.
+
+
+import logging
+from logging import INFO, DEBUG, WARN, ERROR, FATAL
+
+import zmq
+from zmq.utils.strtypes import bytes, unicode, cast_bytes
+
+
+TOPIC_DELIM="::" # delimiter for splitting topics on the receiving end.
+
+
+class PUBHandler(logging.Handler):
+    """A basic logging handler that emits log messages through a PUB socket.
+
+    Takes a PUB socket already bound to interfaces or an interface to bind to.
+
+    Example::
+
+        sock = context.socket(zmq.PUB)
+        sock.bind('inproc://log')
+        handler = PUBHandler(sock)
+
+    Or::
+
+        handler = PUBHandler('inproc://loc')
+
+    These are equivalent.
+
+    Log messages handled by this handler are broadcast with ZMQ topics
+    ``this.root_topic`` comes first, followed by the log level
+    (DEBUG,INFO,etc.), followed by any additional subtopics specified in the
+    message by: log.debug("subtopic.subsub::the real message")
+    """
+    root_topic=""
+    socket = None
+    
+    formatters = {
+        logging.DEBUG: logging.Formatter(
+        "%(levelname)s %(filename)s:%(lineno)d - %(message)s\n"),
+        logging.INFO: logging.Formatter("%(message)s\n"),
+        logging.WARN: logging.Formatter(
+        "%(levelname)s %(filename)s:%(lineno)d - %(message)s\n"),
+        logging.ERROR: logging.Formatter(
+        "%(levelname)s %(filename)s:%(lineno)d - %(message)s - %(exc_info)s\n"),
+        logging.CRITICAL: logging.Formatter(
+        "%(levelname)s %(filename)s:%(lineno)d - %(message)s\n")}
+    
+    def __init__(self, interface_or_socket, context=None):
+        logging.Handler.__init__(self)
+        if isinstance(interface_or_socket, zmq.Socket):
+            self.socket = interface_or_socket
+            self.ctx = self.socket.context
+        else:
+            self.ctx = context or zmq.Context()
+            self.socket = self.ctx.socket(zmq.PUB)
+            self.socket.bind(interface_or_socket)
+
+    def format(self,record):
+        """Format a record."""
+        return self.formatters[record.levelno].format(record)
+
+    def emit(self, record):
+        """Emit a log message on my socket."""
+        try:
+            topic, record.msg = record.msg.split(TOPIC_DELIM,1)
+        except Exception:
+            topic = ""
+        try:
+            bmsg = cast_bytes(self.format(record))
+        except Exception:
+            self.handleError(record)
+            return
+        
+        topic_list = []
+
+        if self.root_topic:
+            topic_list.append(self.root_topic)
+
+        topic_list.append(record.levelname)
+
+        if topic:
+            topic_list.append(topic)
+
+        btopic = b'.'.join(cast_bytes(t) for t in topic_list)
+
+        self.socket.send_multipart([btopic, bmsg])
+
+
+class TopicLogger(logging.Logger):
+    """A simple wrapper that takes an additional argument to log methods.
+
+    All the regular methods exist, but instead of one msg argument, two
+    arguments: topic, msg are passed.
+
+    That is::
+
+        logger.debug('msg')
+
+    Would become::
+
+        logger.debug('topic.sub', 'msg')
+    """
+    def log(self, level, topic, msg, *args, **kwargs):
+        """Log 'msg % args' with level and topic.
+
+        To pass exception information, use the keyword argument exc_info
+        with a True value::
+
+            logger.log(level, "zmq.fun", "We have a %s", 
+                    "mysterious problem", exc_info=1)
+        """
+        logging.Logger.log(self, level, '%s::%s'%(topic,msg), *args, **kwargs)
+
+# Generate the methods of TopicLogger, since they are just adding a
+# topic prefix to a message.
+for name in "debug warn warning error critical fatal".split():
+    meth = getattr(logging.Logger,name)
+    setattr(TopicLogger, name, 
+            lambda self, level, topic, msg, *args, **kwargs: 
+                meth(self, level, topic+TOPIC_DELIM+msg,*args, **kwargs))
+    
diff --git a/zmq/ssh/__init__.py b/zmq/ssh/__init__.py
new file mode 100644
index 0000000..57f0956
--- /dev/null
+++ b/zmq/ssh/__init__.py
@@ -0,0 +1 @@
+from zmq.ssh.tunnel import *
diff --git a/zmq/ssh/forward.py b/zmq/ssh/forward.py
new file mode 100644
index 0000000..2d61946
--- /dev/null
+++ b/zmq/ssh/forward.py
@@ -0,0 +1,91 @@
+#
+# This file is adapted from a paramiko demo, and thus licensed under LGPL 2.1.
+# Original Copyright (C) 2003-2007  Robey Pointer <robeypointer@gmail.com>
+# Edits Copyright (C) 2010 The IPython Team
+#
+# Paramiko is free software; you can redistribute it and/or modify it under the
+# terms of the GNU Lesser General Public License as published by the Free
+# Software Foundation; either version 2.1 of the License, or (at your option)
+# any later version.
+#
+# Paramiko is distrubuted in the hope that it will be useful, but WITHOUT ANY
+# WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
+# A PARTICULAR PURPOSE.  See the GNU Lesser General Public License for more
+# details.
+#
+# You should have received a copy of the GNU Lesser General Public License
+# along with Paramiko; if not, write to the Free Software Foundation, Inc.,
+# 51 Franklin Street, Fifth Floor, Boston, MA  02111-1301  USA.
+
+"""
+Sample script showing how to do local port forwarding over paramiko.
+
+This script connects to the requested SSH server and sets up local port
+forwarding (the openssh -L option) from a local port through a tunneled
+connection to a destination reachable from the SSH server machine.
+"""
+
+from __future__ import print_function
+
+import logging
+import select
+try:  # Python 3
+    import socketserver
+except ImportError:  # Python 2
+    import SocketServer as socketserver
+
+logger = logging.getLogger('ssh')
+
+class ForwardServer (socketserver.ThreadingTCPServer):
+    daemon_threads = True
+    allow_reuse_address = True
+    
+
+class Handler (socketserver.BaseRequestHandler):
+
+    def handle(self):
+        try:
+            chan = self.ssh_transport.open_channel('direct-tcpip',
+                                                   (self.chain_host, self.chain_port),
+                                                   self.request.getpeername())
+        except Exception as e:
+            logger.debug('Incoming request to %s:%d failed: %s' % (self.chain_host,
+                                                              self.chain_port,
+                                                              repr(e)))
+            return
+        if chan is None:
+            logger.debug('Incoming request to %s:%d was rejected by the SSH server.' %
+                    (self.chain_host, self.chain_port))
+            return
+
+        logger.debug('Connected!  Tunnel open %r -> %r -> %r' % (self.request.getpeername(),
+                                                            chan.getpeername(), (self.chain_host, self.chain_port)))
+        while True:
+            r, w, x = select.select([self.request, chan], [], [])
+            if self.request in r:
+                data = self.request.recv(1024)
+                if len(data) == 0:
+                    break
+                chan.send(data)
+            if chan in r:
+                data = chan.recv(1024)
+                if len(data) == 0:
+                    break
+                self.request.send(data)
+        chan.close()
+        self.request.close()
+        logger.debug('Tunnel closed ')
+
+
+def forward_tunnel(local_port, remote_host, remote_port, transport):
+    # this is a little convoluted, but lets me configure things for the Handler
+    # object.  (SocketServer doesn't give Handlers any way to access the outer
+    # server normally.)
+    class SubHander (Handler):
+        chain_host = remote_host
+        chain_port = remote_port
+        ssh_transport = transport
+    ForwardServer(('127.0.0.1', local_port), SubHander).serve_forever()
+
+
+__all__ = ['forward_tunnel']
diff --git a/zmq/ssh/tunnel.py b/zmq/ssh/tunnel.py
new file mode 100644
index 0000000..6400352
--- /dev/null
+++ b/zmq/ssh/tunnel.py
@@ -0,0 +1,368 @@
+"""Basic ssh tunnel utilities, and convenience functions for tunneling
+zeromq connections.
+"""
+
+# Copyright (C) 2010-2011  IPython Development Team
+# Copyright (C) 2011- PyZMQ Developers
+#
+# Redistributed from IPython under the terms of the BSD License.
+
+
+from __future__ import print_function
+
+import atexit
+import os
+import signal
+import socket
+import sys
+import warnings
+from getpass import getpass, getuser
+from multiprocessing import Process
+
+try:
+    with warnings.catch_warnings():
+        warnings.simplefilter('ignore', DeprecationWarning)
+        import paramiko
+except ImportError:
+    paramiko = None
+else:
+    from .forward import forward_tunnel
+
+
+try:
+    import pexpect
+except ImportError:
+    pexpect = None
+
+
+_random_ports = set()
+
+def select_random_ports(n):
+    """Selects and return n random ports that are available."""
+    ports = []
+    for i in range(n):
+        sock = socket.socket()
+        sock.bind(('', 0))
+        while sock.getsockname()[1] in _random_ports:
+            sock.close()
+            sock = socket.socket()
+            sock.bind(('', 0))
+        ports.append(sock)
+    for i, sock in enumerate(ports):
+        port = sock.getsockname()[1]
+        sock.close()
+        ports[i] = port
+        _random_ports.add(port)
+    return ports
+
+
+#-----------------------------------------------------------------------------
+# Check for passwordless login
+#-----------------------------------------------------------------------------
+
+def try_passwordless_ssh(server, keyfile, paramiko=None):
+    """Attempt to make an ssh connection without a password.
+    This is mainly used for requiring password input only once
+    when many tunnels may be connected to the same server.
+    
+    If paramiko is None, the default for the platform is chosen.
+    """
+    if paramiko is None:
+        paramiko = sys.platform == 'win32'
+    if not paramiko:
+        f = _try_passwordless_openssh
+    else:
+        f = _try_passwordless_paramiko
+    return f(server, keyfile)
+
+def _try_passwordless_openssh(server, keyfile):
+    """Try passwordless login with shell ssh command."""
+    if pexpect is None:
+        raise ImportError("pexpect unavailable, use paramiko")
+    cmd = 'ssh -f '+ server
+    if keyfile:
+        cmd += ' -i ' + keyfile
+    cmd += ' exit'
+    
+    # pop SSH_ASKPASS from env
+    env = os.environ.copy()
+    env.pop('SSH_ASKPASS', None)
+    
+    p = pexpect.spawn(cmd, env=env)
+    while True:
+        try:
+            p.expect('[Pp]assword:', timeout=.1)
+        except pexpect.TIMEOUT:
+            continue
+        except pexpect.EOF:
+            return True
+        else:
+            return False
+
+def _try_passwordless_paramiko(server, keyfile):
+    """Try passwordless login with paramiko."""
+    if paramiko is None:
+        msg = "Paramiko unavaliable, "
+        if sys.platform == 'win32':
+            msg += "Paramiko is required for ssh tunneled connections on Windows."
+        else:
+            msg += "use OpenSSH."
+        raise ImportError(msg)
+    username, server, port = _split_server(server)
+    client = paramiko.SSHClient()
+    client.load_system_host_keys()
+    client.set_missing_host_key_policy(paramiko.WarningPolicy())
+    try:
+        client.connect(server, port, username=username, key_filename=keyfile,
+               look_for_keys=True)
+    except paramiko.AuthenticationException:
+        return False
+    else:
+        client.close()
+        return True
+
+
+def tunnel_connection(socket, addr, server, keyfile=None, password=None, paramiko=None, timeout=60):
+    """Connect a socket to an address via an ssh tunnel.
+    
+    This is a wrapper for socket.connect(addr), when addr is not accessible
+    from the local machine.  It simply creates an ssh tunnel using the remaining args,
+    and calls socket.connect('tcp://localhost:lport') where lport is the randomly
+    selected local port of the tunnel.
+    
+    """
+    new_url, tunnel = open_tunnel(addr, server, keyfile=keyfile, password=password, paramiko=paramiko, timeout=timeout)
+    socket.connect(new_url)
+    return tunnel
+
+
+def open_tunnel(addr, server, keyfile=None, password=None, paramiko=None, timeout=60):
+    """Open a tunneled connection from a 0MQ url.
+    
+    For use inside tunnel_connection.
+    
+    Returns
+    -------
+    
+    (url, tunnel) : (str, object)
+        The 0MQ url that has been forwarded, and the tunnel object
+    """
+    
+    lport = select_random_ports(1)[0]
+    transport, addr = addr.split('://')
+    ip,rport = addr.split(':')
+    rport = int(rport)
+    if paramiko is None:
+        paramiko = sys.platform == 'win32'
+    if paramiko:
+        tunnelf = paramiko_tunnel
+    else:
+        tunnelf = openssh_tunnel
+    
+    tunnel = tunnelf(lport, rport, server, remoteip=ip, keyfile=keyfile, password=password, timeout=timeout)
+    return 'tcp://127.0.0.1:%i'%lport, tunnel
+
+def openssh_tunnel(lport, rport, server, remoteip='127.0.0.1', keyfile=None, password=None, timeout=60):
+    """Create an ssh tunnel using command-line ssh that connects port lport
+    on this machine to localhost:rport on server.  The tunnel
+    will automatically close when not in use, remaining open
+    for a minimum of timeout seconds for an initial connection.
+    
+    This creates a tunnel redirecting `localhost:lport` to `remoteip:rport`,
+    as seen from `server`.
+    
+    keyfile and password may be specified, but ssh config is checked for defaults.
+    
+    Parameters
+    ----------
+    
+    lport : int
+        local port for connecting to the tunnel from this machine.
+    rport : int
+        port on the remote machine to connect to.
+    server : str
+        The ssh server to connect to. The full ssh server string will be parsed.
+        user@server:port
+    remoteip : str [Default: 127.0.0.1]
+        The remote ip, specifying the destination of the tunnel.
+        Default is localhost, which means that the tunnel would redirect
+        localhost:lport on this machine to localhost:rport on the *server*.
+        
+    keyfile : str; path to public key file
+        This specifies a key to be used in ssh login, default None.
+        Regular default ssh keys will be used without specifying this argument.
+    password : str; 
+        Your ssh password to the ssh server. Note that if this is left None,
+        you will be prompted for it if passwordless key based login is unavailable.
+    timeout : int [default: 60]
+        The time (in seconds) after which no activity will result in the tunnel
+        closing.  This prevents orphaned tunnels from running forever.
+    """
+    if pexpect is None:
+        raise ImportError("pexpect unavailable, use paramiko_tunnel")
+    ssh="ssh "
+    if keyfile:
+        ssh += "-i " + keyfile
+    
+    if ':' in server:
+        server, port = server.split(':')
+        ssh += " -p %s" % port
+    
+    cmd = "%s -O check %s" % (ssh, server)
+    (output, exitstatus) = pexpect.run(cmd, withexitstatus=True)
+    if not exitstatus:
+        pid = int(output[output.find("(pid=")+5:output.find(")")]) 
+        cmd = "%s -O forward -L 127.0.0.1:%i:%s:%i %s" % (
+            ssh, lport, remoteip, rport, server)
+        (output, exitstatus) = pexpect.run(cmd, withexitstatus=True)
+        if not exitstatus:
+            atexit.register(_stop_tunnel, cmd.replace("-O forward", "-O cancel", 1))
+            return pid
+    cmd = "%s -f -S none -L 127.0.0.1:%i:%s:%i %s sleep %i" % (
+        ssh, lport, remoteip, rport, server, timeout)
+    
+    # pop SSH_ASKPASS from env
+    env = os.environ.copy()
+    env.pop('SSH_ASKPASS', None)
+    
+    tunnel = pexpect.spawn(cmd, env=env)
+    failed = False
+    while True:
+        try:
+            tunnel.expect('[Pp]assword:', timeout=.1)
+        except pexpect.TIMEOUT:
+            continue
+        except pexpect.EOF:
+            if tunnel.exitstatus:
+                print(tunnel.exitstatus)
+                print(tunnel.before)
+                print(tunnel.after)
+                raise RuntimeError("tunnel '%s' failed to start"%(cmd))
+            else:
+                return tunnel.pid
+        else:
+            if failed:
+                print("Password rejected, try again")
+                password=None
+            if password is None:
+                password = getpass("%s's password: "%(server))
+            tunnel.sendline(password)
+            failed = True
+    
+def _stop_tunnel(cmd):
+    pexpect.run(cmd)
+
+def _split_server(server):
+    if '@' in server:
+        username,server = server.split('@', 1)
+    else:
+        username = getuser()
+    if ':' in server:
+        server, port = server.split(':')
+        port = int(port)
+    else:
+        port = 22
+    return username, server, port
+
+def paramiko_tunnel(lport, rport, server, remoteip='127.0.0.1', keyfile=None, password=None, timeout=60):
+    """launch a tunner with paramiko in a subprocess. This should only be used
+    when shell ssh is unavailable (e.g. Windows).
+    
+    This creates a tunnel redirecting `localhost:lport` to `remoteip:rport`,
+    as seen from `server`.
+    
+    If you are familiar with ssh tunnels, this creates the tunnel:
+    
+    ssh server -L localhost:lport:remoteip:rport
+    
+    keyfile and password may be specified, but ssh config is checked for defaults.
+    
+    
+    Parameters
+    ----------
+    
+    lport : int
+        local port for connecting to the tunnel from this machine.
+    rport : int
+        port on the remote machine to connect to.
+    server : str
+        The ssh server to connect to. The full ssh server string will be parsed.
+        user@server:port
+    remoteip : str [Default: 127.0.0.1]
+        The remote ip, specifying the destination of the tunnel.
+        Default is localhost, which means that the tunnel would redirect
+        localhost:lport on this machine to localhost:rport on the *server*.
+        
+    keyfile : str; path to public key file
+        This specifies a key to be used in ssh login, default None.
+        Regular default ssh keys will be used without specifying this argument.
+    password : str; 
+        Your ssh password to the ssh server. Note that if this is left None,
+        you will be prompted for it if passwordless key based login is unavailable.
+    timeout : int [default: 60]
+        The time (in seconds) after which no activity will result in the tunnel
+        closing.  This prevents orphaned tunnels from running forever.
+    
+    """
+    if paramiko is None:
+        raise ImportError("Paramiko not available")
+    
+    if password is None:
+        if not _try_passwordless_paramiko(server, keyfile):
+            password = getpass("%s's password: "%(server))
+
+    p = Process(target=_paramiko_tunnel, 
+            args=(lport, rport, server, remoteip), 
+            kwargs=dict(keyfile=keyfile, password=password))
+    p.daemon=False
+    p.start()
+    atexit.register(_shutdown_process, p)
+    return p
+    
+def _shutdown_process(p):
+    if p.is_alive():
+        p.terminate()
+
+def _paramiko_tunnel(lport, rport, server, remoteip, keyfile=None, password=None):
+    """Function for actually starting a paramiko tunnel, to be passed
+    to multiprocessing.Process(target=this), and not called directly.
+    """
+    username, server, port = _split_server(server)
+    client = paramiko.SSHClient()
+    client.load_system_host_keys()
+    client.set_missing_host_key_policy(paramiko.WarningPolicy())
+
+    try:
+        client.connect(server, port, username=username, key_filename=keyfile,
+                       look_for_keys=True, password=password)
+#    except paramiko.AuthenticationException:
+#        if password is None:
+#            password = getpass("%s@%s's password: "%(username, server))
+#            client.connect(server, port, username=username, password=password)
+#        else:
+#            raise
+    except Exception as e:
+        print('*** Failed to connect to %s:%d: %r' % (server, port, e))
+        sys.exit(1)
+
+    # Don't let SIGINT kill the tunnel subprocess
+    signal.signal(signal.SIGINT, signal.SIG_IGN)
+
+    try:
+        forward_tunnel(lport, remoteip, rport, client.get_transport())
+    except KeyboardInterrupt:
+        print('SIGINT: Port forwarding stopped cleanly')
+        sys.exit(0)
+    except Exception as e:
+        print("Port forwarding stopped uncleanly: %s"%e)
+        sys.exit(255)
+
+if sys.platform == 'win32':
+    ssh_tunnel = paramiko_tunnel
+else:
+    ssh_tunnel = openssh_tunnel
+
+    
+__all__ = ['tunnel_connection', 'ssh_tunnel', 'openssh_tunnel', 'paramiko_tunnel', 'try_passwordless_ssh']
+
+
diff --git a/zmq/sugar/__init__.py b/zmq/sugar/__init__.py
new file mode 100644
index 0000000..d0510a4
--- /dev/null
+++ b/zmq/sugar/__init__.py
@@ -0,0 +1,27 @@
+"""pure-Python sugar wrappers for core 0MQ objects."""
+
+# Copyright (C) PyZMQ Developers
+# Distributed under the terms of the Modified BSD License.
+
+
+from zmq.sugar import (
+    constants, context, frame, poll, socket, tracker, version
+)
+from zmq import error
+
+__all__ = ['constants']
+for submod in (
+    constants, context, error, frame, poll, socket, tracker, version
+):
+    __all__.extend(submod.__all__)
+
+from zmq.error import *
+from zmq.sugar.context import *
+from zmq.sugar.tracker import *
+from zmq.sugar.socket import *
+from zmq.sugar.constants import *
+from zmq.sugar.frame import *
+from zmq.sugar.poll import *
+# from zmq.sugar.stopwatch import *
+# from zmq.sugar._device import *
+from zmq.sugar.version import *
diff --git a/zmq/sugar/attrsettr.py b/zmq/sugar/attrsettr.py
new file mode 100644
index 0000000..4bbd36d
--- /dev/null
+++ b/zmq/sugar/attrsettr.py
@@ -0,0 +1,52 @@
+# coding: utf-8
+"""Mixin for mapping set/getattr to self.set/get"""
+
+# Copyright (C) PyZMQ Developers
+# Distributed under the terms of the Modified BSD License.
+
+
+from . import constants
+
+class AttributeSetter(object):
+    
+    def __setattr__(self, key, value):
+        """set zmq options by attribute"""
+        
+        # regular setattr only allowed for class-defined attributes
+        for obj in [self] + self.__class__.mro():
+            if key in obj.__dict__:
+                object.__setattr__(self, key, value)
+                return
+        
+        upper_key = key.upper()
+        try:
+            opt = getattr(constants, upper_key)
+        except AttributeError:
+            raise AttributeError("%s has no such option: %s" % (
+                self.__class__.__name__, upper_key)
+            )
+        else:
+            self._set_attr_opt(upper_key, opt, value)
+    
+    def _set_attr_opt(self, name, opt, value):
+        """override if setattr should do something other than call self.set"""
+        self.set(opt, value)
+    
+    def __getattr__(self, key):
+        """get zmq options by attribute"""
+        upper_key = key.upper()
+        try:
+            opt = getattr(constants, upper_key)
+        except AttributeError:
+            raise AttributeError("%s has no such option: %s" % (
+                self.__class__.__name__, upper_key)
+            )
+        else:
+            return self._get_attr_opt(upper_key, opt)
+
+    def _get_attr_opt(self, name, opt):
+        """override if getattr should do something other than call self.get"""
+        return self.get(opt)
+    
+
+__all__ = ['AttributeSetter']
diff --git a/zmq/sugar/constants.py b/zmq/sugar/constants.py
new file mode 100644
index 0000000..8828117
--- /dev/null
+++ b/zmq/sugar/constants.py
@@ -0,0 +1,98 @@
+"""0MQ Constants."""
+
+# Copyright (c) PyZMQ Developers.
+# Distributed under the terms of the Modified BSD License.
+
+from zmq.backend import constants
+from zmq.utils.constant_names import (
+    base_names,
+    switched_sockopt_names,
+    int_sockopt_names,
+    int64_sockopt_names,
+    bytes_sockopt_names,
+    fd_sockopt_names,
+    ctx_opt_names,
+    msg_opt_names,
+)
+
+#-----------------------------------------------------------------------------
+# Python module level constants
+#-----------------------------------------------------------------------------
+
+__all__ = [
+    'int_sockopts',
+    'int64_sockopts',
+    'bytes_sockopts',
+    'ctx_opts',
+    'ctx_opt_names',
+    ]
+
+int_sockopts    = set()
+int64_sockopts  = set()
+bytes_sockopts  = set()
+fd_sockopts     = set()
+ctx_opts        = set()
+msg_opts        = set()
+
+
+if constants.VERSION < 30000:
+    int64_sockopt_names.extend(switched_sockopt_names)
+else:
+    int_sockopt_names.extend(switched_sockopt_names)
+    
+_UNDEFINED = -9999
+
+def _add_constant(name, container=None):
+    """add a constant to be defined
+    
+    optionally add it to one of the sets for use in get/setopt checkers
+    """
+    c = getattr(constants, name, _UNDEFINED)
+    if c == _UNDEFINED:
+        return
+    globals()[name] = c
+    __all__.append(name)
+    if container is not None:
+        container.add(c)
+    return c
+    
+for name in base_names:
+    _add_constant(name)
+
+for name in int_sockopt_names:
+    _add_constant(name, int_sockopts)
+
+for name in int64_sockopt_names:
+    _add_constant(name, int64_sockopts)
+
+for name in bytes_sockopt_names:
+    _add_constant(name, bytes_sockopts)
+
+for name in fd_sockopt_names:
+    _add_constant(name, fd_sockopts)
+
+for name in ctx_opt_names:
+    _add_constant(name, ctx_opts)
+
+for name in msg_opt_names:
+    _add_constant(name, msg_opts)
+
+# ensure some aliases are always defined
+aliases = [
+    ('DONTWAIT', 'NOBLOCK'),
+    ('XREQ', 'DEALER'),
+    ('XREP', 'ROUTER'),
+]
+for group in aliases:
+    undefined = set()
+    found = None
+    for name in group:
+        value = getattr(constants, name, -1)
+        if value != -1:
+            found = value
+        else:
+            undefined.add(name)
+    if found is not None:
+        for name in undefined:
+            globals()[name] = found
+            __all__.append(name)
diff --git a/zmq/sugar/context.py b/zmq/sugar/context.py
new file mode 100644
index 0000000..86a9c5d
--- /dev/null
+++ b/zmq/sugar/context.py
@@ -0,0 +1,192 @@
+# coding: utf-8
+"""Python bindings for 0MQ."""
+
+# Copyright (C) PyZMQ Developers
+# Distributed under the terms of the Modified BSD License.
+
+import atexit
+import weakref
+
+from zmq.backend import Context as ContextBase
+from . import constants
+from .attrsettr import AttributeSetter
+from .constants import ENOTSUP, ctx_opt_names
+from .socket import Socket
+from zmq.error import ZMQError
+
+from zmq.utils.interop import cast_int_addr
+
+
+class Context(ContextBase, AttributeSetter):
+    """Create a zmq Context
+    
+    A zmq Context creates sockets via its ``ctx.socket`` method.
+    """
+    sockopts = None
+    _instance = None
+    _shadow = False
+    _exiting = False
+    
+    def __init__(self, io_threads=1, **kwargs):
+        super(Context, self).__init__(io_threads=io_threads, **kwargs)
+        if kwargs.get('shadow', False):
+            self._shadow = True
+        else:
+            self._shadow = False
+        self.sockopts = {}
+        
+        self._exiting = False
+        if not self._shadow:
+            ctx_ref = weakref.ref(self)
+            def _notify_atexit():
+                ctx = ctx_ref()
+                if ctx is not None:
+                    ctx._exiting = True
+            atexit.register(_notify_atexit)
+    
+    def __del__(self):
+        """deleting a Context should terminate it, without trying non-threadsafe destroy"""
+        if not self._shadow and not self._exiting:
+            self.term()
+    
+    def __enter__(self):
+        return self
+    
+    def __exit__(self, *args, **kwargs):
+        self.term()
+    
+    @classmethod
+    def shadow(cls, address):
+        """Shadow an existing libzmq context
+        
+        address is the integer address of the libzmq context
+        or an FFI pointer to it.
+        
+        .. versionadded:: 14.1
+        """
+        address = cast_int_addr(address)
+        return cls(shadow=address)
+    
+    @classmethod
+    def shadow_pyczmq(cls, ctx):
+        """Shadow an existing pyczmq context
+        
+        ctx is the FFI `zctx_t *` pointer
+        
+        .. versionadded:: 14.1
+        """
+        from pyczmq import zctx
+        
+        underlying = zctx.underlying(ctx)
+        address = cast_int_addr(underlying)
+        return cls(shadow=address)
+
+    # static method copied from tornado IOLoop.instance
+    @classmethod
+    def instance(cls, io_threads=1):
+        """Returns a global Context instance.
+
+        Most single-threaded applications have a single, global Context.
+        Use this method instead of passing around Context instances
+        throughout your code.
+
+        A common pattern for classes that depend on Contexts is to use
+        a default argument to enable programs with multiple Contexts
+        but not require the argument for simpler applications:
+
+            class MyClass(object):
+                def __init__(self, context=None):
+                    self.context = context or Context.instance()
+        """
+        if cls._instance is None or cls._instance.closed:
+            cls._instance = cls(io_threads=io_threads)
+        return cls._instance
+    
+    #-------------------------------------------------------------------------
+    # Hooks for ctxopt completion
+    #-------------------------------------------------------------------------
+    
+    def __dir__(self):
+        keys = dir(self.__class__)
+
+        for collection in (
+            ctx_opt_names,
+        ):
+            keys.extend(collection)
+        return keys
+
+    #-------------------------------------------------------------------------
+    # Creating Sockets
+    #-------------------------------------------------------------------------
+
+    @property
+    def _socket_class(self):
+        return Socket
+    
+    def socket(self, socket_type):
+        """Create a Socket associated with this Context.
+
+        Parameters
+        ----------
+        socket_type : int
+            The socket type, which can be any of the 0MQ socket types:
+            REQ, REP, PUB, SUB, PAIR, DEALER, ROUTER, PULL, PUSH, etc.
+        """
+        if self.closed:
+            raise ZMQError(ENOTSUP)
+        s = self._socket_class(self, socket_type)
+        for opt, value in self.sockopts.items():
+            try:
+                s.setsockopt(opt, value)
+            except ZMQError:
+                # ignore ZMQErrors, which are likely for socket options
+                # that do not apply to a particular socket type, e.g.
+                # SUBSCRIBE for non-SUB sockets.
+                pass
+        return s
+    
+    def setsockopt(self, opt, value):
+        """set default socket options for new sockets created by this Context
+        
+        .. versionadded:: 13.0
+        """
+        self.sockopts[opt] = value
+    
+    def getsockopt(self, opt):
+        """get default socket options for new sockets created by this Context
+        
+        .. versionadded:: 13.0
+        """
+        return self.sockopts[opt]
+    
+    def _set_attr_opt(self, name, opt, value):
+        """set default sockopts as attributes"""
+        if name in constants.ctx_opt_names:
+            return self.set(opt, value)
+        else:
+            self.sockopts[opt] = value
+    
+    def _get_attr_opt(self, name, opt):
+        """get default sockopts as attributes"""
+        if name in constants.ctx_opt_names:
+            return self.get(opt)
+        else:
+            if opt not in self.sockopts:
+                raise AttributeError(name)
+            else:
+                return self.sockopts[opt]
+    
+    def __delattr__(self, key):
+        """delete default sockopts as attributes"""
+        key = key.upper()
+        try:
+            opt = getattr(constants, key)
+        except AttributeError:
+            raise AttributeError("no such socket option: %s" % key)
+        else:
+            if opt not in self.sockopts:
+                raise AttributeError(key)
+            else:
+                del self.sockopts[opt]
+
+__all__ = ['Context']
diff --git a/zmq/sugar/frame.py b/zmq/sugar/frame.py
new file mode 100644
index 0000000..9f556c8
--- /dev/null
+++ b/zmq/sugar/frame.py
@@ -0,0 +1,19 @@
+# coding: utf-8
+"""0MQ Frame pure Python methods."""
+
+# Copyright (C) PyZMQ Developers
+# Distributed under the terms of the Modified BSD License.
+
+
+from .attrsettr import AttributeSetter
+from zmq.backend import Frame as FrameBase
+
+
+class Frame(FrameBase, AttributeSetter):
+    def __getitem__(self, key):
+        # map Frame['User-Id'] to Frame.get('User-Id')
+        return self.get(key)
+
+# keep deprecated alias
+Message = Frame
+__all__ = ['Frame', 'Message']
\ No newline at end of file
diff --git a/zmq/sugar/poll.py b/zmq/sugar/poll.py
new file mode 100644
index 0000000..c7b1d1b
--- /dev/null
+++ b/zmq/sugar/poll.py
@@ -0,0 +1,161 @@
+"""0MQ polling related functions and classes."""
+
+# Copyright (C) PyZMQ Developers
+# Distributed under the terms of the Modified BSD License.
+
+
+import zmq
+from zmq.backend import zmq_poll
+from .constants import POLLIN, POLLOUT, POLLERR
+
+#-----------------------------------------------------------------------------
+# Polling related methods
+#-----------------------------------------------------------------------------
+
+
+class Poller(object):
+    """A stateful poll interface that mirrors Python's built-in poll."""
+    sockets = None
+    _map = {}
+
+    def __init__(self):
+        self.sockets = []
+        self._map = {}
+    
+    def __contains__(self, socket):
+        return socket in self._map
+
+    def register(self, socket, flags=POLLIN|POLLOUT):
+        """p.register(socket, flags=POLLIN|POLLOUT)
+
+        Register a 0MQ socket or native fd for I/O monitoring.
+        
+        register(s,0) is equivalent to unregister(s).
+
+        Parameters
+        ----------
+        socket : zmq.Socket or native socket
+            A zmq.Socket or any Python object having a ``fileno()`` 
+            method that returns a valid file descriptor.
+        flags : int
+            The events to watch for.  Can be POLLIN, POLLOUT or POLLIN|POLLOUT.
+            If `flags=0`, socket will be unregistered.
+        """
+        if flags:
+            if socket in self._map:
+                idx = self._map[socket]
+                self.sockets[idx] = (socket, flags)
+            else:
+                idx = len(self.sockets)
+                self.sockets.append((socket, flags))
+                self._map[socket] = idx
+        elif socket in self._map:
+            # uregister sockets registered with no events
+            self.unregister(socket)
+        else:
+            # ignore new sockets with no events
+            pass
+
+    def modify(self, socket, flags=POLLIN|POLLOUT):
+        """Modify the flags for an already registered 0MQ socket or native fd."""
+        self.register(socket, flags)
+
+    def unregister(self, socket):
+        """Remove a 0MQ socket or native fd for I/O monitoring.
+
+        Parameters
+        ----------
+        socket : Socket
+            The socket instance to stop polling.
+        """
+        idx = self._map.pop(socket)
+        self.sockets.pop(idx)
+        # shift indices after deletion
+        for socket, flags in self.sockets[idx:]:
+            self._map[socket] -= 1
+
+    def poll(self, timeout=None):
+        """Poll the registered 0MQ or native fds for I/O.
+
+        Parameters
+        ----------
+        timeout : float, int
+            The timeout in milliseconds. If None, no `timeout` (infinite). This
+            is in milliseconds to be compatible with ``select.poll()``. The
+            underlying zmq_poll uses microseconds and we convert to that in
+            this function.
+        
+        Returns
+        -------
+        events : list of tuples
+            The list of events that are ready to be processed.
+            This is a list of tuples of the form ``(socket, event)``, where the 0MQ Socket
+            or integer fd is the first element, and the poll event mask (POLLIN, POLLOUT) is the second.
+            It is common to call ``events = dict(poller.poll())``,
+            which turns the list of tuples into a mapping of ``socket : event``.
+        """
+        if timeout is None or timeout < 0:
+            timeout = -1
+        elif isinstance(timeout, float):
+            timeout = int(timeout)
+        return zmq_poll(self.sockets, timeout=timeout)
+
+
+def select(rlist, wlist, xlist, timeout=None):
+    """select(rlist, wlist, xlist, timeout=None) -> (rlist, wlist, xlist)
+
+    Return the result of poll as a lists of sockets ready for r/w/exception.
+
+    This has the same interface as Python's built-in ``select.select()`` function.
+
+    Parameters
+    ----------
+    timeout : float, int, optional
+        The timeout in seconds. If None, no timeout (infinite). This is in seconds to be
+        compatible with ``select.select()``. The underlying zmq_poll uses microseconds
+        and we convert to that in this function.
+    rlist : list of sockets/FDs
+        sockets/FDs to be polled for read events
+    wlist : list of sockets/FDs
+        sockets/FDs to be polled for write events
+    xlist : list of sockets/FDs
+        sockets/FDs to be polled for error events
+    
+    Returns
+    -------
+    (rlist, wlist, xlist) : tuple of lists of sockets (length 3)
+        Lists correspond to sockets available for read/write/error events respectively.
+    """
+    if timeout is None:
+        timeout = -1
+    # Convert from sec -> us for zmq_poll.
+    # zmq_poll accepts 3.x style timeout in ms
+    timeout = int(timeout*1000.0)
+    if timeout < 0:
+        timeout = -1
+    sockets = []
+    for s in set(rlist + wlist + xlist):
+        flags = 0
+        if s in rlist:
+            flags |= POLLIN
+        if s in wlist:
+            flags |= POLLOUT
+        if s in xlist:
+            flags |= POLLERR
+        sockets.append((s, flags))
+    return_sockets = zmq_poll(sockets, timeout)
+    rlist, wlist, xlist = [], [], []
+    for s, flags in return_sockets:
+        if flags & POLLIN:
+            rlist.append(s)
+        if flags & POLLOUT:
+            wlist.append(s)
+        if flags & POLLERR:
+            xlist.append(s)
+    return rlist, wlist, xlist
+
+#-----------------------------------------------------------------------------
+# Symbols to export
+#-----------------------------------------------------------------------------
+
+__all__ = [ 'Poller', 'select' ]
diff --git a/zmq/sugar/socket.py b/zmq/sugar/socket.py
new file mode 100644
index 0000000..ab56deb
--- /dev/null
+++ b/zmq/sugar/socket.py
@@ -0,0 +1,491 @@
+# coding: utf-8
+"""0MQ Socket pure Python methods."""
+
+# Copyright (C) PyZMQ Developers
+# Distributed under the terms of the Modified BSD License.
+
+
+import codecs
+import random
+import warnings
+
+import zmq
+from zmq.backend import Socket as SocketBase
+from .poll import Poller
+from . import constants
+from .attrsettr import AttributeSetter
+from zmq.error import ZMQError, ZMQBindError
+from zmq.utils import jsonapi
+from zmq.utils.strtypes import bytes,unicode,basestring
+from zmq.utils.interop import cast_int_addr
+
+from .constants import (
+    SNDMORE, ENOTSUP, POLLIN,
+    int64_sockopt_names,
+    int_sockopt_names,
+    bytes_sockopt_names,
+    fd_sockopt_names,
+)
+try:
+    import cPickle
+    pickle = cPickle
+except:
+    cPickle = None
+    import pickle
+
+
+class Socket(SocketBase, AttributeSetter):
+    """The ZMQ socket object
+    
+    To create a Socket, first create a Context::
+    
+        ctx = zmq.Context.instance()
+    
+    then call ``ctx.socket(socket_type)``::
+    
+        s = ctx.socket(zmq.ROUTER)
+    
+    """
+    _shadow = False
+    
+    def __del__(self):
+        if not self._shadow:
+            self.close()
+    
+    # socket as context manager:
+    def __enter__(self):
+        """Sockets are context managers
+        
+        .. versionadded:: 14.4
+        """
+        return self
+    
+    def __exit__(self, *args, **kwargs):
+        self.close()
+    
+    #-------------------------------------------------------------------------
+    # Socket creation
+    #-------------------------------------------------------------------------
+    
+    @classmethod
+    def shadow(cls, address):
+        """Shadow an existing libzmq socket
+        
+        address is the integer address of the libzmq socket
+        or an FFI pointer to it.
+        
+        .. versionadded:: 14.1
+        """
+        address = cast_int_addr(address)
+        return cls(shadow=address)
+    
+    #-------------------------------------------------------------------------
+    # Deprecated aliases
+    #-------------------------------------------------------------------------
+    
+    @property
+    def socket_type(self):
+        warnings.warn("Socket.socket_type is deprecated, use Socket.type",
+            DeprecationWarning
+        )
+        return self.type
+    
+    #-------------------------------------------------------------------------
+    # Hooks for sockopt completion
+    #-------------------------------------------------------------------------
+    
+    def __dir__(self):
+        keys = dir(self.__class__)
+        for collection in (
+            bytes_sockopt_names,
+            int_sockopt_names,
+            int64_sockopt_names,
+            fd_sockopt_names,
+        ):
+            keys.extend(collection)
+        return keys
+    
+    #-------------------------------------------------------------------------
+    # Getting/Setting options
+    #-------------------------------------------------------------------------
+    setsockopt = SocketBase.set
+    getsockopt = SocketBase.get
+    
+    def set_string(self, option, optval, encoding='utf-8'):
+        """set socket options with a unicode object
+        
+        This is simply a wrapper for setsockopt to protect from encoding ambiguity.
+
+        See the 0MQ documentation for details on specific options.
+        
+        Parameters
+        ----------
+        option : int
+            The name of the option to set. Can be any of: SUBSCRIBE, 
+            UNSUBSCRIBE, IDENTITY
+        optval : unicode string (unicode on py2, str on py3)
+            The value of the option to set.
+        encoding : str
+            The encoding to be used, default is utf8
+        """
+        if not isinstance(optval, unicode):
+            raise TypeError("unicode strings only")
+        return self.set(option, optval.encode(encoding))
+    
+    setsockopt_unicode = setsockopt_string = set_string
+    
+    def get_string(self, option, encoding='utf-8'):
+        """get the value of a socket option
+
+        See the 0MQ documentation for details on specific options.
+
+        Parameters
+        ----------
+        option : int
+            The option to retrieve.
+
+        Returns
+        -------
+        optval : unicode string (unicode on py2, str on py3)
+            The value of the option as a unicode string.
+        """
+    
+        if option not in constants.bytes_sockopts:
+            raise TypeError("option %i will not return a string to be decoded"%option)
+        return self.getsockopt(option).decode(encoding)
+    
+    getsockopt_unicode = getsockopt_string = get_string
+    
+    def bind_to_random_port(self, addr, min_port=49152, max_port=65536, max_tries=100):
+        """bind this socket to a random port in a range
+
+        Parameters
+        ----------
+        addr : str
+            The address string without the port to pass to ``Socket.bind()``.
+        min_port : int, optional
+            The minimum port in the range of ports to try (inclusive).
+        max_port : int, optional
+            The maximum port in the range of ports to try (exclusive).
+        max_tries : int, optional
+            The maximum number of bind attempts to make.
+
+        Returns
+        -------
+        port : int
+            The port the socket was bound to.
+    
+        Raises
+        ------
+        ZMQBindError
+            if `max_tries` reached before successful bind
+        """
+        for i in range(max_tries):
+            try:
+                port = random.randrange(min_port, max_port)
+                self.bind('%s:%s' % (addr, port))
+            except ZMQError as exception:
+                if not exception.errno == zmq.EADDRINUSE:
+                    raise
+            else:
+                return port
+        raise ZMQBindError("Could not bind socket to random port.")
+    
+    def get_hwm(self):
+        """get the High Water Mark
+        
+        On libzmq ≥ 3, this gets SNDHWM if available, otherwise RCVHWM
+        """
+        major = zmq.zmq_version_info()[0]
+        if major >= 3:
+            # return sndhwm, fallback on rcvhwm
+            try:
+                return self.getsockopt(zmq.SNDHWM)
+            except zmq.ZMQError as e:
+                pass
+            
+            return self.getsockopt(zmq.RCVHWM)
+        else:
+            return self.getsockopt(zmq.HWM)
+    
+    def set_hwm(self, value):
+        """set the High Water Mark
+        
+        On libzmq ≥ 3, this sets both SNDHWM and RCVHWM
+        """
+        major = zmq.zmq_version_info()[0]
+        if major >= 3:
+            raised = None
+            try:
+                self.sndhwm = value
+            except Exception as e:
+                raised = e
+            try:
+                self.rcvhwm = value
+            except Exception:
+                raised = e
+            
+            if raised:
+                raise raised
+        else:
+            return self.setsockopt(zmq.HWM, value)
+    
+    hwm = property(get_hwm, set_hwm,
+        """property for High Water Mark
+        
+        Setting hwm sets both SNDHWM and RCVHWM as appropriate.
+        It gets SNDHWM if available, otherwise RCVHWM.
+        """
+    )
+    
+    #-------------------------------------------------------------------------
+    # Sending and receiving messages
+    #-------------------------------------------------------------------------
+
+    def send_multipart(self, msg_parts, flags=0, copy=True, track=False):
+        """send a sequence of buffers as a multipart message
+        
+        The zmq.SNDMORE flag is added to all msg parts before the last.
+
+        Parameters
+        ----------
+        msg_parts : iterable
+            A sequence of objects to send as a multipart message. Each element
+            can be any sendable object (Frame, bytes, buffer-providers)
+        flags : int, optional
+            SNDMORE is handled automatically for frames before the last.
+        copy : bool, optional
+            Should the frame(s) be sent in a copying or non-copying manner.
+        track : bool, optional
+            Should the frame(s) be tracked for notification that ZMQ has
+            finished with it (ignored if copy=True).
+    
+        Returns
+        -------
+        None : if copy or not track
+        MessageTracker : if track and not copy
+            a MessageTracker object, whose `pending` property will
+            be True until the last send is completed.
+        """
+        for msg in msg_parts[:-1]:
+            self.send(msg, SNDMORE|flags, copy=copy, track=track)
+        # Send the last part without the extra SNDMORE flag.
+        return self.send(msg_parts[-1], flags, copy=copy, track=track)
+
+    def recv_multipart(self, flags=0, copy=True, track=False):
+        """receive a multipart message as a list of bytes or Frame objects
+
+        Parameters
+        ----------
+        flags : int, optional
+            Any supported flag: NOBLOCK. If NOBLOCK is set, this method
+            will raise a ZMQError with EAGAIN if a message is not ready.
+            If NOBLOCK is not set, then this method will block until a
+            message arrives.
+        copy : bool, optional
+            Should the message frame(s) be received in a copying or non-copying manner?
+            If False a Frame object is returned for each part, if True a copy of
+            the bytes is made for each frame.
+        track : bool, optional
+            Should the message frame(s) be tracked for notification that ZMQ has
+            finished with it? (ignored if copy=True)
+        
+        Returns
+        -------
+        msg_parts : list
+            A list of frames in the multipart message; either Frames or bytes,
+            depending on `copy`.
+    
+        """
+        parts = [self.recv(flags, copy=copy, track=track)]
+        # have first part already, only loop while more to receive
+        while self.getsockopt(zmq.RCVMORE):
+            part = self.recv(flags, copy=copy, track=track)
+            parts.append(part)
+    
+        return parts
+
+    def send_string(self, u, flags=0, copy=True, encoding='utf-8'):
+        """send a Python unicode string as a message with an encoding
+    
+        0MQ communicates with raw bytes, so you must encode/decode
+        text (unicode on py2, str on py3) around 0MQ.
+        
+        Parameters
+        ----------
+        u : Python unicode string (unicode on py2, str on py3)
+            The unicode string to send.
+        flags : int, optional
+            Any valid send flag.
+        encoding : str [default: 'utf-8']
+            The encoding to be used
+        """
+        if not isinstance(u, basestring):
+            raise TypeError("unicode/str objects only")
+        return self.send(u.encode(encoding), flags=flags, copy=copy)
+    
+    send_unicode = send_string
+    
+    def recv_string(self, flags=0, encoding='utf-8'):
+        """receive a unicode string, as sent by send_string
+    
+        Parameters
+        ----------
+        flags : int
+            Any valid recv flag.
+        encoding : str [default: 'utf-8']
+            The encoding to be used
+
+        Returns
+        -------
+        s : unicode string (unicode on py2, str on py3)
+            The Python unicode string that arrives as encoded bytes.
+        """
+        b = self.recv(flags=flags)
+        return b.decode(encoding)
+    
+    recv_unicode = recv_string
+    
+    def send_pyobj(self, obj, flags=0, protocol=-1):
+        """send a Python object as a message using pickle to serialize
+
+        Parameters
+        ----------
+        obj : Python object
+            The Python object to send.
+        flags : int
+            Any valid send flag.
+        protocol : int
+            The pickle protocol number to use. Default of -1 will select
+            the highest supported number. Use 0 for multiple platform
+            support.
+        """
+        msg = pickle.dumps(obj, protocol)
+        return self.send(msg, flags)
+
+    def recv_pyobj(self, flags=0):
+        """receive a Python object as a message using pickle to serialize
+
+        Parameters
+        ----------
+        flags : int
+            Any valid recv flag.
+
+        Returns
+        -------
+        obj : Python object
+            The Python object that arrives as a message.
+        """
+        s = self.recv(flags)
+        return pickle.loads(s)
+
+    def send_json(self, obj, flags=0, **kwargs):
+        """send a Python object as a message using json to serialize
+        
+        Keyword arguments are passed on to json.dumps
+        
+        Parameters
+        ----------
+        obj : Python object
+            The Python object to send
+        flags : int
+            Any valid send flag
+        """
+        msg = jsonapi.dumps(obj, **kwargs)
+        return self.send(msg, flags)
+
+    def recv_json(self, flags=0, **kwargs):
+        """receive a Python object as a message using json to serialize
+
+        Keyword arguments are passed on to json.loads
+        
+        Parameters
+        ----------
+        flags : int
+            Any valid recv flag.
+
+        Returns
+        -------
+        obj : Python object
+            The Python object that arrives as a message.
+        """
+        msg = self.recv(flags)
+        return jsonapi.loads(msg, **kwargs)
+    
+    _poller_class = Poller
+
+    def poll(self, timeout=None, flags=POLLIN):
+        """poll the socket for events
+        
+        The default is to poll forever for incoming
+        events.  Timeout is in milliseconds, if specified.
+
+        Parameters
+        ----------
+        timeout : int [default: None]
+            The timeout (in milliseconds) to wait for an event. If unspecified
+            (or specified None), will wait forever for an event.
+        flags : bitfield (int) [default: POLLIN]
+            The event flags to poll for (any combination of POLLIN|POLLOUT).
+            The default is to check for incoming events (POLLIN).
+
+        Returns
+        -------
+        events : bitfield (int)
+            The events that are ready and waiting.  Will be 0 if no events were ready
+            by the time timeout was reached.
+        """
+
+        if self.closed:
+            raise ZMQError(ENOTSUP)
+
+        p = self._poller_class()
+        p.register(self, flags)
+        evts = dict(p.poll(timeout))
+        # return 0 if no events, otherwise return event bitfield
+        return evts.get(self, 0)
+
+    def get_monitor_socket(self, events=None, addr=None):
+        """Return a connected PAIR socket ready to receive the event notifications.
+        
+        .. versionadded:: libzmq-4.0
+        .. versionadded:: 14.0
+        
+        Parameters
+        ----------
+        events : bitfield (int) [default: ZMQ_EVENTS_ALL]
+            The bitmask defining which events are wanted.
+        addr :  string [default: None]
+            The optional endpoint for the monitoring sockets.
+
+        Returns
+        -------
+        socket :  (PAIR)
+            The socket is already connected and ready to receive messages.
+        """
+        # safe-guard, method only available on libzmq >= 4
+        if zmq.zmq_version_info() < (4,):
+            raise NotImplementedError("get_monitor_socket requires libzmq >= 4, have %s" % zmq.zmq_version())
+        if addr is None:
+            # create endpoint name from internal fd
+            addr = "inproc://monitor.s-%d" % self.FD
+        if events is None:
+            # use all events
+            events = zmq.EVENT_ALL
+        # attach monitoring socket
+        self.monitor(addr, events)
+        # create new PAIR socket and connect it
+        ret = self.context.socket(zmq.PAIR)
+        ret.connect(addr)
+        return ret
+
+    def disable_monitor(self):
+        """Shutdown the PAIR socket (created using get_monitor_socket)
+        that is serving socket events.
+        
+        .. versionadded:: 14.4
+        """
+        self.monitor(None, 0)
+
+
+__all__ = ['Socket']
diff --git a/zmq/sugar/tracker.py b/zmq/sugar/tracker.py
new file mode 100644
index 0000000..fb8c007
--- /dev/null
+++ b/zmq/sugar/tracker.py
@@ -0,0 +1,120 @@
+"""Tracker for zero-copy messages with 0MQ."""
+
+# Copyright (C) PyZMQ Developers
+# Distributed under the terms of the Modified BSD License.
+
+import time
+
+try:
+    # below 3.3
+    from threading import _Event as Event
+except (ImportError, AttributeError):
+    # python throws ImportError, cython throws AttributeError
+    from threading import Event
+
+from zmq.error import NotDone
+from zmq.backend import Frame
+
+class MessageTracker(object):
+    """MessageTracker(*towatch)
+
+    A class for tracking if 0MQ is done using one or more messages.
+
+    When you send a 0MQ message, it is not sent immediately. The 0MQ IO thread
+    sends the message at some later time. Often you want to know when 0MQ has
+    actually sent the message though. This is complicated by the fact that
+    a single 0MQ message can be sent multiple times using different sockets.
+    This class allows you to track all of the 0MQ usages of a message.
+
+    Parameters
+    ----------
+    *towatch : tuple of Event, MessageTracker, Message instances.
+        This list of objects to track. This class can track the low-level
+        Events used by the Message class, other MessageTrackers or
+        actual Messages.
+    """
+    events = None
+    peers = None
+
+    def __init__(self, *towatch):
+        """MessageTracker(*towatch)
+
+        Create a message tracker to track a set of mesages.
+
+        Parameters
+        ----------
+        *towatch : tuple of Event, MessageTracker, Message instances.
+            This list of objects to track. This class can track the low-level
+            Events used by the Message class, other MessageTrackers or 
+            actual Messages.
+        """
+        self.events = set()
+        self.peers = set()
+        for obj in towatch:
+            if isinstance(obj, Event):
+                self.events.add(obj)
+            elif isinstance(obj, MessageTracker):
+                self.peers.add(obj)
+            elif isinstance(obj, Frame):
+                if not obj.tracker:
+                    raise ValueError("Not a tracked message")
+                self.peers.add(obj.tracker)
+            else:
+                raise TypeError("Require Events or Message Frames, not %s"%type(obj))
+    
+    @property
+    def done(self):
+        """Is 0MQ completely done with the message(s) being tracked?"""
+        for evt in self.events:
+            if not evt.is_set():
+                return False
+        for pm in self.peers:
+            if not pm.done:
+                return False
+        return True
+    
+    def wait(self, timeout=-1):
+        """mt.wait(timeout=-1)
+
+        Wait for 0MQ to be done with the message or until `timeout`.
+
+        Parameters
+        ----------
+        timeout : float [default: -1, wait forever]
+            Maximum time in (s) to wait before raising NotDone.
+
+        Returns
+        -------
+        None
+            if done before `timeout`
+        
+        Raises
+        ------
+        NotDone
+            if `timeout` reached before I am done.
+        """
+        tic = time.time()
+        if timeout is False or timeout < 0:
+            remaining = 3600*24*7 # a week
+        else:
+            remaining = timeout
+        done = False
+        for evt in self.events:
+            if remaining < 0:
+                raise NotDone
+            evt.wait(timeout=remaining)
+            if not evt.is_set():
+                raise NotDone
+            toc = time.time()
+            remaining -= (toc-tic)
+            tic = toc
+        
+        for peer in self.peers:
+            if remaining < 0:
+                raise NotDone
+            peer.wait(timeout=remaining)
+            toc = time.time()
+            remaining -= (toc-tic)
+            tic = toc
+
+__all__ = ['MessageTracker']
\ No newline at end of file
diff --git a/zmq/sugar/version.py b/zmq/sugar/version.py
new file mode 100644
index 0000000..f4c4b57
--- /dev/null
+++ b/zmq/sugar/version.py
@@ -0,0 +1,48 @@
+"""PyZMQ and 0MQ version functions."""
+
+# Copyright (C) PyZMQ Developers
+# Distributed under the terms of the Modified BSD License.
+
+
+from zmq.backend import zmq_version_info
+
+
+VERSION_MAJOR = 14
+VERSION_MINOR = 4
+VERSION_PATCH = 1
+VERSION_EXTRA = ""
+__version__ = '%i.%i.%i' % (VERSION_MAJOR, VERSION_MINOR, VERSION_PATCH)
+
+if VERSION_EXTRA:
+    __version__ = "%s-%s" % (__version__, VERSION_EXTRA)
+    version_info = (VERSION_MAJOR, VERSION_MINOR, VERSION_PATCH, float('inf'))
+else:
+    version_info = (VERSION_MAJOR, VERSION_MINOR, VERSION_PATCH)
+
+__revision__ = ''
+
+def pyzmq_version():
+    """return the version of pyzmq as a string"""
+    if __revision__:
+        return '@'.join([__version__,__revision__[:6]])
+    else:
+        return __version__
+
+def pyzmq_version_info():
+    """return the pyzmq version as a tuple of at least three numbers
+    
+    If pyzmq is a development version, `inf` will be appended after the third integer.
+    """
+    return version_info
+
+
+def zmq_version():
+    """return the version of libzmq as a string"""
+    return "%i.%i.%i" % zmq_version_info()
+
+
+__all__ = ['zmq_version', 'zmq_version_info',
+           'pyzmq_version','pyzmq_version_info',
+           '__version__', '__revision__'
+]
+
diff --git a/zmq/tests/__init__.py b/zmq/tests/__init__.py
new file mode 100644
index 0000000..325a3f1
--- /dev/null
+++ b/zmq/tests/__init__.py
@@ -0,0 +1,211 @@
+# Copyright (c) PyZMQ Developers.
+# Distributed under the terms of the Modified BSD License.
+
+import functools
+import sys
+import time
+from threading import Thread
+
+from unittest import TestCase
+
+import zmq
+from zmq.utils import jsonapi
+
+try:
+    import gevent
+    from zmq import green as gzmq
+    have_gevent = True
+except ImportError:
+    have_gevent = False
+
+try:
+    from unittest import SkipTest
+except ImportError:
+    try:
+        from nose import SkipTest
+    except ImportError:
+        class SkipTest(Exception):
+            pass
+
+PYPY = 'PyPy' in sys.version
+
+#-----------------------------------------------------------------------------
+# skip decorators (directly from unittest)
+#-----------------------------------------------------------------------------
+
+_id = lambda x: x
+
+def skip(reason):
+    """
+    Unconditionally skip a test.
+    """
+    def decorator(test_item):
+        if not (isinstance(test_item, type) and issubclass(test_item, TestCase)):
+            @functools.wraps(test_item)
+            def skip_wrapper(*args, **kwargs):
+                raise SkipTest(reason)
+            test_item = skip_wrapper
+
+        test_item.__unittest_skip__ = True
+        test_item.__unittest_skip_why__ = reason
+        return test_item
+    return decorator
+
+def skip_if(condition, reason="Skipped"):
+    """
+    Skip a test if the condition is true.
+    """
+    if condition:
+        return skip(reason)
+    return _id
+
+skip_pypy = skip_if(PYPY, "Doesn't work on PyPy")
+
+#-----------------------------------------------------------------------------
+# Base test class
+#-----------------------------------------------------------------------------
+
+class BaseZMQTestCase(TestCase):
+    green = False
+    
+    @property
+    def Context(self):
+        if self.green:
+            return gzmq.Context
+        else:
+            return zmq.Context
+    
+    def socket(self, socket_type):
+        s = self.context.socket(socket_type)
+        self.sockets.append(s)
+        return s
+    
+    def setUp(self):
+        if self.green and not have_gevent:
+                raise SkipTest("requires gevent")
+        self.context = self.Context.instance()
+        self.sockets = []
+    
+    def tearDown(self):
+        contexts = set([self.context])
+        while self.sockets:
+            sock = self.sockets.pop()
+            contexts.add(sock.context) # in case additional contexts are created
+            sock.close(0)
+        for ctx in contexts:
+            t = Thread(target=ctx.term)
+            t.daemon = True
+            t.start()
+            t.join(timeout=2)
+            if t.is_alive():
+                # reset Context.instance, so the failure to term doesn't corrupt subsequent tests
+                zmq.sugar.context.Context._instance = None
+                raise RuntimeError("context could not terminate, open sockets likely remain in test")
+
+    def create_bound_pair(self, type1=zmq.PAIR, type2=zmq.PAIR, interface='tcp://127.0.0.1'):
+        """Create a bound socket pair using a random port."""
+        s1 = self.context.socket(type1)
+        s1.setsockopt(zmq.LINGER, 0)
+        port = s1.bind_to_random_port(interface)
+        s2 = self.context.socket(type2)
+        s2.setsockopt(zmq.LINGER, 0)
+        s2.connect('%s:%s' % (interface, port))
+        self.sockets.extend([s1,s2])
+        return s1, s2
+
+    def ping_pong(self, s1, s2, msg):
+        s1.send(msg)
+        msg2 = s2.recv()
+        s2.send(msg2)
+        msg3 = s1.recv()
+        return msg3
+
+    def ping_pong_json(self, s1, s2, o):
+        if jsonapi.jsonmod is None:
+            raise SkipTest("No json library")
+        s1.send_json(o)
+        o2 = s2.recv_json()
+        s2.send_json(o2)
+        o3 = s1.recv_json()
+        return o3
+
+    def ping_pong_pyobj(self, s1, s2, o):
+        s1.send_pyobj(o)
+        o2 = s2.recv_pyobj()
+        s2.send_pyobj(o2)
+        o3 = s1.recv_pyobj()
+        return o3
+
+    def assertRaisesErrno(self, errno, func, *args, **kwargs):
+        try:
+            func(*args, **kwargs)
+        except zmq.ZMQError as e:
+            self.assertEqual(e.errno, errno, "wrong error raised, expected '%s' \
+got '%s'" % (zmq.ZMQError(errno), zmq.ZMQError(e.errno)))
+        else:
+            self.fail("Function did not raise any error")
+    
+    def _select_recv(self, multipart, socket, **kwargs):
+        """call recv[_multipart] in a way that raises if there is nothing to receive"""
+        if zmq.zmq_version_info() >= (3,1,0):
+            # zmq 3.1 has a bug, where poll can return false positives,
+            # so we wait a little bit just in case
+            # See LIBZMQ-280 on JIRA
+            time.sleep(0.1)
+        
+        r,w,x = zmq.select([socket], [], [], timeout=5)
+        assert len(r) > 0, "Should have received a message"
+        kwargs['flags'] = zmq.DONTWAIT | kwargs.get('flags', 0)
+        
+        recv = socket.recv_multipart if multipart else socket.recv
+        return recv(**kwargs)
+        
+    def recv(self, socket, **kwargs):
+        """call recv in a way that raises if there is nothing to receive"""
+        return self._select_recv(False, socket, **kwargs)
+
+    def recv_multipart(self, socket, **kwargs):
+        """call recv_multipart in a way that raises if there is nothing to receive"""
+        return self._select_recv(True, socket, **kwargs)
+    
+
+class PollZMQTestCase(BaseZMQTestCase):
+    pass
+
+class GreenTest:
+    """Mixin for making green versions of test classes"""
+    green = True
+    
+    def assertRaisesErrno(self, errno, func, *args, **kwargs):
+        if errno == zmq.EAGAIN:
+            raise SkipTest("Skipping because we're green.")
+        try:
+            func(*args, **kwargs)
+        except zmq.ZMQError:
+            e = sys.exc_info()[1]
+            self.assertEqual(e.errno, errno, "wrong error raised, expected '%s' \
+got '%s'" % (zmq.ZMQError(errno), zmq.ZMQError(e.errno)))
+        else:
+            self.fail("Function did not raise any error")
+
+    def tearDown(self):
+        contexts = set([self.context])
+        while self.sockets:
+            sock = self.sockets.pop()
+            contexts.add(sock.context) # in case additional contexts are created
+            sock.close()
+        try:
+            gevent.joinall([gevent.spawn(ctx.term) for ctx in contexts], timeout=2, raise_error=True)
+        except gevent.Timeout:
+            raise RuntimeError("context could not terminate, open sockets likely remain in test")
+    
+    def skip_green(self):
+        raise SkipTest("Skipping because we are green")
+
+def skip_green(f):
+    def skipping_test(self, *args, **kwargs):
+        if self.green:
+            raise SkipTest("Skipping because we are green")
+        else:
+            return f(self, *args, **kwargs)
+    return skipping_test
diff --git a/zmq/tests/test_auth.py b/zmq/tests/test_auth.py
new file mode 100644
index 0000000..d350f61
--- /dev/null
+++ b/zmq/tests/test_auth.py
@@ -0,0 +1,431 @@
+# -*- coding: utf8 -*-
+
+# Copyright (C) PyZMQ Developers
+# Distributed under the terms of the Modified BSD License.
+
+import logging
+import os
+import shutil
+import sys
+import tempfile
+
+import zmq.auth
+from zmq.auth.ioloop import IOLoopAuthenticator
+from zmq.auth.thread import ThreadAuthenticator
+
+from zmq.eventloop import ioloop, zmqstream
+from zmq.tests import (BaseZMQTestCase, SkipTest)
+
+class BaseAuthTestCase(BaseZMQTestCase):
+    def setUp(self):
+        if zmq.zmq_version_info() < (4,0):
+            raise SkipTest("security is new in libzmq 4.0")
+        try:
+            zmq.curve_keypair()
+        except zmq.ZMQError:
+            raise SkipTest("security requires libzmq to be linked against libsodium")
+        super(BaseAuthTestCase, self).setUp()
+        # enable debug logging while we run tests
+        logging.getLogger('zmq.auth').setLevel(logging.DEBUG)
+        self.auth = self.make_auth()
+        self.auth.start()
+        self.base_dir, self.public_keys_dir, self.secret_keys_dir = self.create_certs()
+    
+    def make_auth(self):
+        raise NotImplementedError()
+    
+    def tearDown(self):
+        if self.auth:
+            self.auth.stop()
+            self.auth = None
+        self.remove_certs(self.base_dir)
+        super(BaseAuthTestCase, self).tearDown()
+    
+    def create_certs(self):
+        """Create CURVE certificates for a test"""
+
+        # Create temporary CURVE keypairs for this test run. We create all keys in a
+        # temp directory and then move them into the appropriate private or public
+        # directory.
+
+        base_dir = tempfile.mkdtemp()
+        keys_dir = os.path.join(base_dir, 'certificates')
+        public_keys_dir = os.path.join(base_dir, 'public_keys')
+        secret_keys_dir = os.path.join(base_dir, 'private_keys')
+
+        os.mkdir(keys_dir)
+        os.mkdir(public_keys_dir)
+        os.mkdir(secret_keys_dir)
+
+        server_public_file, server_secret_file = zmq.auth.create_certificates(keys_dir, "server")
+        client_public_file, client_secret_file = zmq.auth.create_certificates(keys_dir, "client")
+
+        for key_file in os.listdir(keys_dir):
+            if key_file.endswith(".key"):
+                shutil.move(os.path.join(keys_dir, key_file),
+                            os.path.join(public_keys_dir, '.'))
+
+        for key_file in os.listdir(keys_dir):
+            if key_file.endswith(".key_secret"):
+                shutil.move(os.path.join(keys_dir, key_file),
+                            os.path.join(secret_keys_dir, '.'))
+
+        return (base_dir, public_keys_dir, secret_keys_dir)
+
+    def remove_certs(self, base_dir):
+        """Remove certificates for a test"""
+        shutil.rmtree(base_dir)
+
+    def load_certs(self, secret_keys_dir):
+        """Return server and client certificate keys"""
+        server_secret_file = os.path.join(secret_keys_dir, "server.key_secret")
+        client_secret_file = os.path.join(secret_keys_dir, "client.key_secret")
+
+        server_public, server_secret = zmq.auth.load_certificate(server_secret_file)
+        client_public, client_secret = zmq.auth.load_certificate(client_secret_file)
+
+        return server_public, server_secret, client_public, client_secret
+
+
+class TestThreadAuthentication(BaseAuthTestCase):
+    """Test authentication running in a thread"""
+
+    def make_auth(self):
+        return ThreadAuthenticator(self.context)
+
+    def can_connect(self, server, client):
+        """Check if client can connect to server using tcp transport"""
+        result = False
+        iface = 'tcp://127.0.0.1'
+        port = server.bind_to_random_port(iface)
+        client.connect("%s:%i" % (iface, port))
+        msg = [b"Hello World"]
+        server.send_multipart(msg)
+        if client.poll(1000):
+            rcvd_msg = client.recv_multipart()
+            self.assertEqual(rcvd_msg, msg)
+            result = True
+        return result
+
+    def test_null(self):
+        """threaded auth - NULL"""
+        # A default NULL connection should always succeed, and not
+        # go through our authentication infrastructure at all.
+        self.auth.stop()
+        self.auth = None
+        
+        server = self.socket(zmq.PUSH)
+        client = self.socket(zmq.PULL)
+        self.assertTrue(self.can_connect(server, client))
+
+        # By setting a domain we switch on authentication for NULL sockets,
+        # though no policies are configured yet. The client connection
+        # should still be allowed.
+        server = self.socket(zmq.PUSH)
+        server.zap_domain = b'global'
+        client = self.socket(zmq.PULL)
+        self.assertTrue(self.can_connect(server, client))
+
+    def test_blacklist(self):
+        """threaded auth - Blacklist"""
+        # Blacklist 127.0.0.1, connection should fail
+        self.auth.deny('127.0.0.1')
+        server = self.socket(zmq.PUSH)
+        # By setting a domain we switch on authentication for NULL sockets,
+        # though no policies are configured yet.
+        server.zap_domain = b'global'
+        client = self.socket(zmq.PULL)
+        self.assertFalse(self.can_connect(server, client))
+
+    def test_whitelist(self):
+        """threaded auth - Whitelist"""
+        # Whitelist 127.0.0.1, connection should pass"
+        self.auth.allow('127.0.0.1')
+        server = self.socket(zmq.PUSH)
+        # By setting a domain we switch on authentication for NULL sockets,
+        # though no policies are configured yet.
+        server.zap_domain = b'global'
+        client = self.socket(zmq.PULL)
+        self.assertTrue(self.can_connect(server, client))
+
+    def test_plain(self):
+        """threaded auth - PLAIN"""
+
+        # Try PLAIN authentication - without configuring server, connection should fail
+        server = self.socket(zmq.PUSH)
+        server.plain_server = True
+        client = self.socket(zmq.PULL)
+        client.plain_username = b'admin'
+        client.plain_password = b'Password'
+        self.assertFalse(self.can_connect(server, client))
+
+        # Try PLAIN authentication - with server configured, connection should pass
+        server = self.socket(zmq.PUSH)
+        server.plain_server = True
+        client = self.socket(zmq.PULL)
+        client.plain_username = b'admin'
+        client.plain_password = b'Password'
+        self.auth.configure_plain(domain='*', passwords={'admin': 'Password'})
+        self.assertTrue(self.can_connect(server, client))
+
+        # Try PLAIN authentication - with bogus credentials, connection should fail
+        server = self.socket(zmq.PUSH)
+        server.plain_server = True
+        client = self.socket(zmq.PULL)
+        client.plain_username = b'admin'
+        client.plain_password = b'Bogus'
+        self.assertFalse(self.can_connect(server, client))
+
+        # Remove authenticator and check that a normal connection works
+        self.auth.stop()
+        self.auth = None
+
+        server = self.socket(zmq.PUSH)
+        client = self.socket(zmq.PULL)
+        self.assertTrue(self.can_connect(server, client))
+        client.close()
+        server.close()
+
+    def test_curve(self):
+        """threaded auth - CURVE"""
+        self.auth.allow('127.0.0.1')
+        certs = self.load_certs(self.secret_keys_dir)
+        server_public, server_secret, client_public, client_secret = certs
+
+        #Try CURVE authentication - without configuring server, connection should fail
+        server = self.socket(zmq.PUSH)
+        server.curve_publickey = server_public
+        server.curve_secretkey = server_secret
+        server.curve_server = True
+        client = self.socket(zmq.PULL)
+        client.curve_publickey = client_public
+        client.curve_secretkey = client_secret
+        client.curve_serverkey = server_public
+        self.assertFalse(self.can_connect(server, client))
+
+        #Try CURVE authentication - with server configured to CURVE_ALLOW_ANY, connection should pass
+        self.auth.configure_curve(domain='*', location=zmq.auth.CURVE_ALLOW_ANY)
+        server = self.socket(zmq.PUSH)
+        server.curve_publickey = server_public
+        server.curve_secretkey = server_secret
+        server.curve_server = True
+        client = self.socket(zmq.PULL)
+        client.curve_publickey = client_public
+        client.curve_secretkey = client_secret
+        client.curve_serverkey = server_public
+        self.assertTrue(self.can_connect(server, client))
+
+        # Try CURVE authentication - with server configured, connection should pass
+        self.auth.configure_curve(domain='*', location=self.public_keys_dir)
+        server = self.socket(zmq.PUSH)
+        server.curve_publickey = server_public
+        server.curve_secretkey = server_secret
+        server.curve_server = True
+        client = self.socket(zmq.PULL)
+        client.curve_publickey = client_public
+        client.curve_secretkey = client_secret
+        client.curve_serverkey = server_public
+        self.assertTrue(self.can_connect(server, client))
+
+        # Remove authenticator and check that a normal connection works
+        self.auth.stop()
+        self.auth = None
+
+        # Try connecting using NULL and no authentication enabled, connection should pass
+        server = self.socket(zmq.PUSH)
+        client = self.socket(zmq.PULL)
+        self.assertTrue(self.can_connect(server, client))
+
+
+def with_ioloop(method, expect_success=True):
+    """decorator for running tests with an IOLoop"""
+    def test_method(self):
+        r = method(self)
+        
+        loop = self.io_loop
+        if expect_success:
+            self.pullstream.on_recv(self.on_message_succeed)
+        else:
+            self.pullstream.on_recv(self.on_message_fail)
+        
+        t = loop.time()
+        loop.add_callback(self.attempt_connection)
+        loop.add_callback(self.send_msg)
+        if expect_success:
+            loop.add_timeout(t + 1, self.on_test_timeout_fail)
+        else:
+            loop.add_timeout(t + 1, self.on_test_timeout_succeed)
+        
+        loop.start()
+        if self.fail_msg:
+            self.fail(self.fail_msg)
+        
+        return r
+    return test_method
+
+def should_auth(method):
+    return with_ioloop(method, True)
+
+def should_not_auth(method):
+    return with_ioloop(method, False)
+
+class TestIOLoopAuthentication(BaseAuthTestCase):
+    """Test authentication running in ioloop"""
+
+    def setUp(self):
+        self.fail_msg = None
+        self.io_loop = ioloop.IOLoop()
+        super(TestIOLoopAuthentication, self).setUp()
+        self.server = self.socket(zmq.PUSH)
+        self.client = self.socket(zmq.PULL)
+        self.pushstream = zmqstream.ZMQStream(self.server, self.io_loop)
+        self.pullstream = zmqstream.ZMQStream(self.client, self.io_loop)
+    
+    def make_auth(self):
+        return IOLoopAuthenticator(self.context, io_loop=self.io_loop)
+
+    def tearDown(self):
+        if self.auth:
+            self.auth.stop()
+            self.auth = None
+        self.io_loop.close(all_fds=True)
+        super(TestIOLoopAuthentication, self).tearDown()
+
+    def attempt_connection(self):
+        """Check if client can connect to server using tcp transport"""
+        iface = 'tcp://127.0.0.1'
+        port = self.server.bind_to_random_port(iface)
+        self.client.connect("%s:%i" % (iface, port))
+
+    def send_msg(self):
+        """Send a message from server to a client"""
+        msg = [b"Hello World"]
+        self.pushstream.send_multipart(msg)
+    
+    def on_message_succeed(self, frames):
+        """A message was received, as expected."""
+        if frames != [b"Hello World"]:
+            self.fail_msg = "Unexpected message received"
+        self.io_loop.stop()
+
+    def on_message_fail(self, frames):
+        """A message was received, unexpectedly."""
+        self.fail_msg = 'Received messaged unexpectedly, security failed'
+        self.io_loop.stop()
+
+    def on_test_timeout_succeed(self):
+        """Test timer expired, indicates test success"""
+        self.io_loop.stop()
+
+    def on_test_timeout_fail(self):
+        """Test timer expired, indicates test failure"""
+        self.fail_msg = 'Test timed out'
+        self.io_loop.stop()
+
+    @should_auth
+    def test_none(self):
+        """ioloop auth - NONE"""
+        # A default NULL connection should always succeed, and not
+        # go through our authentication infrastructure at all.
+        # no auth should be running
+        self.auth.stop()
+        self.auth = None
+
+    @should_auth
+    def test_null(self):
+        """ioloop auth - NULL"""
+        # By setting a domain we switch on authentication for NULL sockets,
+        # though no policies are configured yet. The client connection
+        # should still be allowed.
+        self.server.zap_domain = b'global'
+
+    @should_not_auth
+    def test_blacklist(self):
+        """ioloop auth - Blacklist"""
+        # Blacklist 127.0.0.1, connection should fail
+        self.auth.deny('127.0.0.1')
+        self.server.zap_domain = b'global'
+
+    @should_auth
+    def test_whitelist(self):
+        """ioloop auth - Whitelist"""
+        # Whitelist 127.0.0.1, which overrides the blacklist, connection should pass"
+        self.auth.allow('127.0.0.1')
+
+        self.server.setsockopt(zmq.ZAP_DOMAIN, b'global')
+
+    @should_not_auth
+    def test_plain_unconfigured_server(self):
+        """ioloop auth - PLAIN, unconfigured server"""
+        self.client.plain_username = b'admin'
+        self.client.plain_password = b'Password'
+        # Try PLAIN authentication - without configuring server, connection should fail
+        self.server.plain_server = True
+
+    @should_auth
+    def test_plain_configured_server(self):
+        """ioloop auth - PLAIN, configured server"""
+        self.client.plain_username = b'admin'
+        self.client.plain_password = b'Password'
+        # Try PLAIN authentication - with server configured, connection should pass
+        self.server.plain_server = True
+        self.auth.configure_plain(domain='*', passwords={'admin': 'Password'})
+
+    @should_not_auth
+    def test_plain_bogus_credentials(self):
+        """ioloop auth - PLAIN, bogus credentials"""
+        self.client.plain_username = b'admin'
+        self.client.plain_password = b'Bogus'
+        self.server.plain_server = True
+
+        self.auth.configure_plain(domain='*', passwords={'admin': 'Password'})
+
+    @should_not_auth
+    def test_curve_unconfigured_server(self):
+        """ioloop auth - CURVE, unconfigured server"""
+        certs = self.load_certs(self.secret_keys_dir)
+        server_public, server_secret, client_public, client_secret = certs
+
+        self.auth.allow('127.0.0.1')
+
+        self.server.curve_publickey = server_public
+        self.server.curve_secretkey = server_secret
+        self.server.curve_server = True
+
+        self.client.curve_publickey = client_public
+        self.client.curve_secretkey = client_secret
+        self.client.curve_serverkey = server_public
+
+    @should_auth
+    def test_curve_allow_any(self):
+        """ioloop auth - CURVE, CURVE_ALLOW_ANY"""
+        certs = self.load_certs(self.secret_keys_dir)
+        server_public, server_secret, client_public, client_secret = certs
+
+        self.auth.allow('127.0.0.1')
+        self.auth.configure_curve(domain='*', location=zmq.auth.CURVE_ALLOW_ANY)
+
+        self.server.curve_publickey = server_public
+        self.server.curve_secretkey = server_secret
+        self.server.curve_server = True
+
+        self.client.curve_publickey = client_public
+        self.client.curve_secretkey = client_secret
+        self.client.curve_serverkey = server_public
+
+    @should_auth
+    def test_curve_configured_server(self):
+        """ioloop auth - CURVE, configured server"""
+        self.auth.allow('127.0.0.1')
+        certs = self.load_certs(self.secret_keys_dir)
+        server_public, server_secret, client_public, client_secret = certs
+
+        self.auth.configure_curve(domain='*', location=self.public_keys_dir)
+
+        self.server.curve_publickey = server_public
+        self.server.curve_secretkey = server_secret
+        self.server.curve_server = True
+
+        self.client.curve_publickey = client_public
+        self.client.curve_secretkey = client_secret
+        self.client.curve_serverkey = server_public
diff --git a/zmq/tests/test_cffi_backend.py b/zmq/tests/test_cffi_backend.py
new file mode 100644
index 0000000..1f85eeb
--- /dev/null
+++ b/zmq/tests/test_cffi_backend.py
@@ -0,0 +1,310 @@
+# -*- coding: utf8 -*-
+
+import sys
+import time
+
+from unittest import TestCase
+
+from zmq.tests import BaseZMQTestCase, SkipTest
+
+try:
+    from zmq.backend.cffi import (
+        zmq_version_info,
+        PUSH, PULL, IDENTITY,
+        REQ, REP, POLLIN, POLLOUT,
+    )
+    from zmq.backend.cffi._cffi import ffi, C
+    have_ffi_backend = True
+except ImportError:
+    have_ffi_backend = False
+
+
+class TestCFFIBackend(TestCase):
+    
+    def setUp(self):
+        if not have_ffi_backend or not 'PyPy' in sys.version:
+            raise SkipTest('PyPy Tests Only')
+
+    def test_zmq_version_info(self):
+        version = zmq_version_info()
+
+        assert version[0] in range(2,11)
+
+    def test_zmq_ctx_new_destroy(self):
+        ctx = C.zmq_ctx_new()
+
+        assert ctx != ffi.NULL
+        assert 0 == C.zmq_ctx_destroy(ctx)
+
+    def test_zmq_socket_open_close(self):
+        ctx = C.zmq_ctx_new()
+        socket = C.zmq_socket(ctx, PUSH)
+
+        assert ctx != ffi.NULL
+        assert ffi.NULL != socket
+        assert 0 == C.zmq_close(socket)
+        assert 0 == C.zmq_ctx_destroy(ctx)
+
+    def test_zmq_setsockopt(self):
+        ctx = C.zmq_ctx_new()
+        socket = C.zmq_socket(ctx, PUSH)
+
+        identity = ffi.new('char[3]', 'zmq')
+        ret = C.zmq_setsockopt(socket, IDENTITY, ffi.cast('void*', identity), 3)
+
+        assert ret == 0
+        assert ctx != ffi.NULL
+        assert ffi.NULL != socket
+        assert 0 == C.zmq_close(socket)
+        assert 0 == C.zmq_ctx_destroy(ctx)
+
+    def test_zmq_getsockopt(self):
+        ctx = C.zmq_ctx_new()
+        socket = C.zmq_socket(ctx, PUSH)
+
+        identity = ffi.new('char[]', 'zmq')
+        ret = C.zmq_setsockopt(socket, IDENTITY, ffi.cast('void*', identity), 3)
+        assert ret == 0
+
+        option_len = ffi.new('size_t*', 3)
+        option = ffi.new('char*')
+        ret = C.zmq_getsockopt(socket,
+                            IDENTITY,
+                            ffi.cast('void*', option),
+                            option_len)
+
+        assert ret == 0
+        assert ffi.string(ffi.cast('char*', option))[0] == "z"
+        assert ffi.string(ffi.cast('char*', option))[1] == "m"
+        assert ffi.string(ffi.cast('char*', option))[2] == "q"
+        assert ctx != ffi.NULL
+        assert ffi.NULL != socket
+        assert 0 == C.zmq_close(socket)
+        assert 0 == C.zmq_ctx_destroy(ctx)
+
+    def test_zmq_bind(self):
+        ctx = C.zmq_ctx_new()
+        socket = C.zmq_socket(ctx, 8)
+
+        assert 0 == C.zmq_bind(socket, 'tcp://*:4444')
+        assert ctx != ffi.NULL
+        assert ffi.NULL != socket
+        assert 0 == C.zmq_close(socket)
+        assert 0 == C.zmq_ctx_destroy(ctx)
+
+    def test_zmq_bind_connect(self):
+        ctx = C.zmq_ctx_new()
+
+        socket1 = C.zmq_socket(ctx, PUSH)
+        socket2 = C.zmq_socket(ctx, PULL)
+
+        assert 0 == C.zmq_bind(socket1, 'tcp://*:4444')
+        assert 0 == C.zmq_connect(socket2, 'tcp://127.0.0.1:4444')
+        assert ctx != ffi.NULL
+        assert ffi.NULL != socket1
+        assert ffi.NULL != socket2
+        assert 0 == C.zmq_close(socket1)
+        assert 0 == C.zmq_close(socket2)
+        assert 0 == C.zmq_ctx_destroy(ctx)
+
+    def test_zmq_msg_init_close(self):
+        zmq_msg = ffi.new('zmq_msg_t*')
+
+        assert ffi.NULL != zmq_msg
+        assert 0 == C.zmq_msg_init(zmq_msg)
+        assert 0 == C.zmq_msg_close(zmq_msg)
+
+    def test_zmq_msg_init_size(self):
+        zmq_msg = ffi.new('zmq_msg_t*')
+
+        assert ffi.NULL != zmq_msg
+        assert 0 == C.zmq_msg_init_size(zmq_msg, 10)
+        assert 0 == C.zmq_msg_close(zmq_msg)
+
+    def test_zmq_msg_init_data(self):
+        zmq_msg = ffi.new('zmq_msg_t*')
+        message = ffi.new('char[5]', 'Hello')
+
+        assert 0 == C.zmq_msg_init_data(zmq_msg,
+                                        ffi.cast('void*', message),
+                                        5,
+                                        ffi.NULL,
+                                        ffi.NULL)
+
+        assert ffi.NULL != zmq_msg
+        assert 0 == C.zmq_msg_close(zmq_msg)
+
+    def test_zmq_msg_data(self):
+        zmq_msg = ffi.new('zmq_msg_t*')
+        message = ffi.new('char[]', 'Hello')
+        assert 0 == C.zmq_msg_init_data(zmq_msg,
+                                        ffi.cast('void*', message),
+                                        5,
+                                        ffi.NULL,
+                                        ffi.NULL)
+
+        data = C.zmq_msg_data(zmq_msg)
+
+        assert ffi.NULL != zmq_msg
+        assert ffi.string(ffi.cast("char*", data)) == 'Hello'
+        assert 0 == C.zmq_msg_close(zmq_msg)
+
+
+    def test_zmq_send(self):
+        ctx = C.zmq_ctx_new()
+
+        sender = C.zmq_socket(ctx, REQ)
+        receiver = C.zmq_socket(ctx, REP)
+
+        assert 0 == C.zmq_bind(receiver, 'tcp://*:7777')
+        assert 0 == C.zmq_connect(sender, 'tcp://127.0.0.1:7777')
+
+        time.sleep(0.1)
+
+        zmq_msg = ffi.new('zmq_msg_t*')
+        message = ffi.new('char[5]', 'Hello')
+
+        C.zmq_msg_init_data(zmq_msg,
+                            ffi.cast('void*', message),
+                            ffi.cast('size_t', 5),
+                            ffi.NULL,
+                            ffi.NULL)
+
+        assert 5 == C.zmq_msg_send(zmq_msg, sender, 0)
+        assert 0 == C.zmq_msg_close(zmq_msg)
+        assert C.zmq_close(sender) == 0
+        assert C.zmq_close(receiver) == 0
+        assert C.zmq_ctx_destroy(ctx) == 0
+
+    def test_zmq_recv(self):
+        ctx = C.zmq_ctx_new()
+
+        sender = C.zmq_socket(ctx, REQ)
+        receiver = C.zmq_socket(ctx, REP)
+
+        assert 0 == C.zmq_bind(receiver, 'tcp://*:2222')
+        assert 0 == C.zmq_connect(sender, 'tcp://127.0.0.1:2222')
+
+        time.sleep(0.1)
+
+        zmq_msg = ffi.new('zmq_msg_t*')
+        message = ffi.new('char[5]', 'Hello')
+
+        C.zmq_msg_init_data(zmq_msg,
+                            ffi.cast('void*', message),
+                            ffi.cast('size_t', 5),
+                            ffi.NULL,
+                            ffi.NULL)
+
+        zmq_msg2 = ffi.new('zmq_msg_t*')
+        C.zmq_msg_init(zmq_msg2)
+
+        assert 5 == C.zmq_msg_send(zmq_msg, sender, 0)
+        assert 5 == C.zmq_msg_recv(zmq_msg2, receiver, 0)
+        assert 5 == C.zmq_msg_size(zmq_msg2)
+        assert b"Hello" == ffi.buffer(C.zmq_msg_data(zmq_msg2),
+                                      C.zmq_msg_size(zmq_msg2))[:]
+        assert C.zmq_close(sender) == 0
+        assert C.zmq_close(receiver) == 0
+        assert C.zmq_ctx_destroy(ctx) == 0
+
+    def test_zmq_poll(self):
+        ctx = C.zmq_ctx_new()
+
+        sender = C.zmq_socket(ctx, REQ)
+        receiver = C.zmq_socket(ctx, REP)
+
+        r1 = C.zmq_bind(receiver, 'tcp://*:3333')
+        r2 = C.zmq_connect(sender, 'tcp://127.0.0.1:3333')
+
+        zmq_msg = ffi.new('zmq_msg_t*')
+        message = ffi.new('char[5]', 'Hello')
+
+        C.zmq_msg_init_data(zmq_msg,
+                            ffi.cast('void*', message),
+                            ffi.cast('size_t', 5),
+                            ffi.NULL,
+                            ffi.NULL)
+
+        receiver_pollitem = ffi.new('zmq_pollitem_t*')
+        receiver_pollitem.socket = receiver
+        receiver_pollitem.fd = 0
+        receiver_pollitem.events = POLLIN | POLLOUT
+        receiver_pollitem.revents = 0
+
+        ret = C.zmq_poll(ffi.NULL, 0, 0)
+        assert ret == 0
+
+        ret = C.zmq_poll(receiver_pollitem, 1, 0)
+        assert ret == 0
+
+        ret = C.zmq_msg_send(zmq_msg, sender, 0)
+        print(ffi.string(C.zmq_strerror(C.zmq_errno())))
+        assert ret == 5
+
+        time.sleep(0.2)
+
+        ret = C.zmq_poll(receiver_pollitem, 1, 0)
+        assert ret == 1
+
+        assert int(receiver_pollitem.revents) & POLLIN
+        assert not int(receiver_pollitem.revents) & POLLOUT
+
+        zmq_msg2 = ffi.new('zmq_msg_t*')
+        C.zmq_msg_init(zmq_msg2)
+
+        ret_recv = C.zmq_msg_recv(zmq_msg2, receiver, 0)
+        assert ret_recv == 5
+
+        assert 5 == C.zmq_msg_size(zmq_msg2)
+        assert b"Hello" == ffi.buffer(C.zmq_msg_data(zmq_msg2),
+                                    C.zmq_msg_size(zmq_msg2))[:]
+
+        sender_pollitem = ffi.new('zmq_pollitem_t*')
+        sender_pollitem.socket = sender
+        sender_pollitem.fd = 0
+        sender_pollitem.events = POLLIN | POLLOUT
+        sender_pollitem.revents = 0
+
+        ret = C.zmq_poll(sender_pollitem, 1, 0)
+        assert ret == 0
+
+        zmq_msg_again = ffi.new('zmq_msg_t*')
+        message_again = ffi.new('char[11]', 'Hello Again')
+
+        C.zmq_msg_init_data(zmq_msg_again,
+                            ffi.cast('void*', message_again),
+                            ffi.cast('size_t', 11),
+                            ffi.NULL,
+                            ffi.NULL)
+
+        assert 11 == C.zmq_msg_send(zmq_msg_again, receiver, 0)
+
+        time.sleep(0.2)
+
+        assert 0 <= C.zmq_poll(sender_pollitem, 1, 0)
+        assert int(sender_pollitem.revents) & POLLIN
+        assert 11 == C.zmq_msg_recv(zmq_msg2, sender, 0)
+        assert 11 == C.zmq_msg_size(zmq_msg2)
+        assert b"Hello Again" == ffi.buffer(C.zmq_msg_data(zmq_msg2),
+                                            int(C.zmq_msg_size(zmq_msg2)))[:]
+        assert 0 == C.zmq_close(sender)
+        assert 0 == C.zmq_close(receiver)
+        assert 0 == C.zmq_ctx_destroy(ctx)
+        assert 0 == C.zmq_msg_close(zmq_msg)
+        assert 0 == C.zmq_msg_close(zmq_msg2)
+        assert 0 == C.zmq_msg_close(zmq_msg_again)
+
+    def test_zmq_stopwatch_functions(self):
+        stopwatch = C.zmq_stopwatch_start()
+        ret = C.zmq_stopwatch_stop(stopwatch)
+
+        assert ffi.NULL != stopwatch
+        assert 0 < int(ret)
+
+    def test_zmq_sleep(self):
+        try:
+            C.zmq_sleep(1)
+        except Exception as e:
+            raise AssertionError("Error executing zmq_sleep(int)")
+
diff --git a/zmq/tests/test_constants.py b/zmq/tests/test_constants.py
new file mode 100644
index 0000000..d32b2b4
--- /dev/null
+++ b/zmq/tests/test_constants.py
@@ -0,0 +1,104 @@
+# Copyright (C) PyZMQ Developers
+# Distributed under the terms of the Modified BSD License.
+
+import json
+from unittest import TestCase
+
+import zmq
+
+from zmq.utils import constant_names
+from zmq.sugar import constants as sugar_constants
+from zmq.backend import constants as backend_constants
+
+all_set = set(constant_names.all_names)
+
+class TestConstants(TestCase):
+    
+    def _duplicate_test(self, namelist, listname):
+        """test that a given list has no duplicates"""
+        dupes = {}
+        for name in set(namelist):
+            cnt = namelist.count(name)
+            if cnt > 1:
+                dupes[name] = cnt
+        if dupes:
+            self.fail("The following names occur more than once in %s: %s" % (listname, json.dumps(dupes, indent=2)))
+    
+    def test_duplicate_all(self):
+        return self._duplicate_test(constant_names.all_names, "all_names")
+    
+    def _change_key(self, change, version):
+        """return changed-in key"""
+        return "%s-in %d.%d.%d" % tuple([change] + list(version))
+
+    def test_duplicate_changed(self):
+        all_changed = []
+        for change in ("new", "removed"):
+            d = getattr(constant_names, change + "_in")
+            for version, namelist in d.items():
+                all_changed.extend(namelist)
+                self._duplicate_test(namelist, self._change_key(change, version))
+        
+        self._duplicate_test(all_changed, "all-changed")
+    
+    def test_changed_in_all(self):
+        missing = {}
+        for change in ("new", "removed"):
+            d = getattr(constant_names, change + "_in")
+            for version, namelist in d.items():
+                key = self._change_key(change, version)
+                for name in namelist:
+                    if name not in all_set:
+                        if key not in missing:
+                            missing[key] = []
+                        missing[key].append(name)
+        
+        if missing:
+            self.fail(
+                "The following names are missing in `all_names`: %s" % json.dumps(missing, indent=2)
+            )
+    
+    def test_no_negative_constants(self):
+        for name in sugar_constants.__all__:
+            self.assertNotEqual(getattr(zmq, name), sugar_constants._UNDEFINED)
+    
+    def test_undefined_constants(self):
+        all_aliases = []
+        for alias_group in sugar_constants.aliases:
+            all_aliases.extend(alias_group)
+        
+        for name in all_set.difference(all_aliases):
+            raw = getattr(backend_constants, name)
+            if raw == sugar_constants._UNDEFINED:
+                self.assertRaises(AttributeError, getattr, zmq, name)
+            else:
+                self.assertEqual(getattr(zmq, name), raw)
+    
+    def test_new(self):
+        zmq_version = zmq.zmq_version_info()
+        for version, new_names in constant_names.new_in.items():
+            should_have = zmq_version >= version
+            for name in new_names:
+                try:
+                    value = getattr(zmq, name)
+                except AttributeError:
+                    if should_have:
+                        self.fail("AttributeError: zmq.%s" % name)
+                else:
+                    if not should_have:
+                        self.fail("Shouldn't have: zmq.%s=%s" % (name, value))
+
+    def test_removed(self):
+        zmq_version = zmq.zmq_version_info()
+        for version, new_names in constant_names.removed_in.items():
+            should_have = zmq_version < version
+            for name in new_names:
+                try:
+                    value = getattr(zmq, name)
+                except AttributeError:
+                    if should_have:
+                        self.fail("AttributeError: zmq.%s" % name)
+                else:
+                    if not should_have:
+                        self.fail("Shouldn't have: zmq.%s=%s" % (name, value))
+
diff --git a/zmq/tests/test_context.py b/zmq/tests/test_context.py
new file mode 100644
index 0000000..e328077
--- /dev/null
+++ b/zmq/tests/test_context.py
@@ -0,0 +1,257 @@
+# Copyright (C) PyZMQ Developers
+# Distributed under the terms of the Modified BSD License.
+
+import gc
+import sys
+import time
+from threading import Thread, Event
+
+import zmq
+from zmq.tests import (
+    BaseZMQTestCase, have_gevent, GreenTest, skip_green, PYPY, SkipTest,
+)
+
+
+class TestContext(BaseZMQTestCase):
+
+    def test_init(self):
+        c1 = self.Context()
+        self.assert_(isinstance(c1, self.Context))
+        del c1
+        c2 = self.Context()
+        self.assert_(isinstance(c2, self.Context))
+        del c2
+        c3 = self.Context()
+        self.assert_(isinstance(c3, self.Context))
+        del c3
+
+    def test_dir(self):
+        ctx = self.Context()
+        self.assertTrue('socket' in dir(ctx))
+        if zmq.zmq_version_info() > (3,):
+            self.assertTrue('IO_THREADS' in dir(ctx))
+        ctx.term()
+
+    def test_term(self):
+        c = self.Context()
+        c.term()
+        self.assert_(c.closed)
+    
+    def test_context_manager(self):
+        with self.Context() as c:
+            pass
+        self.assert_(c.closed)
+    
+    def test_fail_init(self):
+        self.assertRaisesErrno(zmq.EINVAL, self.Context, -1)
+    
+    def test_term_hang(self):
+        rep,req = self.create_bound_pair(zmq.ROUTER, zmq.DEALER)
+        req.setsockopt(zmq.LINGER, 0)
+        req.send(b'hello', copy=False)
+        req.close()
+        rep.close()
+        self.context.term()
+    
+    def test_instance(self):
+        ctx = self.Context.instance()
+        c2 = self.Context.instance(io_threads=2)
+        self.assertTrue(c2 is ctx)
+        c2.term()
+        c3 = self.Context.instance()
+        c4 = self.Context.instance()
+        self.assertFalse(c3 is c2)
+        self.assertFalse(c3.closed)
+        self.assertTrue(c3 is c4)
+    
+    def test_many_sockets(self):
+        """opening and closing many sockets shouldn't cause problems"""
+        ctx = self.Context()
+        for i in range(16):
+            sockets = [ ctx.socket(zmq.REP) for i in range(65) ]
+            [ s.close() for s in sockets ]
+            # give the reaper a chance
+            time.sleep(1e-2)
+        ctx.term()
+    
+    def test_sockopts(self):
+        """setting socket options with ctx attributes"""
+        ctx = self.Context()
+        ctx.linger = 5
+        self.assertEqual(ctx.linger, 5)
+        s = ctx.socket(zmq.REQ)
+        self.assertEqual(s.linger, 5)
+        self.assertEqual(s.getsockopt(zmq.LINGER), 5)
+        s.close()
+        # check that subscribe doesn't get set on sockets that don't subscribe:
+        ctx.subscribe = b''
+        s = ctx.socket(zmq.REQ)
+        s.close()
+        
+        ctx.term()
+
+    
+    def test_destroy(self):
+        """Context.destroy should close sockets"""
+        ctx = self.Context()
+        sockets = [ ctx.socket(zmq.REP) for i in range(65) ]
+        
+        # close half of the sockets
+        [ s.close() for s in sockets[::2] ]
+        
+        ctx.destroy()
+        # reaper is not instantaneous
+        time.sleep(1e-2)
+        for s in sockets:
+            self.assertTrue(s.closed)
+        
+    def test_destroy_linger(self):
+        """Context.destroy should set linger on closing sockets"""
+        req,rep = self.create_bound_pair(zmq.REQ, zmq.REP)
+        req.send(b'hi')
+        time.sleep(1e-2)
+        self.context.destroy(linger=0)
+        # reaper is not instantaneous
+        time.sleep(1e-2)
+        for s in (req,rep):
+            self.assertTrue(s.closed)
+        
+    def test_term_noclose(self):
+        """Context.term won't close sockets"""
+        ctx = self.Context()
+        s = ctx.socket(zmq.REQ)
+        self.assertFalse(s.closed)
+        t = Thread(target=ctx.term)
+        t.start()
+        t.join(timeout=0.1)
+        self.assertTrue(t.is_alive(), "Context should be waiting")
+        s.close()
+        t.join(timeout=0.1)
+        self.assertFalse(t.is_alive(), "Context should have closed")
+    
+    def test_gc(self):
+        """test close&term by garbage collection alone"""
+        if PYPY:
+            raise SkipTest("GC doesn't work ")
+            
+        # test credit @dln (GH #137):
+        def gcf():
+            def inner():
+                ctx = self.Context()
+                s = ctx.socket(zmq.PUSH)
+            inner()
+            gc.collect()
+        t = Thread(target=gcf)
+        t.start()
+        t.join(timeout=1)
+        self.assertFalse(t.is_alive(), "Garbage collection should have cleaned up context")
+    
+    def test_cyclic_destroy(self):
+        """ctx.destroy should succeed when cyclic ref prevents gc"""
+        # test credit @dln (GH #137):
+        class CyclicReference(object):
+            def __init__(self, parent=None):
+                self.parent = parent
+            
+            def crash(self, sock):
+                self.sock = sock
+                self.child = CyclicReference(self)
+        
+        def crash_zmq():
+            ctx = self.Context()
+            sock = ctx.socket(zmq.PULL)
+            c = CyclicReference()
+            c.crash(sock)
+            ctx.destroy()
+        
+        crash_zmq()
+    
+    def test_term_thread(self):
+        """ctx.term should not crash active threads (#139)"""
+        ctx = self.Context()
+        evt = Event()
+        evt.clear()
+
+        def block():
+            s = ctx.socket(zmq.REP)
+            s.bind_to_random_port('tcp://127.0.0.1')
+            evt.set()
+            try:
+                s.recv()
+            except zmq.ZMQError as e:
+                self.assertEqual(e.errno, zmq.ETERM)
+                return
+            finally:
+                s.close()
+            self.fail("recv should have been interrupted with ETERM")
+        t = Thread(target=block)
+        t.start()
+        
+        evt.wait(1)
+        self.assertTrue(evt.is_set(), "sync event never fired")
+        time.sleep(0.01)
+        ctx.term()
+        t.join(timeout=1)
+        self.assertFalse(t.is_alive(), "term should have interrupted s.recv()")
+    
+    def test_destroy_no_sockets(self):
+        ctx = self.Context()
+        s = ctx.socket(zmq.PUB)
+        s.bind_to_random_port('tcp://127.0.0.1')
+        s.close()
+        ctx.destroy()
+        assert s.closed
+        assert ctx.closed
+    
+    def test_ctx_opts(self):
+        if zmq.zmq_version_info() < (3,):
+            raise SkipTest("context options require libzmq 3")
+        ctx = self.Context()
+        ctx.set(zmq.MAX_SOCKETS, 2)
+        self.assertEqual(ctx.get(zmq.MAX_SOCKETS), 2)
+        ctx.max_sockets = 100
+        self.assertEqual(ctx.max_sockets, 100)
+        self.assertEqual(ctx.get(zmq.MAX_SOCKETS), 100)
+    
+    def test_shadow(self):
+        ctx = self.Context()
+        ctx2 = self.Context.shadow(ctx.underlying)
+        self.assertEqual(ctx.underlying, ctx2.underlying)
+        s = ctx.socket(zmq.PUB)
+        s.close()
+        del ctx2
+        self.assertFalse(ctx.closed)
+        s = ctx.socket(zmq.PUB)
+        ctx2 = self.Context.shadow(ctx.underlying)
+        s2 = ctx2.socket(zmq.PUB)
+        s.close()
+        s2.close()
+        ctx.term()
+        self.assertRaisesErrno(zmq.EFAULT, ctx2.socket, zmq.PUB)
+        del ctx2
+    
+    def test_shadow_pyczmq(self):
+        try:
+            from pyczmq import zctx, zsocket, zstr
+        except Exception:
+            raise SkipTest("Requires pyczmq")
+        
+        ctx = zctx.new()
+        a = zsocket.new(ctx, zmq.PUSH)
+        zsocket.bind(a, "inproc://a")
+        ctx2 = self.Context.shadow_pyczmq(ctx)
+        b = ctx2.socket(zmq.PULL)
+        b.connect("inproc://a")
+        zstr.send(a, b'hi')
+        rcvd = self.recv(b)
+        self.assertEqual(rcvd, b'hi')
+        b.close()
+
+
+if False: # disable green context tests
+    class TestContextGreen(GreenTest, TestContext):
+        """gevent subclass of context tests"""
+        # skip tests that use real threads:
+        test_gc = GreenTest.skip_green
+        test_term_thread = GreenTest.skip_green
+        test_destroy_linger = GreenTest.skip_green
diff --git a/zmq/tests/test_device.py b/zmq/tests/test_device.py
new file mode 100644
index 0000000..f830507
--- /dev/null
+++ b/zmq/tests/test_device.py
@@ -0,0 +1,146 @@
+# Copyright (C) PyZMQ Developers
+# Distributed under the terms of the Modified BSD License.
+
+import time
+
+import zmq
+from zmq import devices
+from zmq.tests import BaseZMQTestCase, SkipTest, have_gevent, GreenTest, PYPY
+from zmq.utils.strtypes import (bytes,unicode,basestring)
+
+if PYPY:
+    # cleanup of shared Context doesn't work on PyPy
+    devices.Device.context_factory = zmq.Context
+
+class TestDevice(BaseZMQTestCase):
+    
+    def test_device_types(self):
+        for devtype in (zmq.STREAMER, zmq.FORWARDER, zmq.QUEUE):
+            dev = devices.Device(devtype, zmq.PAIR, zmq.PAIR)
+            self.assertEqual(dev.device_type, devtype)
+            del dev
+    
+    def test_device_attributes(self):
+        dev = devices.Device(zmq.QUEUE, zmq.SUB, zmq.PUB)
+        self.assertEqual(dev.in_type, zmq.SUB)
+        self.assertEqual(dev.out_type, zmq.PUB)
+        self.assertEqual(dev.device_type, zmq.QUEUE)
+        self.assertEqual(dev.daemon, True)
+        del dev
+    
+    def test_tsdevice_attributes(self):
+        dev = devices.Device(zmq.QUEUE, zmq.SUB, zmq.PUB)
+        self.assertEqual(dev.in_type, zmq.SUB)
+        self.assertEqual(dev.out_type, zmq.PUB)
+        self.assertEqual(dev.device_type, zmq.QUEUE)
+        self.assertEqual(dev.daemon, True)
+        del dev
+        
+    
+    def test_single_socket_forwarder_connect(self):
+        dev = devices.ThreadDevice(zmq.QUEUE, zmq.REP, -1)
+        req = self.context.socket(zmq.REQ)
+        port = req.bind_to_random_port('tcp://127.0.0.1')
+        dev.connect_in('tcp://127.0.0.1:%i'%port)
+        dev.start()
+        time.sleep(.25)
+        msg = b'hello'
+        req.send(msg)
+        self.assertEqual(msg, self.recv(req))
+        del dev
+        req.close()
+        dev = devices.ThreadDevice(zmq.QUEUE, zmq.REP, -1)
+        req = self.context.socket(zmq.REQ)
+        port = req.bind_to_random_port('tcp://127.0.0.1')
+        dev.connect_out('tcp://127.0.0.1:%i'%port)
+        dev.start()
+        time.sleep(.25)
+        msg = b'hello again'
+        req.send(msg)
+        self.assertEqual(msg, self.recv(req))
+        del dev
+        req.close()
+        
+    def test_single_socket_forwarder_bind(self):
+        dev = devices.ThreadDevice(zmq.QUEUE, zmq.REP, -1)
+        # select random port:
+        binder = self.context.socket(zmq.REQ)
+        port = binder.bind_to_random_port('tcp://127.0.0.1')
+        binder.close()
+        time.sleep(0.1)
+        req = self.context.socket(zmq.REQ)
+        req.connect('tcp://127.0.0.1:%i'%port)
+        dev.bind_in('tcp://127.0.0.1:%i'%port)
+        dev.start()
+        time.sleep(.25)
+        msg = b'hello'
+        req.send(msg)
+        self.assertEqual(msg, self.recv(req))
+        del dev
+        req.close()
+        dev = devices.ThreadDevice(zmq.QUEUE, zmq.REP, -1)
+        # select random port:
+        binder = self.context.socket(zmq.REQ)
+        port = binder.bind_to_random_port('tcp://127.0.0.1')
+        binder.close()
+        time.sleep(0.1)
+        req = self.context.socket(zmq.REQ)
+        req.connect('tcp://127.0.0.1:%i'%port)
+        dev.bind_in('tcp://127.0.0.1:%i'%port)
+        dev.start()
+        time.sleep(.25)
+        msg = b'hello again'
+        req.send(msg)
+        self.assertEqual(msg, self.recv(req))
+        del dev
+        req.close()
+    
+    def test_proxy(self):
+        if zmq.zmq_version_info() < (3,2):
+            raise SkipTest("Proxies only in libzmq >= 3")
+        dev = devices.ThreadProxy(zmq.PULL, zmq.PUSH, zmq.PUSH)
+        binder = self.context.socket(zmq.REQ)
+        iface = 'tcp://127.0.0.1'
+        port = binder.bind_to_random_port(iface)
+        port2 = binder.bind_to_random_port(iface)
+        port3 = binder.bind_to_random_port(iface)
+        binder.close()
+        time.sleep(0.1)
+        dev.bind_in("%s:%i" % (iface, port))
+        dev.bind_out("%s:%i" % (iface, port2))
+        dev.bind_mon("%s:%i" % (iface, port3))
+        dev.start()
+        time.sleep(0.25)
+        msg = b'hello'
+        push = self.context.socket(zmq.PUSH)
+        push.connect("%s:%i" % (iface, port))
+        pull = self.context.socket(zmq.PULL)
+        pull.connect("%s:%i" % (iface, port2))
+        mon = self.context.socket(zmq.PULL)
+        mon.connect("%s:%i" % (iface, port3))
+        push.send(msg)
+        self.sockets.extend([push, pull, mon])
+        self.assertEqual(msg, self.recv(pull))
+        self.assertEqual(msg, self.recv(mon))
+
+if have_gevent:
+    import gevent
+    import zmq.green
+    
+    class TestDeviceGreen(GreenTest, BaseZMQTestCase):
+        
+        def test_green_device(self):
+            rep = self.context.socket(zmq.REP)
+            req = self.context.socket(zmq.REQ)
+            self.sockets.extend([req, rep])
+            port = rep.bind_to_random_port('tcp://127.0.0.1')
+            g = gevent.spawn(zmq.green.device, zmq.QUEUE, rep, rep)
+            req.connect('tcp://127.0.0.1:%i' % port)
+            req.send(b'hi')
+            timeout = gevent.Timeout(3)
+            timeout.start()
+            receiver = gevent.spawn(req.recv)
+            self.assertEqual(receiver.get(2), b'hi')
+            timeout.cancel()
+            g.kill(block=True)
+            
diff --git a/zmq/tests/test_error.py b/zmq/tests/test_error.py
new file mode 100644
index 0000000..a2eee14
--- /dev/null
+++ b/zmq/tests/test_error.py
@@ -0,0 +1,43 @@
+# -*- coding: utf8 -*-
+# Copyright (C) PyZMQ Developers
+# Distributed under the terms of the Modified BSD License.
+
+import sys
+import time
+
+import zmq
+from zmq import ZMQError, strerror, Again, ContextTerminated
+from zmq.tests import BaseZMQTestCase
+
+if sys.version_info[0] >= 3:
+    long = int
+
+class TestZMQError(BaseZMQTestCase):
+    
+    def test_strerror(self):
+        """test that strerror gets the right type."""
+        for i in range(10):
+            e = strerror(i)
+            self.assertTrue(isinstance(e, str))
+    
+    def test_zmqerror(self):
+        for errno in range(10):
+            e = ZMQError(errno)
+            self.assertEqual(e.errno, errno)
+            self.assertEqual(str(e), strerror(errno))
+    
+    def test_again(self):
+        s = self.context.socket(zmq.REP)
+        self.assertRaises(Again, s.recv, zmq.NOBLOCK)
+        self.assertRaisesErrno(zmq.EAGAIN, s.recv, zmq.NOBLOCK)
+        s.close()
+    
+    def atest_ctxterm(self):
+        s = self.context.socket(zmq.REP)
+        t = Thread(target=self.context.term)
+        t.start()
+        self.assertRaises(ContextTerminated, s.recv, zmq.NOBLOCK)
+        self.assertRaisesErrno(zmq.TERM, s.recv, zmq.NOBLOCK)
+        s.close()
+        t.join()
+
diff --git a/zmq/tests/test_etc.py b/zmq/tests/test_etc.py
new file mode 100644
index 0000000..ad22406
--- /dev/null
+++ b/zmq/tests/test_etc.py
@@ -0,0 +1,15 @@
+# Copyright (c) PyZMQ Developers.
+# Distributed under the terms of the Modified BSD License.
+
+import sys
+
+import zmq
+
+from . import skip_if
+
+@skip_if(zmq.zmq_version_info() < (4,1), "libzmq < 4.1")
+def test_has():
+    assert not zmq.has('something weird')
+    has_ipc = zmq.has('ipc')
+    not_windows = not sys.platform.startswith('win')
+    assert has_ipc == not_windows
diff --git a/zmq/tests/test_imports.py b/zmq/tests/test_imports.py
new file mode 100644
index 0000000..c0ddfaa
--- /dev/null
+++ b/zmq/tests/test_imports.py
@@ -0,0 +1,62 @@
+# Copyright (C) PyZMQ Developers
+# Distributed under the terms of the Modified BSD License.
+
+import sys
+from unittest import TestCase
+
+class TestImports(TestCase):
+    """Test Imports - the quickest test to ensure that we haven't
+    introduced version-incompatible syntax errors."""
+    
+    def test_toplevel(self):
+        """test toplevel import"""
+        import zmq
+        
+    def test_core(self):
+        """test core imports"""
+        from zmq import Context
+        from zmq import Socket
+        from zmq import Poller
+        from zmq import Frame
+        from zmq import constants
+        from zmq import device, proxy
+        from zmq import Stopwatch
+        from zmq import ( 
+            zmq_version,
+            zmq_version_info,
+            pyzmq_version,
+            pyzmq_version_info,
+        )
+    
+    def test_devices(self):
+        """test device imports"""
+        import zmq.devices
+        from zmq.devices import basedevice
+        from zmq.devices import monitoredqueue
+        from zmq.devices import monitoredqueuedevice
+    
+    def test_log(self):
+        """test log imports"""
+        import zmq.log
+        from zmq.log import handlers
+    
+    def test_eventloop(self):
+        """test eventloop imports"""
+        import zmq.eventloop
+        from zmq.eventloop import ioloop
+        from zmq.eventloop import zmqstream
+        from zmq.eventloop.minitornado.platform import auto
+        from zmq.eventloop.minitornado import ioloop
+    
+    def test_utils(self):
+        """test util imports"""
+        import zmq.utils
+        from zmq.utils import strtypes
+        from zmq.utils import jsonapi
+    
+    def test_ssh(self):
+        """test ssh imports"""
+        from zmq.ssh import tunnel
+    
+
+
diff --git a/zmq/tests/test_ioloop.py b/zmq/tests/test_ioloop.py
new file mode 100644
index 0000000..2a8b115
--- /dev/null
+++ b/zmq/tests/test_ioloop.py
@@ -0,0 +1,113 @@
+# Copyright (C) PyZMQ Developers
+# Distributed under the terms of the Modified BSD License.
+
+import time
+import os
+import threading
+
+import zmq
+from zmq.tests import BaseZMQTestCase
+from zmq.eventloop import ioloop
+from zmq.eventloop.minitornado.ioloop import _Timeout
+try:
+    from tornado.ioloop import PollIOLoop, IOLoop as BaseIOLoop
+except ImportError:
+    from zmq.eventloop.minitornado.ioloop import IOLoop as BaseIOLoop
+
+
+def printer():
+    os.system("say hello")
+    raise Exception
+    print (time.time())
+
+
+class Delay(threading.Thread):
+    def __init__(self, f, delay=1):
+        self.f=f
+        self.delay=delay
+        self.aborted=False
+        self.cond=threading.Condition()
+        super(Delay, self).__init__()
+    
+    def run(self):
+        self.cond.acquire()
+        self.cond.wait(self.delay)
+        self.cond.release()
+        if not self.aborted:
+            self.f()
+    
+    def abort(self):
+        self.aborted=True
+        self.cond.acquire()
+        self.cond.notify()
+        self.cond.release()
+
+
+class TestIOLoop(BaseZMQTestCase):
+
+    def test_simple(self):
+        """simple IOLoop creation test"""
+        loop = ioloop.IOLoop()
+        dc = ioloop.PeriodicCallback(loop.stop, 200, loop)
+        pc = ioloop.PeriodicCallback(lambda : None, 10, loop)
+        pc.start()
+        dc.start()
+        t = Delay(loop.stop,1)
+        t.start()
+        loop.start()
+        if t.isAlive():
+            t.abort()
+        else:
+            self.fail("IOLoop failed to exit")
+    
+    def test_timeout_compare(self):
+        """test timeout comparisons"""
+        loop = ioloop.IOLoop()
+        t = _Timeout(1, 2, loop)
+        t2 = _Timeout(1, 3, loop)
+        self.assertEqual(t < t2, id(t) < id(t2))
+        t2 = _Timeout(2,1, loop)
+        self.assertTrue(t < t2)
+
+    def test_poller_events(self):
+        """Tornado poller implementation maps events correctly"""
+        req,rep = self.create_bound_pair(zmq.REQ, zmq.REP)
+        poller = ioloop.ZMQPoller()
+        poller.register(req, ioloop.IOLoop.READ)
+        poller.register(rep, ioloop.IOLoop.READ)
+        events = dict(poller.poll(0))
+        self.assertEqual(events.get(rep), None)
+        self.assertEqual(events.get(req), None)
+        
+        poller.register(req, ioloop.IOLoop.WRITE)
+        poller.register(rep, ioloop.IOLoop.WRITE)
+        events = dict(poller.poll(1))
+        self.assertEqual(events.get(req), ioloop.IOLoop.WRITE)
+        self.assertEqual(events.get(rep), None)
+        
+        poller.register(rep, ioloop.IOLoop.READ)
+        req.send(b'hi')
+        events = dict(poller.poll(1))
+        self.assertEqual(events.get(rep), ioloop.IOLoop.READ)
+        self.assertEqual(events.get(req), None)
+    
+    def test_instance(self):
+        """Test IOLoop.instance returns the right object"""
+        loop = ioloop.IOLoop.instance()
+        self.assertEqual(loop.__class__, ioloop.IOLoop)
+        loop = BaseIOLoop.instance()
+        self.assertEqual(loop.__class__, ioloop.IOLoop)
+    
+    def test_close_all(self):
+        """Test close(all_fds=True)"""
+        loop = ioloop.IOLoop.instance()
+        req,rep = self.create_bound_pair(zmq.REQ, zmq.REP)
+        loop.add_handler(req, lambda msg: msg, ioloop.IOLoop.READ)
+        loop.add_handler(rep, lambda msg: msg, ioloop.IOLoop.READ)
+        self.assertEqual(req.closed, False)
+        self.assertEqual(rep.closed, False)
+        loop.close(all_fds=True)
+        self.assertEqual(req.closed, True)
+        self.assertEqual(rep.closed, True)
+        
+
diff --git a/zmq/tests/test_log.py b/zmq/tests/test_log.py
new file mode 100644
index 0000000..9206f09
--- /dev/null
+++ b/zmq/tests/test_log.py
@@ -0,0 +1,116 @@
+# encoding: utf-8
+
+# Copyright (C) PyZMQ Developers
+# Distributed under the terms of the Modified BSD License.
+
+
+import logging
+import time
+from unittest import TestCase
+
+import zmq
+from zmq.log import handlers
+from zmq.utils.strtypes import b, u
+from zmq.tests import BaseZMQTestCase
+
+
+class TestPubLog(BaseZMQTestCase):
+    
+    iface = 'inproc://zmqlog'
+    topic= 'zmq'
+    
+    @property
+    def logger(self):
+        # print dir(self)
+        logger = logging.getLogger('zmqtest')
+        logger.setLevel(logging.DEBUG)
+        return logger
+    
+    def connect_handler(self, topic=None):
+        topic = self.topic if topic is None else topic
+        logger = self.logger
+        pub,sub = self.create_bound_pair(zmq.PUB, zmq.SUB)
+        handler = handlers.PUBHandler(pub)
+        handler.setLevel(logging.DEBUG)
+        handler.root_topic = topic
+        logger.addHandler(handler)
+        sub.setsockopt(zmq.SUBSCRIBE, b(topic))
+        time.sleep(0.1)
+        return logger, handler, sub
+    
+    def test_init_iface(self):
+        logger = self.logger
+        ctx = self.context
+        handler = handlers.PUBHandler(self.iface)
+        self.assertFalse(handler.ctx is ctx)
+        self.sockets.append(handler.socket)
+        # handler.ctx.term()
+        handler = handlers.PUBHandler(self.iface, self.context)
+        self.sockets.append(handler.socket)
+        self.assertTrue(handler.ctx is ctx)
+        handler.setLevel(logging.DEBUG)
+        handler.root_topic = self.topic
+        logger.addHandler(handler)
+        sub = ctx.socket(zmq.SUB)
+        self.sockets.append(sub)
+        sub.setsockopt(zmq.SUBSCRIBE, b(self.topic))
+        sub.connect(self.iface)
+        import time; time.sleep(0.25)
+        msg1 = 'message'
+        logger.info(msg1)
+        
+        (topic, msg2) = sub.recv_multipart()
+        self.assertEqual(topic, b'zmq.INFO')
+        self.assertEqual(msg2, b(msg1)+b'\n')
+        logger.removeHandler(handler)
+    
+    def test_init_socket(self):
+        pub,sub = self.create_bound_pair(zmq.PUB, zmq.SUB)
+        logger = self.logger
+        handler = handlers.PUBHandler(pub)
+        handler.setLevel(logging.DEBUG)
+        handler.root_topic = self.topic
+        logger.addHandler(handler)
+        
+        self.assertTrue(handler.socket is pub)
+        self.assertTrue(handler.ctx is pub.context)
+        self.assertTrue(handler.ctx is self.context)
+        sub.setsockopt(zmq.SUBSCRIBE, b(self.topic))
+        import time; time.sleep(0.1)
+        msg1 = 'message'
+        logger.info(msg1)
+        
+        (topic, msg2) = sub.recv_multipart()
+        self.assertEqual(topic, b'zmq.INFO')
+        self.assertEqual(msg2, b(msg1)+b'\n')
+        logger.removeHandler(handler)
+    
+    def test_root_topic(self):
+        logger, handler, sub = self.connect_handler()
+        handler.socket.bind(self.iface)
+        sub2 = sub.context.socket(zmq.SUB)
+        self.sockets.append(sub2)
+        sub2.connect(self.iface)
+        sub2.setsockopt(zmq.SUBSCRIBE, b'')
+        handler.root_topic = b'twoonly'
+        msg1 = 'ignored'
+        logger.info(msg1)
+        self.assertRaisesErrno(zmq.EAGAIN, sub.recv, zmq.NOBLOCK)
+        topic,msg2 = sub2.recv_multipart()
+        self.assertEqual(topic, b'twoonly.INFO')
+        self.assertEqual(msg2, b(msg1)+b'\n')
+        
+        logger.removeHandler(handler)
+    
+    def test_unicode_message(self):
+        logger, handler, sub = self.connect_handler()
+        base_topic = b(self.topic + '.INFO')
+        for msg, expected in [
+            (u('hello'), [base_topic, b('hello\n')]),
+            (u('héllo'), [base_topic, b('héllo\n')]),
+            (u('tøpic::héllo'), [base_topic + b('.tøpic'), b('héllo\n')]),
+        ]:
+            logger.info(msg)
+            received = sub.recv_multipart()
+            self.assertEqual(received, expected)
+
diff --git a/zmq/tests/test_message.py b/zmq/tests/test_message.py
new file mode 100644
index 0000000..d8770bd
--- /dev/null
+++ b/zmq/tests/test_message.py
@@ -0,0 +1,362 @@
+# -*- coding: utf8 -*-
+# Copyright (C) PyZMQ Developers
+# Distributed under the terms of the Modified BSD License.
+
+
+import copy
+import sys
+try:
+    from sys import getrefcount as grc
+except ImportError:
+    grc = None
+
+import time
+from pprint import pprint
+from unittest import TestCase
+
+import zmq
+from zmq.tests import BaseZMQTestCase, SkipTest, skip_pypy, PYPY
+from zmq.utils.strtypes import unicode, bytes, b, u
+
+
+# some useful constants:
+
+x = b'x'
+
+try:
+    view = memoryview
+except NameError:
+    view = buffer
+
+if grc:
+    rc0 = grc(x)
+    v = view(x)
+    view_rc = grc(x) - rc0
+
+def await_gc(obj, rc):
+    """wait for refcount on an object to drop to an expected value
+    
+    Necessary because of the zero-copy gc thread,
+    which can take some time to receive its DECREF message.
+    """
+    for i in range(50):
+        # rc + 2 because of the refs in this function
+        if grc(obj) <= rc + 2:
+            return
+        time.sleep(0.05)
+    
+class TestFrame(BaseZMQTestCase):
+
+    @skip_pypy
+    def test_above_30(self):
+        """Message above 30 bytes are never copied by 0MQ."""
+        for i in range(5, 16):  # 32, 64,..., 65536
+            s = (2**i)*x
+            self.assertEqual(grc(s), 2)
+            m = zmq.Frame(s)
+            self.assertEqual(grc(s), 4)
+            del m
+            await_gc(s, 2)
+            self.assertEqual(grc(s), 2)
+            del s
+
+    def test_str(self):
+        """Test the str representations of the Frames."""
+        for i in range(16):
+            s = (2**i)*x
+            m = zmq.Frame(s)
+            m_str = str(m)
+            m_str_b = b(m_str) # py3compat
+            self.assertEqual(s, m_str_b)
+
+    def test_bytes(self):
+        """Test the Frame.bytes property."""
+        for i in range(1,16):
+            s = (2**i)*x
+            m = zmq.Frame(s)
+            b = m.bytes
+            self.assertEqual(s, m.bytes)
+            if not PYPY:
+                # check that it copies
+                self.assert_(b is not s)
+            # check that it copies only once
+            self.assert_(b is m.bytes)
+
+    def test_unicode(self):
+        """Test the unicode representations of the Frames."""
+        s = u('asdf')
+        self.assertRaises(TypeError, zmq.Frame, s)
+        for i in range(16):
+            s = (2**i)*u('§')
+            m = zmq.Frame(s.encode('utf8'))
+            self.assertEqual(s, unicode(m.bytes,'utf8'))
+
+    def test_len(self):
+        """Test the len of the Frames."""
+        for i in range(16):
+            s = (2**i)*x
+            m = zmq.Frame(s)
+            self.assertEqual(len(s), len(m))
+
+    @skip_pypy
+    def test_lifecycle1(self):
+        """Run through a ref counting cycle with a copy."""
+        for i in range(5, 16):  # 32, 64,..., 65536
+            s = (2**i)*x
+            rc = 2
+            self.assertEqual(grc(s), rc)
+            m = zmq.Frame(s)
+            rc += 2
+            self.assertEqual(grc(s), rc)
+            m2 = copy.copy(m)
+            rc += 1
+            self.assertEqual(grc(s), rc)
+            buf = m2.buffer
+
+            rc += view_rc
+            self.assertEqual(grc(s), rc)
+
+            self.assertEqual(s, b(str(m)))
+            self.assertEqual(s, bytes(m2))
+            self.assertEqual(s, m.bytes)
+            # self.assert_(s is str(m))
+            # self.assert_(s is str(m2))
+            del m2
+            rc -= 1
+            self.assertEqual(grc(s), rc)
+            rc -= view_rc
+            del buf
+            self.assertEqual(grc(s), rc)
+            del m
+            rc -= 2
+            await_gc(s, rc)
+            self.assertEqual(grc(s), rc)
+            self.assertEqual(rc, 2)
+            del s
+
+    @skip_pypy
+    def test_lifecycle2(self):
+        """Run through a different ref counting cycle with a copy."""
+        for i in range(5, 16):  # 32, 64,..., 65536
+            s = (2**i)*x
+            rc = 2
+            self.assertEqual(grc(s), rc)
+            m = zmq.Frame(s)
+            rc += 2
+            self.assertEqual(grc(s), rc)
+            m2 = copy.copy(m)
+            rc += 1
+            self.assertEqual(grc(s), rc)
+            buf = m.buffer
+            rc += view_rc
+            self.assertEqual(grc(s), rc)
+            self.assertEqual(s, b(str(m)))
+            self.assertEqual(s, bytes(m2))
+            self.assertEqual(s, m2.bytes)
+            self.assertEqual(s, m.bytes)
+            # self.assert_(s is str(m))
+            # self.assert_(s is str(m2))
+            del buf
+            self.assertEqual(grc(s), rc)
+            del m
+            # m.buffer is kept until m is del'd
+            rc -= view_rc
+            rc -= 1
+            self.assertEqual(grc(s), rc)
+            del m2
+            rc -= 2
+            await_gc(s, rc)
+            self.assertEqual(grc(s), rc)
+            self.assertEqual(rc, 2)
+            del s
+    
+    @skip_pypy
+    def test_tracker(self):
+        m = zmq.Frame(b'asdf', track=True)
+        self.assertFalse(m.tracker.done)
+        pm = zmq.MessageTracker(m)
+        self.assertFalse(pm.done)
+        del m
+        for i in range(10):
+            if pm.done:
+                break
+            time.sleep(0.1)
+        self.assertTrue(pm.done)
+    
+    def test_no_tracker(self):
+        m = zmq.Frame(b'asdf', track=False)
+        self.assertEqual(m.tracker, None)
+        m2 = copy.copy(m)
+        self.assertEqual(m2.tracker, None)
+        self.assertRaises(ValueError, zmq.MessageTracker, m)
+    
+    @skip_pypy
+    def test_multi_tracker(self):
+        m = zmq.Frame(b'asdf', track=True)
+        m2 = zmq.Frame(b'whoda', track=True)
+        mt = zmq.MessageTracker(m,m2)
+        self.assertFalse(m.tracker.done)
+        self.assertFalse(mt.done)
+        self.assertRaises(zmq.NotDone, mt.wait, 0.1)
+        del m
+        time.sleep(0.1)
+        self.assertRaises(zmq.NotDone, mt.wait, 0.1)
+        self.assertFalse(mt.done)
+        del m2
+        self.assertTrue(mt.wait() is None)
+        self.assertTrue(mt.done)
+        
+    
+    def test_buffer_in(self):
+        """test using a buffer as input"""
+        ins = b("§§¶•ªº˜µ¬˚…∆˙åß∂©œ∑´†≈ç√")
+        m = zmq.Frame(view(ins))
+    
+    def test_bad_buffer_in(self):
+        """test using a bad object"""
+        self.assertRaises(TypeError, zmq.Frame, 5)
+        self.assertRaises(TypeError, zmq.Frame, object())
+        
+    def test_buffer_out(self):
+        """receiving buffered output"""
+        ins = b("§§¶•ªº˜µ¬˚…∆˙åß∂©œ∑´†≈ç√")
+        m = zmq.Frame(ins)
+        outb = m.buffer
+        self.assertTrue(isinstance(outb, view))
+        self.assert_(outb is m.buffer)
+        self.assert_(m.buffer is m.buffer)
+    
+    def test_multisend(self):
+        """ensure that a message remains intact after multiple sends"""
+        a,b = self.create_bound_pair(zmq.PAIR, zmq.PAIR)
+        s = b"message"
+        m = zmq.Frame(s)
+        self.assertEqual(s, m.bytes)
+        
+        a.send(m, copy=False)
+        time.sleep(0.1)
+        self.assertEqual(s, m.bytes)
+        a.send(m, copy=False)
+        time.sleep(0.1)
+        self.assertEqual(s, m.bytes)
+        a.send(m, copy=True)
+        time.sleep(0.1)
+        self.assertEqual(s, m.bytes)
+        a.send(m, copy=True)
+        time.sleep(0.1)
+        self.assertEqual(s, m.bytes)
+        for i in range(4):
+            r = b.recv()
+            self.assertEqual(s,r)
+        self.assertEqual(s, m.bytes)
+    
+    def test_buffer_numpy(self):
+        """test non-copying numpy array messages"""
+        try:
+            import numpy
+        except ImportError:
+            raise SkipTest("numpy required")
+        rand = numpy.random.randint
+        shapes = [ rand(2,16) for i in range(5) ]
+        for i in range(1,len(shapes)+1):
+            shape = shapes[:i]
+            A = numpy.random.random(shape)
+            m = zmq.Frame(A)
+            if view.__name__ == 'buffer':
+                self.assertEqual(A.data, m.buffer)
+                B = numpy.frombuffer(m.buffer,dtype=A.dtype).reshape(A.shape)
+            else:
+                self.assertEqual(memoryview(A), m.buffer)
+                B = numpy.array(m.buffer,dtype=A.dtype).reshape(A.shape)
+            self.assertEqual((A==B).all(), True)
+    
+    def test_memoryview(self):
+        """test messages from memoryview"""
+        major,minor = sys.version_info[:2]
+        if not (major >= 3 or (major == 2 and minor >= 7)):
+            raise SkipTest("memoryviews only in python >= 2.7")
+
+        s = b'carrotjuice'
+        v = memoryview(s)
+        m = zmq.Frame(s)
+        buf = m.buffer
+        s2 = buf.tobytes()
+        self.assertEqual(s2,s)
+        self.assertEqual(m.bytes,s)
+    
+    def test_noncopying_recv(self):
+        """check for clobbering message buffers"""
+        null = b'\0'*64
+        sa,sb = self.create_bound_pair(zmq.PAIR, zmq.PAIR)
+        for i in range(32):
+            # try a few times
+            sb.send(null, copy=False)
+            m = sa.recv(copy=False)
+            mb = m.bytes
+            # buf = view(m)
+            buf = m.buffer
+            del m
+            for i in range(5):
+                ff=b'\xff'*(40 + i*10)
+                sb.send(ff, copy=False)
+                m2 = sa.recv(copy=False)
+                if view.__name__ == 'buffer':
+                    b = bytes(buf)
+                else:
+                    b = buf.tobytes()
+                self.assertEqual(b, null)
+                self.assertEqual(mb, null)
+                self.assertEqual(m2.bytes, ff)
+
+    @skip_pypy
+    def test_buffer_numpy(self):
+        """test non-copying numpy array messages"""
+        try:
+            import numpy
+        except ImportError:
+            raise SkipTest("requires numpy")
+        if sys.version_info < (2,7):
+            raise SkipTest("requires new-style buffer interface (py >= 2.7)")
+        rand = numpy.random.randint
+        shapes = [ rand(2,5) for i in range(5) ]
+        a,b = self.create_bound_pair(zmq.PAIR, zmq.PAIR)
+        dtypes = [int, float, '>i4', 'B']
+        for i in range(1,len(shapes)+1):
+            shape = shapes[:i]
+            for dt in dtypes:
+                A = numpy.empty(shape, dtype=dt)
+                while numpy.isnan(A).any():
+                    # don't let nan sneak in
+                    A = numpy.ndarray(shape, dtype=dt)
+                a.send(A, copy=False)
+                msg = b.recv(copy=False)
+                
+                B = numpy.frombuffer(msg, A.dtype).reshape(A.shape)
+                self.assertEqual(A.shape, B.shape)
+                self.assertTrue((A==B).all())
+            A = numpy.empty(shape, dtype=[('a', int), ('b', float), ('c', 'a32')])
+            A['a'] = 1024
+            A['b'] = 1e9
+            A['c'] = 'hello there'
+            a.send(A, copy=False)
+            msg = b.recv(copy=False)
+            
+            B = numpy.frombuffer(msg, A.dtype).reshape(A.shape)
+            self.assertEqual(A.shape, B.shape)
+            self.assertTrue((A==B).all())
+    
+    def test_frame_more(self):
+        """test Frame.more attribute"""
+        frame = zmq.Frame(b"hello")
+        self.assertFalse(frame.more)
+        sa,sb = self.create_bound_pair(zmq.PAIR, zmq.PAIR)
+        sa.send_multipart([b'hi', b'there'])
+        frame = self.recv(sb, copy=False)
+        self.assertTrue(frame.more)
+        if zmq.zmq_version_info()[0] >= 3 and not PYPY:
+            self.assertTrue(frame.get(zmq.MORE))
+        frame = self.recv(sb, copy=False)
+        self.assertFalse(frame.more)
+        if zmq.zmq_version_info()[0] >= 3 and not PYPY:
+            self.assertFalse(frame.get(zmq.MORE))
+
diff --git a/zmq/tests/test_monitor.py b/zmq/tests/test_monitor.py
new file mode 100644
index 0000000..4f03538
--- /dev/null
+++ b/zmq/tests/test_monitor.py
@@ -0,0 +1,71 @@
+# -*- coding: utf-8 -*-
+# Copyright (C) PyZMQ Developers
+# Distributed under the terms of the Modified BSD License.
+
+
+import sys
+import time
+import struct
+
+from unittest import TestCase
+
+import zmq
+from zmq.tests import BaseZMQTestCase, skip_if, skip_pypy
+from zmq.utils.monitor import recv_monitor_message
+
+skip_lt_4 = skip_if(zmq.zmq_version_info() < (4,), "requires zmq >= 4")
+
+class TestSocketMonitor(BaseZMQTestCase):
+
+    @skip_lt_4
+    def test_monitor(self):
+        """Test monitoring interface for sockets."""
+        s_rep = self.context.socket(zmq.REP)
+        s_req = self.context.socket(zmq.REQ)
+        self.sockets.extend([s_rep, s_req])
+        s_req.bind("tcp://127.0.0.1:6666")
+        # try monitoring the REP socket
+        
+        s_rep.monitor("inproc://monitor.rep", zmq.EVENT_ALL)
+        # create listening socket for monitor
+        s_event = self.context.socket(zmq.PAIR)
+        self.sockets.append(s_event)
+        s_event.connect("inproc://monitor.rep")
+        s_event.linger = 0
+        # test receive event for connect event
+        s_rep.connect("tcp://127.0.0.1:6666")
+        m = recv_monitor_message(s_event)
+        if m['event'] == zmq.EVENT_CONNECT_DELAYED:
+            self.assertEqual(m['endpoint'], b"tcp://127.0.0.1:6666")
+            # test receive event for connected event
+            m = recv_monitor_message(s_event)
+        self.assertEqual(m['event'], zmq.EVENT_CONNECTED)
+        self.assertEqual(m['endpoint'], b"tcp://127.0.0.1:6666")
+
+        # test monitor can be disabled.
+        s_rep.disable_monitor()
+        m = recv_monitor_message(s_event)
+        self.assertEqual(m['event'], zmq.EVENT_MONITOR_STOPPED)
+
+
+    @skip_lt_4
+    def test_monitor_connected(self):
+        """Test connected monitoring socket."""
+        s_rep = self.context.socket(zmq.REP)
+        s_req = self.context.socket(zmq.REQ)
+        self.sockets.extend([s_rep, s_req])
+        s_req.bind("tcp://127.0.0.1:6667")
+        # try monitoring the REP socket
+        # create listening socket for monitor
+        s_event = s_rep.get_monitor_socket()
+        s_event.linger = 0
+        self.sockets.append(s_event)
+        # test receive event for connect event
+        s_rep.connect("tcp://127.0.0.1:6667")
+        m = recv_monitor_message(s_event)
+        if m['event'] == zmq.EVENT_CONNECT_DELAYED:
+            self.assertEqual(m['endpoint'], b"tcp://127.0.0.1:6667")
+            # test receive event for connected event
+            m = recv_monitor_message(s_event)
+        self.assertEqual(m['event'], zmq.EVENT_CONNECTED)
+        self.assertEqual(m['endpoint'], b"tcp://127.0.0.1:6667")
diff --git a/zmq/tests/test_monqueue.py b/zmq/tests/test_monqueue.py
new file mode 100644
index 0000000..e855602
--- /dev/null
+++ b/zmq/tests/test_monqueue.py
@@ -0,0 +1,227 @@
+# Copyright (C) PyZMQ Developers
+# Distributed under the terms of the Modified BSD License.
+
+import time
+from unittest import TestCase
+
+import zmq
+from zmq import devices
+
+from zmq.tests import BaseZMQTestCase, SkipTest, PYPY
+from zmq.utils.strtypes import unicode
+
+
+if PYPY or zmq.zmq_version_info() >= (4,1):
+    # cleanup of shared Context doesn't work on PyPy
+    # there also seems to be a bug in cleanup in libzmq-4.1 (zeromq/libzmq#1052)
+    devices.Device.context_factory = zmq.Context
+
+
+class TestMonitoredQueue(BaseZMQTestCase):
+    
+    sockets = []
+    
+    def build_device(self, mon_sub=b"", in_prefix=b'in', out_prefix=b'out'):
+        self.device = devices.ThreadMonitoredQueue(zmq.PAIR, zmq.PAIR, zmq.PUB,
+                                            in_prefix, out_prefix)
+        alice = self.context.socket(zmq.PAIR)
+        bob = self.context.socket(zmq.PAIR)
+        mon = self.context.socket(zmq.SUB)
+        
+        aport = alice.bind_to_random_port('tcp://127.0.0.1')
+        bport = bob.bind_to_random_port('tcp://127.0.0.1')
+        mport = mon.bind_to_random_port('tcp://127.0.0.1')
+        mon.setsockopt(zmq.SUBSCRIBE, mon_sub)
+        
+        self.device.connect_in("tcp://127.0.0.1:%i"%aport)
+        self.device.connect_out("tcp://127.0.0.1:%i"%bport)
+        self.device.connect_mon("tcp://127.0.0.1:%i"%mport)
+        self.device.start()
+        time.sleep(.2)
+        try:
+            # this is currenlty necessary to ensure no dropped monitor messages
+            # see LIBZMQ-248 for more info
+            mon.recv_multipart(zmq.NOBLOCK)
+        except zmq.ZMQError:
+            pass
+        self.sockets.extend([alice, bob, mon])
+        return alice, bob, mon
+        
+    
+    def teardown_device(self):
+        for socket in self.sockets:
+            socket.close()
+            del socket
+        del self.device
+        
+    def test_reply(self):
+        alice, bob, mon = self.build_device()
+        alices = b"hello bob".split()
+        alice.send_multipart(alices)
+        bobs = self.recv_multipart(bob)
+        self.assertEqual(alices, bobs)
+        bobs = b"hello alice".split()
+        bob.send_multipart(bobs)
+        alices = self.recv_multipart(alice)
+        self.assertEqual(alices, bobs)
+        self.teardown_device()
+    
+    def test_queue(self):
+        alice, bob, mon = self.build_device()
+        alices = b"hello bob".split()
+        alice.send_multipart(alices)
+        alices2 = b"hello again".split()
+        alice.send_multipart(alices2)
+        alices3 = b"hello again and again".split()
+        alice.send_multipart(alices3)
+        bobs = self.recv_multipart(bob)
+        self.assertEqual(alices, bobs)
+        bobs = self.recv_multipart(bob)
+        self.assertEqual(alices2, bobs)
+        bobs = self.recv_multipart(bob)
+        self.assertEqual(alices3, bobs)
+        bobs = b"hello alice".split()
+        bob.send_multipart(bobs)
+        alices = self.recv_multipart(alice)
+        self.assertEqual(alices, bobs)
+        self.teardown_device()
+    
+    def test_monitor(self):
+        alice, bob, mon = self.build_device()
+        alices = b"hello bob".split()
+        alice.send_multipart(alices)
+        alices2 = b"hello again".split()
+        alice.send_multipart(alices2)
+        alices3 = b"hello again and again".split()
+        alice.send_multipart(alices3)
+        bobs = self.recv_multipart(bob)
+        self.assertEqual(alices, bobs)
+        mons = self.recv_multipart(mon)
+        self.assertEqual([b'in']+bobs, mons)
+        bobs = self.recv_multipart(bob)
+        self.assertEqual(alices2, bobs)
+        bobs = self.recv_multipart(bob)
+        self.assertEqual(alices3, bobs)
+        mons = self.recv_multipart(mon)
+        self.assertEqual([b'in']+alices2, mons)
+        bobs = b"hello alice".split()
+        bob.send_multipart(bobs)
+        alices = self.recv_multipart(alice)
+        self.assertEqual(alices, bobs)
+        mons = self.recv_multipart(mon)
+        self.assertEqual([b'in']+alices3, mons)
+        mons = self.recv_multipart(mon)
+        self.assertEqual([b'out']+bobs, mons)
+        self.teardown_device()
+    
+    def test_prefix(self):
+        alice, bob, mon = self.build_device(b"", b'foo', b'bar')
+        alices = b"hello bob".split()
+        alice.send_multipart(alices)
+        alices2 = b"hello again".split()
+        alice.send_multipart(alices2)
+        alices3 = b"hello again and again".split()
+        alice.send_multipart(alices3)
+        bobs = self.recv_multipart(bob)
+        self.assertEqual(alices, bobs)
+        mons = self.recv_multipart(mon)
+        self.assertEqual([b'foo']+bobs, mons)
+        bobs = self.recv_multipart(bob)
+        self.assertEqual(alices2, bobs)
+        bobs = self.recv_multipart(bob)
+        self.assertEqual(alices3, bobs)
+        mons = self.recv_multipart(mon)
+        self.assertEqual([b'foo']+alices2, mons)
+        bobs = b"hello alice".split()
+        bob.send_multipart(bobs)
+        alices = self.recv_multipart(alice)
+        self.assertEqual(alices, bobs)
+        mons = self.recv_multipart(mon)
+        self.assertEqual([b'foo']+alices3, mons)
+        mons = self.recv_multipart(mon)
+        self.assertEqual([b'bar']+bobs, mons)
+        self.teardown_device()
+    
+    def test_monitor_subscribe(self):
+        alice, bob, mon = self.build_device(b"out")
+        alices = b"hello bob".split()
+        alice.send_multipart(alices)
+        alices2 = b"hello again".split()
+        alice.send_multipart(alices2)
+        alices3 = b"hello again and again".split()
+        alice.send_multipart(alices3)
+        bobs = self.recv_multipart(bob)
+        self.assertEqual(alices, bobs)
+        bobs = self.recv_multipart(bob)
+        self.assertEqual(alices2, bobs)
+        bobs = self.recv_multipart(bob)
+        self.assertEqual(alices3, bobs)
+        bobs = b"hello alice".split()
+        bob.send_multipart(bobs)
+        alices = self.recv_multipart(alice)
+        self.assertEqual(alices, bobs)
+        mons = self.recv_multipart(mon)
+        self.assertEqual([b'out']+bobs, mons)
+        self.teardown_device()
+    
+    def test_router_router(self):
+        """test router-router MQ devices"""
+        dev = devices.ThreadMonitoredQueue(zmq.ROUTER, zmq.ROUTER, zmq.PUB, b'in', b'out')
+        self.device = dev
+        dev.setsockopt_in(zmq.LINGER, 0)
+        dev.setsockopt_out(zmq.LINGER, 0)
+        dev.setsockopt_mon(zmq.LINGER, 0)
+        
+        binder = self.context.socket(zmq.DEALER)
+        porta = binder.bind_to_random_port('tcp://127.0.0.1')
+        portb = binder.bind_to_random_port('tcp://127.0.0.1')
+        binder.close()
+        time.sleep(0.1)
+        a = self.context.socket(zmq.DEALER)
+        a.identity = b'a'
+        b = self.context.socket(zmq.DEALER)
+        b.identity = b'b'
+        self.sockets.extend([a, b])
+        
+        a.connect('tcp://127.0.0.1:%i'%porta)
+        dev.bind_in('tcp://127.0.0.1:%i'%porta)
+        b.connect('tcp://127.0.0.1:%i'%portb)
+        dev.bind_out('tcp://127.0.0.1:%i'%portb)
+        dev.start()
+        time.sleep(0.2)
+        if zmq.zmq_version_info() >= (3,1,0):
+            # flush erroneous poll state, due to LIBZMQ-280
+            ping_msg = [ b'ping', b'pong' ]
+            for s in (a,b):
+                s.send_multipart(ping_msg)
+                try:
+                    s.recv(zmq.NOBLOCK)
+                except zmq.ZMQError:
+                    pass
+        msg = [ b'hello', b'there' ]
+        a.send_multipart([b'b']+msg)
+        bmsg = self.recv_multipart(b)
+        self.assertEqual(bmsg, [b'a']+msg)
+        b.send_multipart(bmsg)
+        amsg = self.recv_multipart(a)
+        self.assertEqual(amsg, [b'b']+msg)
+        self.teardown_device()
+    
+    def test_default_mq_args(self):
+        self.device = dev = devices.ThreadMonitoredQueue(zmq.ROUTER, zmq.DEALER, zmq.PUB)
+        dev.setsockopt_in(zmq.LINGER, 0)
+        dev.setsockopt_out(zmq.LINGER, 0)
+        dev.setsockopt_mon(zmq.LINGER, 0)
+        # this will raise if default args are wrong
+        dev.start()
+        self.teardown_device()
+    
+    def test_mq_check_prefix(self):
+        ins = self.context.socket(zmq.ROUTER)
+        outs = self.context.socket(zmq.DEALER)
+        mons = self.context.socket(zmq.PUB)
+        self.sockets.extend([ins, outs, mons])
+        
+        ins = unicode('in')
+        outs = unicode('out')
+        self.assertRaises(TypeError, devices.monitoredqueue, ins, outs, mons)
diff --git a/zmq/tests/test_multipart.py b/zmq/tests/test_multipart.py
new file mode 100644
index 0000000..24d41be
--- /dev/null
+++ b/zmq/tests/test_multipart.py
@@ -0,0 +1,35 @@
+# Copyright (C) PyZMQ Developers
+# Distributed under the terms of the Modified BSD License.
+
+
+import zmq
+
+
+from zmq.tests import BaseZMQTestCase, SkipTest, have_gevent, GreenTest
+
+
+class TestMultipart(BaseZMQTestCase):
+
+    def test_router_dealer(self):
+        router, dealer = self.create_bound_pair(zmq.ROUTER, zmq.DEALER)
+
+        msg1 = b'message1'
+        dealer.send(msg1)
+        ident = self.recv(router)
+        more = router.rcvmore
+        self.assertEqual(more, True)
+        msg2 = self.recv(router)
+        self.assertEqual(msg1, msg2)
+        more = router.rcvmore
+        self.assertEqual(more, False)
+    
+    def test_basic_multipart(self):
+        a,b = self.create_bound_pair(zmq.PAIR, zmq.PAIR)
+        msg = [ b'hi', b'there', b'b']
+        a.send_multipart(msg)
+        recvd = b.recv_multipart()
+        self.assertEqual(msg, recvd)
+
+if have_gevent:
+    class TestMultipartGreen(GreenTest, TestMultipart):
+        pass
diff --git a/zmq/tests/test_pair.py b/zmq/tests/test_pair.py
new file mode 100644
index 0000000..e88c1e8
--- /dev/null
+++ b/zmq/tests/test_pair.py
@@ -0,0 +1,53 @@
+# Copyright (C) PyZMQ Developers
+# Distributed under the terms of the Modified BSD License.
+
+
+import zmq
+
+
+from zmq.tests import BaseZMQTestCase, have_gevent, GreenTest
+
+
+x = b' '
+class TestPair(BaseZMQTestCase):
+
+    def test_basic(self):
+        s1, s2 = self.create_bound_pair(zmq.PAIR, zmq.PAIR)
+
+        msg1 = b'message1'
+        msg2 = self.ping_pong(s1, s2, msg1)
+        self.assertEqual(msg1, msg2)
+
+    def test_multiple(self):
+        s1, s2 = self.create_bound_pair(zmq.PAIR, zmq.PAIR)
+
+        for i in range(10):
+            msg = i*x
+            s1.send(msg)
+
+        for i in range(10):
+            msg = i*x
+            s2.send(msg)
+
+        for i in range(10):
+            msg = s1.recv()
+            self.assertEqual(msg, i*x)
+
+        for i in range(10):
+            msg = s2.recv()
+            self.assertEqual(msg, i*x)
+
+    def test_json(self):
+        s1, s2 = self.create_bound_pair(zmq.PAIR, zmq.PAIR)
+        o = dict(a=10,b=list(range(10)))
+        o2 = self.ping_pong_json(s1, s2, o)
+
+    def test_pyobj(self):
+        s1, s2 = self.create_bound_pair(zmq.PAIR, zmq.PAIR)
+        o = dict(a=10,b=range(10))
+        o2 = self.ping_pong_pyobj(s1, s2, o)
+
+if have_gevent:
+    class TestReqRepGreen(GreenTest, TestPair):
+        pass
+
diff --git a/zmq/tests/test_poll.py b/zmq/tests/test_poll.py
new file mode 100644
index 0000000..57346c8
--- /dev/null
+++ b/zmq/tests/test_poll.py
@@ -0,0 +1,229 @@
+# Copyright (C) PyZMQ Developers
+# Distributed under the terms of the Modified BSD License.
+
+
+import time
+from unittest import TestCase
+
+import zmq
+
+from zmq.tests import PollZMQTestCase, have_gevent, GreenTest
+
+def wait():
+    time.sleep(.25)
+
+
+class TestPoll(PollZMQTestCase):
+
+    Poller = zmq.Poller
+
+    # This test is failing due to this issue:
+    # http://github.com/sustrik/zeromq2/issues#issue/26
+    def test_pair(self):
+        s1, s2 = self.create_bound_pair(zmq.PAIR, zmq.PAIR)
+
+        # Sleep to allow sockets to connect.
+        wait()
+
+        poller = self.Poller()
+        poller.register(s1, zmq.POLLIN|zmq.POLLOUT)
+        poller.register(s2, zmq.POLLIN|zmq.POLLOUT)
+        # Poll result should contain both sockets
+        socks = dict(poller.poll())
+        # Now make sure that both are send ready.
+        self.assertEqual(socks[s1], zmq.POLLOUT)
+        self.assertEqual(socks[s2], zmq.POLLOUT)
+        # Now do a send on both, wait and test for zmq.POLLOUT|zmq.POLLIN
+        s1.send(b'msg1')
+        s2.send(b'msg2')
+        wait()
+        socks = dict(poller.poll())
+        self.assertEqual(socks[s1], zmq.POLLOUT|zmq.POLLIN)
+        self.assertEqual(socks[s2], zmq.POLLOUT|zmq.POLLIN)
+        # Make sure that both are in POLLOUT after recv.
+        s1.recv()
+        s2.recv()
+        socks = dict(poller.poll())
+        self.assertEqual(socks[s1], zmq.POLLOUT)
+        self.assertEqual(socks[s2], zmq.POLLOUT)
+
+        poller.unregister(s1)
+        poller.unregister(s2)
+
+        # Wait for everything to finish.
+        wait()
+
+    def test_reqrep(self):
+        s1, s2 = self.create_bound_pair(zmq.REP, zmq.REQ)
+
+        # Sleep to allow sockets to connect.
+        wait()
+
+        poller = self.Poller()
+        poller.register(s1, zmq.POLLIN|zmq.POLLOUT)
+        poller.register(s2, zmq.POLLIN|zmq.POLLOUT)
+
+        # Make sure that s1 is in state 0 and s2 is in POLLOUT
+        socks = dict(poller.poll())
+        self.assertEqual(s1 in socks, 0)
+        self.assertEqual(socks[s2], zmq.POLLOUT)
+
+        # Make sure that s2 goes immediately into state 0 after send.
+        s2.send(b'msg1')
+        socks = dict(poller.poll())
+        self.assertEqual(s2 in socks, 0)
+
+        # Make sure that s1 goes into POLLIN state after a time.sleep().
+        time.sleep(0.5)
+        socks = dict(poller.poll())
+        self.assertEqual(socks[s1], zmq.POLLIN)
+
+        # Make sure that s1 goes into POLLOUT after recv.
+        s1.recv()
+        socks = dict(poller.poll())
+        self.assertEqual(socks[s1], zmq.POLLOUT)
+
+        # Make sure s1 goes into state 0 after send.
+        s1.send(b'msg2')
+        socks = dict(poller.poll())
+        self.assertEqual(s1 in socks, 0)
+
+        # Wait and then see that s2 is in POLLIN.
+        time.sleep(0.5)
+        socks = dict(poller.poll())
+        self.assertEqual(socks[s2], zmq.POLLIN)
+
+        # Make sure that s2 is in POLLOUT after recv.
+        s2.recv()
+        socks = dict(poller.poll())
+        self.assertEqual(socks[s2], zmq.POLLOUT)
+
+        poller.unregister(s1)
+        poller.unregister(s2)
+
+        # Wait for everything to finish.
+        wait()
+    
+    def test_no_events(self):
+        s1, s2 = self.create_bound_pair(zmq.PAIR, zmq.PAIR)
+        poller = self.Poller()
+        poller.register(s1, zmq.POLLIN|zmq.POLLOUT)
+        poller.register(s2, 0)
+        self.assertTrue(s1 in poller)
+        self.assertFalse(s2 in poller)
+        poller.register(s1, 0)
+        self.assertFalse(s1 in poller)
+
+    def test_pubsub(self):
+        s1, s2 = self.create_bound_pair(zmq.PUB, zmq.SUB)
+        s2.setsockopt(zmq.SUBSCRIBE, b'')
+
+        # Sleep to allow sockets to connect.
+        wait()
+
+        poller = self.Poller()
+        poller.register(s1, zmq.POLLIN|zmq.POLLOUT)
+        poller.register(s2, zmq.POLLIN)
+
+        # Now make sure that both are send ready.
+        socks = dict(poller.poll())
+        self.assertEqual(socks[s1], zmq.POLLOUT)
+        self.assertEqual(s2 in socks, 0)
+        # Make sure that s1 stays in POLLOUT after a send.
+        s1.send(b'msg1')
+        socks = dict(poller.poll())
+        self.assertEqual(socks[s1], zmq.POLLOUT)
+
+        # Make sure that s2 is POLLIN after waiting.
+        wait()
+        socks = dict(poller.poll())
+        self.assertEqual(socks[s2], zmq.POLLIN)
+
+        # Make sure that s2 goes into 0 after recv.
+        s2.recv()
+        socks = dict(poller.poll())
+        self.assertEqual(s2 in socks, 0)
+
+        poller.unregister(s1)
+        poller.unregister(s2)
+
+        # Wait for everything to finish.
+        wait()
+    def test_timeout(self):
+        """make sure Poller.poll timeout has the right units (milliseconds)."""
+        s1, s2 = self.create_bound_pair(zmq.PAIR, zmq.PAIR)
+        poller = self.Poller()
+        poller.register(s1, zmq.POLLIN)
+        tic = time.time()
+        evt = poller.poll(.005)
+        toc = time.time()
+        self.assertTrue(toc-tic < 0.1)
+        tic = time.time()
+        evt = poller.poll(5)
+        toc = time.time()
+        self.assertTrue(toc-tic < 0.1)
+        self.assertTrue(toc-tic > .001)
+        tic = time.time()
+        evt = poller.poll(500)
+        toc = time.time()
+        self.assertTrue(toc-tic < 1)
+        self.assertTrue(toc-tic > 0.1)
+
+class TestSelect(PollZMQTestCase):
+
+    def test_pair(self):
+        s1, s2 = self.create_bound_pair(zmq.PAIR, zmq.PAIR)
+
+        # Sleep to allow sockets to connect.
+        wait()
+
+        rlist, wlist, xlist = zmq.select([s1, s2], [s1, s2], [s1, s2])
+        self.assert_(s1 in wlist)
+        self.assert_(s2 in wlist)
+        self.assert_(s1 not in rlist)
+        self.assert_(s2 not in rlist)
+
+    def test_timeout(self):
+        """make sure select timeout has the right units (seconds)."""
+        s1, s2 = self.create_bound_pair(zmq.PAIR, zmq.PAIR)
+        tic = time.time()
+        r,w,x = zmq.select([s1,s2],[],[],.005)
+        toc = time.time()
+        self.assertTrue(toc-tic < 1)
+        self.assertTrue(toc-tic > 0.001)
+        tic = time.time()
+        r,w,x = zmq.select([s1,s2],[],[],.25)
+        toc = time.time()
+        self.assertTrue(toc-tic < 1)
+        self.assertTrue(toc-tic > 0.1)
+
+
+if have_gevent:
+    import gevent
+    from zmq import green as gzmq
+
+    class TestPollGreen(GreenTest, TestPoll):
+        Poller = gzmq.Poller
+
+        def test_wakeup(self):
+            s1, s2 = self.create_bound_pair(zmq.PAIR, zmq.PAIR)
+            poller = self.Poller()
+            poller.register(s2, zmq.POLLIN)
+
+            tic = time.time()
+            r = gevent.spawn(lambda: poller.poll(10000))
+            s = gevent.spawn(lambda: s1.send(b'msg1'))
+            r.join()
+            toc = time.time()
+            self.assertTrue(toc-tic < 1)
+        
+        def test_socket_poll(self):
+            s1, s2 = self.create_bound_pair(zmq.PAIR, zmq.PAIR)
+
+            tic = time.time()
+            r = gevent.spawn(lambda: s2.poll(10000))
+            s = gevent.spawn(lambda: s1.send(b'msg1'))
+            r.join()
+            toc = time.time()
+            self.assertTrue(toc-tic < 1)
+
diff --git a/zmq/tests/test_pubsub.py b/zmq/tests/test_pubsub.py
new file mode 100644
index 0000000..a3ee22a
--- /dev/null
+++ b/zmq/tests/test_pubsub.py
@@ -0,0 +1,41 @@
+# Copyright (C) PyZMQ Developers
+# Distributed under the terms of the Modified BSD License.
+
+
+import time
+from unittest import TestCase
+
+import zmq
+
+from zmq.tests import BaseZMQTestCase, have_gevent, GreenTest
+
+
+class TestPubSub(BaseZMQTestCase):
+
+    pass
+
+    # We are disabling this test while an issue is being resolved.
+    def test_basic(self):
+        s1, s2 = self.create_bound_pair(zmq.PUB, zmq.SUB)
+        s2.setsockopt(zmq.SUBSCRIBE,b'')
+        time.sleep(0.1)
+        msg1 = b'message'
+        s1.send(msg1)
+        msg2 = s2.recv()  # This is blocking!
+        self.assertEqual(msg1, msg2)
+
+    def test_topic(self):
+        s1, s2 = self.create_bound_pair(zmq.PUB, zmq.SUB)
+        s2.setsockopt(zmq.SUBSCRIBE, b'x')
+        time.sleep(0.1)
+        msg1 = b'message'
+        s1.send(msg1)
+        self.assertRaisesErrno(zmq.EAGAIN, s2.recv, zmq.NOBLOCK)
+        msg1 = b'xmessage'
+        s1.send(msg1)
+        msg2 = s2.recv()
+        self.assertEqual(msg1, msg2)
+
+if have_gevent:
+    class TestPubSubGreen(GreenTest, TestPubSub):
+        pass
diff --git a/zmq/tests/test_reqrep.py b/zmq/tests/test_reqrep.py
new file mode 100644
index 0000000..de17f2b
--- /dev/null
+++ b/zmq/tests/test_reqrep.py
@@ -0,0 +1,62 @@
+# Copyright (C) PyZMQ Developers
+# Distributed under the terms of the Modified BSD License.
+
+
+from unittest import TestCase
+
+import zmq
+from zmq.tests import BaseZMQTestCase, have_gevent, GreenTest
+
+
+class TestReqRep(BaseZMQTestCase):
+
+    def test_basic(self):
+        s1, s2 = self.create_bound_pair(zmq.REQ, zmq.REP)
+
+        msg1 = b'message 1'
+        msg2 = self.ping_pong(s1, s2, msg1)
+        self.assertEqual(msg1, msg2)
+
+    def test_multiple(self):
+        s1, s2 = self.create_bound_pair(zmq.REQ, zmq.REP)
+
+        for i in range(10):
+            msg1 = i*b' '
+            msg2 = self.ping_pong(s1, s2, msg1)
+            self.assertEqual(msg1, msg2)
+
+    def test_bad_send_recv(self):
+        s1, s2 = self.create_bound_pair(zmq.REQ, zmq.REP)
+        
+        if zmq.zmq_version() != '2.1.8':
+            # this doesn't work on 2.1.8
+            for copy in (True,False):
+                self.assertRaisesErrno(zmq.EFSM, s1.recv, copy=copy)
+                self.assertRaisesErrno(zmq.EFSM, s2.send, b'asdf', copy=copy)
+
+        # I have to have this or we die on an Abort trap.
+        msg1 = b'asdf'
+        msg2 = self.ping_pong(s1, s2, msg1)
+        self.assertEqual(msg1, msg2)
+
+    def test_json(self):
+        s1, s2 = self.create_bound_pair(zmq.REQ, zmq.REP)
+        o = dict(a=10,b=list(range(10)))
+        o2 = self.ping_pong_json(s1, s2, o)
+
+    def test_pyobj(self):
+        s1, s2 = self.create_bound_pair(zmq.REQ, zmq.REP)
+        o = dict(a=10,b=range(10))
+        o2 = self.ping_pong_pyobj(s1, s2, o)
+
+    def test_large_msg(self):
+        s1, s2 = self.create_bound_pair(zmq.REQ, zmq.REP)
+        msg1 = 10000*b'X'
+
+        for i in range(10):
+            msg2 = self.ping_pong(s1, s2, msg1)
+            self.assertEqual(msg1, msg2)
+
+if have_gevent:
+    class TestReqRepGreen(GreenTest, TestReqRep):
+        pass
diff --git a/zmq/tests/test_security.py b/zmq/tests/test_security.py
new file mode 100644
index 0000000..687b7e0
--- /dev/null
+++ b/zmq/tests/test_security.py
@@ -0,0 +1,212 @@
+"""Test libzmq security (libzmq >= 3.3.0)"""
+# -*- coding: utf8 -*-
+
+# Copyright (C) PyZMQ Developers
+# Distributed under the terms of the Modified BSD License.
+
+import os
+from threading import Thread
+
+import zmq
+from zmq.tests import (
+    BaseZMQTestCase, SkipTest, PYPY
+)
+from zmq.utils import z85
+
+
+USER = b"admin"
+PASS = b"password"
+
+class TestSecurity(BaseZMQTestCase):
+    
+    def setUp(self):
+        if zmq.zmq_version_info() < (4,0):
+            raise SkipTest("security is new in libzmq 4.0")
+        try:
+            zmq.curve_keypair()
+        except zmq.ZMQError:
+            raise SkipTest("security requires libzmq to be linked against libsodium")
+        super(TestSecurity, self).setUp()
+    
+    
+    def zap_handler(self):
+        socket = self.context.socket(zmq.REP)
+        socket.bind("inproc://zeromq.zap.01")
+        try:
+            msg = self.recv_multipart(socket)
+
+            version, sequence, domain, address, identity, mechanism = msg[:6]
+            if mechanism == b'PLAIN':
+                username, password = msg[6:]
+            elif mechanism == b'CURVE':
+                key = msg[6]
+
+            self.assertEqual(version, b"1.0")
+            self.assertEqual(identity, b"IDENT")
+            reply = [version, sequence]
+            if mechanism == b'CURVE' or \
+                (mechanism == b'PLAIN' and username == USER and password == PASS) or \
+                (mechanism == b'NULL'):
+                reply.extend([
+                    b"200",
+                    b"OK",
+                    b"anonymous",
+                    b"\5Hello\0\0\0\5World",
+                ])
+            else:
+                reply.extend([
+                    b"400",
+                    b"Invalid username or password",
+                    b"",
+                    b"",
+                ])
+            socket.send_multipart(reply)
+        finally:
+            socket.close()
+    
+    def start_zap(self):
+        self.zap_thread = Thread(target=self.zap_handler)
+        self.zap_thread.start()
+    
+    def stop_zap(self):
+        self.zap_thread.join()
+
+    def bounce(self, server, client, test_metadata=True):
+        msg = [os.urandom(64), os.urandom(64)]
+        client.send_multipart(msg)
+        frames = self.recv_multipart(server, copy=False)
+        recvd = list(map(lambda x: x.bytes, frames))
+
+        try:
+            if test_metadata and not PYPY:
+                for frame in frames:
+                    self.assertEqual(frame.get('User-Id'), 'anonymous')
+                    self.assertEqual(frame.get('Hello'), 'World')
+                    self.assertEqual(frame['Socket-Type'], 'DEALER')
+        except zmq.ZMQVersionError:
+            pass
+
+        self.assertEqual(recvd, msg)
+        server.send_multipart(recvd)
+        msg2 = self.recv_multipart(client)
+        self.assertEqual(msg2, msg)
+    
+    def test_null(self):
+        """test NULL (default) security"""
+        server = self.socket(zmq.DEALER)
+        client = self.socket(zmq.DEALER)
+        self.assertEqual(client.MECHANISM, zmq.NULL)
+        self.assertEqual(server.mechanism, zmq.NULL)
+        self.assertEqual(client.plain_server, 0)
+        self.assertEqual(server.plain_server, 0)
+        iface = 'tcp://127.0.0.1'
+        port = server.bind_to_random_port(iface)
+        client.connect("%s:%i" % (iface, port))
+        self.bounce(server, client, False)
+
+    def test_plain(self):
+        """test PLAIN authentication"""
+        server = self.socket(zmq.DEALER)
+        server.identity = b'IDENT'
+        client = self.socket(zmq.DEALER)
+        self.assertEqual(client.plain_username, b'')
+        self.assertEqual(client.plain_password, b'')
+        client.plain_username = USER
+        client.plain_password = PASS
+        self.assertEqual(client.getsockopt(zmq.PLAIN_USERNAME), USER)
+        self.assertEqual(client.getsockopt(zmq.PLAIN_PASSWORD), PASS)
+        self.assertEqual(client.plain_server, 0)
+        self.assertEqual(server.plain_server, 0)
+        server.plain_server = True
+        self.assertEqual(server.mechanism, zmq.PLAIN)
+        self.assertEqual(client.mechanism, zmq.PLAIN)
+        
+        assert not client.plain_server
+        assert server.plain_server
+        
+        self.start_zap()
+        
+        iface = 'tcp://127.0.0.1'
+        port = server.bind_to_random_port(iface)
+        client.connect("%s:%i" % (iface, port))
+        self.bounce(server, client)
+        self.stop_zap()
+
+    def skip_plain_inauth(self):
+        """test PLAIN failed authentication"""
+        server = self.socket(zmq.DEALER)
+        server.identity = b'IDENT'
+        client = self.socket(zmq.DEALER)
+        self.sockets.extend([server, client])
+        client.plain_username = USER
+        client.plain_password = b'incorrect'
+        server.plain_server = True
+        self.assertEqual(server.mechanism, zmq.PLAIN)
+        self.assertEqual(client.mechanism, zmq.PLAIN)
+        
+        self.start_zap()
+        
+        iface = 'tcp://127.0.0.1'
+        port = server.bind_to_random_port(iface)
+        client.connect("%s:%i" % (iface, port))
+        client.send(b'ping')
+        server.rcvtimeo = 250
+        self.assertRaisesErrno(zmq.EAGAIN, server.recv)
+        self.stop_zap()
+    
+    def test_keypair(self):
+        """test curve_keypair"""
+        try:
+            public, secret = zmq.curve_keypair()
+        except zmq.ZMQError:
+            raise SkipTest("CURVE unsupported")
+        
+        self.assertEqual(type(secret), bytes)
+        self.assertEqual(type(public), bytes)
+        self.assertEqual(len(secret), 40)
+        self.assertEqual(len(public), 40)
+        
+        # verify that it is indeed Z85
+        bsecret, bpublic = [ z85.decode(key) for key in (public, secret) ]
+        self.assertEqual(type(bsecret), bytes)
+        self.assertEqual(type(bpublic), bytes)
+        self.assertEqual(len(bsecret), 32)
+        self.assertEqual(len(bpublic), 32)
+        
+    
+    def test_curve(self):
+        """test CURVE encryption"""
+        server = self.socket(zmq.DEALER)
+        server.identity = b'IDENT'
+        client = self.socket(zmq.DEALER)
+        self.sockets.extend([server, client])
+        try:
+            server.curve_server = True
+        except zmq.ZMQError as e:
+            # will raise EINVAL if not linked against libsodium
+            if e.errno == zmq.EINVAL:
+                raise SkipTest("CURVE unsupported")
+        
+        server_public, server_secret = zmq.curve_keypair()
+        client_public, client_secret = zmq.curve_keypair()
+        
+        server.curve_secretkey = server_secret
+        server.curve_publickey = server_public
+        client.curve_serverkey = server_public
+        client.curve_publickey = client_public
+        client.curve_secretkey = client_secret
+        
+        self.assertEqual(server.mechanism, zmq.CURVE)
+        self.assertEqual(client.mechanism, zmq.CURVE)
+        
+        self.assertEqual(server.get(zmq.CURVE_SERVER), True)
+        self.assertEqual(client.get(zmq.CURVE_SERVER), False)
+        
+        self.start_zap()
+        
+        iface = 'tcp://127.0.0.1'
+        port = server.bind_to_random_port(iface)
+        client.connect("%s:%i" % (iface, port))
+        self.bounce(server, client)
+        self.stop_zap()
+        
diff --git a/zmq/tests/test_socket.py b/zmq/tests/test_socket.py
new file mode 100644
index 0000000..13bfed7
--- /dev/null
+++ b/zmq/tests/test_socket.py
@@ -0,0 +1,451 @@
+# -*- coding: utf8 -*-
+# Copyright (C) PyZMQ Developers
+# Distributed under the terms of the Modified BSD License.
+
+import time
+import warnings
+
+import zmq
+from zmq.tests import (
+    BaseZMQTestCase, SkipTest, have_gevent, GreenTest, skip_pypy, skip_if
+)
+from zmq.utils.strtypes import bytes, unicode
+
+
+class TestSocket(BaseZMQTestCase):
+
+    def test_create(self):
+        ctx = self.Context()
+        s = ctx.socket(zmq.PUB)
+        # Superluminal protocol not yet implemented
+        self.assertRaisesErrno(zmq.EPROTONOSUPPORT, s.bind, 'ftl://a')
+        self.assertRaisesErrno(zmq.EPROTONOSUPPORT, s.connect, 'ftl://a')
+        self.assertRaisesErrno(zmq.EINVAL, s.bind, 'tcp://')
+        s.close()
+        del ctx
+    
+    def test_context_manager(self):
+        url = 'inproc://a'
+        with self.Context() as ctx:
+            with ctx.socket(zmq.PUSH) as a:
+                a.bind(url)
+                with ctx.socket(zmq.PULL) as b:
+                    b.connect(url)
+                    msg = b'hi'
+                    a.send(msg)
+                    rcvd = self.recv(b)
+                    self.assertEqual(rcvd, msg)
+                self.assertEqual(b.closed, True)
+            self.assertEqual(a.closed, True)
+        self.assertEqual(ctx.closed, True)
+    
+    def test_dir(self):
+        ctx = self.Context()
+        s = ctx.socket(zmq.PUB)
+        self.assertTrue('send' in dir(s))
+        self.assertTrue('IDENTITY' in dir(s))
+        self.assertTrue('AFFINITY' in dir(s))
+        self.assertTrue('FD' in dir(s))
+        s.close()
+        ctx.term()
+
+    def test_bind_unicode(self):
+        s = self.socket(zmq.PUB)
+        p = s.bind_to_random_port(unicode("tcp://*"))
+
+    def test_connect_unicode(self):
+        s = self.socket(zmq.PUB)
+        s.connect(unicode("tcp://127.0.0.1:5555"))
+
+    def test_bind_to_random_port(self):
+        # Check that bind_to_random_port do not hide usefull exception
+        ctx = self.Context()
+        c = ctx.socket(zmq.PUB)
+        # Invalid format
+        try:
+            c.bind_to_random_port('tcp:*')
+        except zmq.ZMQError as e:
+            self.assertEqual(e.errno, zmq.EINVAL)
+        # Invalid protocol
+        try:
+            c.bind_to_random_port('rand://*')
+        except zmq.ZMQError as e:
+            self.assertEqual(e.errno, zmq.EPROTONOSUPPORT)
+
+    def test_identity(self):
+        s = self.context.socket(zmq.PULL)
+        self.sockets.append(s)
+        ident = b'identity\0\0'
+        s.identity = ident
+        self.assertEqual(s.get(zmq.IDENTITY), ident)
+
+    def test_unicode_sockopts(self):
+        """test setting/getting sockopts with unicode strings"""
+        topic = "tést"
+        if str is not unicode:
+            topic = topic.decode('utf8')
+        p,s = self.create_bound_pair(zmq.PUB, zmq.SUB)
+        self.assertEqual(s.send_unicode, s.send_unicode)
+        self.assertEqual(p.recv_unicode, p.recv_unicode)
+        self.assertRaises(TypeError, s.setsockopt, zmq.SUBSCRIBE, topic)
+        self.assertRaises(TypeError, s.setsockopt, zmq.IDENTITY, topic)
+        s.setsockopt_unicode(zmq.IDENTITY, topic, 'utf16')
+        self.assertRaises(TypeError, s.setsockopt, zmq.AFFINITY, topic)
+        s.setsockopt_unicode(zmq.SUBSCRIBE, topic)
+        self.assertRaises(TypeError, s.getsockopt_unicode, zmq.AFFINITY)
+        self.assertRaisesErrno(zmq.EINVAL, s.getsockopt_unicode, zmq.SUBSCRIBE)
+        
+        identb = s.getsockopt(zmq.IDENTITY)
+        identu = identb.decode('utf16')
+        identu2 = s.getsockopt_unicode(zmq.IDENTITY, 'utf16')
+        self.assertEqual(identu, identu2)
+        time.sleep(0.1) # wait for connection/subscription
+        p.send_unicode(topic,zmq.SNDMORE)
+        p.send_unicode(topic*2, encoding='latin-1')
+        self.assertEqual(topic, s.recv_unicode())
+        self.assertEqual(topic*2, s.recv_unicode(encoding='latin-1'))
+    
+    def test_int_sockopts(self):
+        "test integer sockopts"
+        v = zmq.zmq_version_info()
+        if v < (3,0):
+            default_hwm = 0
+        else:
+            default_hwm = 1000
+        p,s = self.create_bound_pair(zmq.PUB, zmq.SUB)
+        p.setsockopt(zmq.LINGER, 0)
+        self.assertEqual(p.getsockopt(zmq.LINGER), 0)
+        p.setsockopt(zmq.LINGER, -1)
+        self.assertEqual(p.getsockopt(zmq.LINGER), -1)
+        self.assertEqual(p.hwm, default_hwm)
+        p.hwm = 11
+        self.assertEqual(p.hwm, 11)
+        # p.setsockopt(zmq.EVENTS, zmq.POLLIN)
+        self.assertEqual(p.getsockopt(zmq.EVENTS), zmq.POLLOUT)
+        self.assertRaisesErrno(zmq.EINVAL, p.setsockopt,zmq.EVENTS, 2**7-1)
+        self.assertEqual(p.getsockopt(zmq.TYPE), p.socket_type)
+        self.assertEqual(p.getsockopt(zmq.TYPE), zmq.PUB)
+        self.assertEqual(s.getsockopt(zmq.TYPE), s.socket_type)
+        self.assertEqual(s.getsockopt(zmq.TYPE), zmq.SUB)
+        
+        # check for overflow / wrong type:
+        errors = []
+        backref = {}
+        constants = zmq.constants
+        for name in constants.__all__:
+            value = getattr(constants, name)
+            if isinstance(value, int):
+                backref[value] = name
+        for opt in zmq.constants.int_sockopts.union(zmq.constants.int64_sockopts):
+            sopt = backref[opt]
+            if sopt.startswith((
+                'ROUTER', 'XPUB', 'TCP', 'FAIL',
+                'REQ_', 'CURVE_', 'PROBE_ROUTER',
+                'IPC_FILTER', 'GSSAPI',
+                )):
+                # some sockopts are write-only
+                continue
+            try:
+                n = p.getsockopt(opt)
+            except zmq.ZMQError as e:
+                errors.append("getsockopt(zmq.%s) raised '%s'."%(sopt, e))
+            else:
+                if n > 2**31:
+                    errors.append("getsockopt(zmq.%s) returned a ridiculous value."
+                                    " It is probably the wrong type."%sopt)
+        if errors:
+            self.fail('\n'.join([''] + errors))
+    
+    def test_bad_sockopts(self):
+        """Test that appropriate errors are raised on bad socket options"""
+        s = self.context.socket(zmq.PUB)
+        self.sockets.append(s)
+        s.setsockopt(zmq.LINGER, 0)
+        # unrecognized int sockopts pass through to libzmq, and should raise EINVAL
+        self.assertRaisesErrno(zmq.EINVAL, s.setsockopt, 9999, 5)
+        self.assertRaisesErrno(zmq.EINVAL, s.getsockopt, 9999)
+        # but only int sockopts are allowed through this way, otherwise raise a TypeError
+        self.assertRaises(TypeError, s.setsockopt, 9999, b"5")
+        # some sockopts are valid in general, but not on every socket:
+        self.assertRaisesErrno(zmq.EINVAL, s.setsockopt, zmq.SUBSCRIBE, b'hi')
+    
+    def test_sockopt_roundtrip(self):
+        "test set/getsockopt roundtrip."
+        p = self.context.socket(zmq.PUB)
+        self.sockets.append(p)
+        self.assertEqual(p.getsockopt(zmq.LINGER), -1)
+        p.setsockopt(zmq.LINGER, 11)
+        self.assertEqual(p.getsockopt(zmq.LINGER), 11)
+    
+    def test_send_unicode(self):
+        "test sending unicode objects"
+        a,b = self.create_bound_pair(zmq.PAIR, zmq.PAIR)
+        self.sockets.extend([a,b])
+        u = "çπ§"
+        if str is not unicode:
+            u = u.decode('utf8')
+        self.assertRaises(TypeError, a.send, u,copy=False)
+        self.assertRaises(TypeError, a.send, u,copy=True)
+        a.send_unicode(u)
+        s = b.recv()
+        self.assertEqual(s,u.encode('utf8'))
+        self.assertEqual(s.decode('utf8'),u)
+        a.send_unicode(u,encoding='utf16')
+        s = b.recv_unicode(encoding='utf16')
+        self.assertEqual(s,u)
+    
+    @skip_pypy
+    def test_tracker(self):
+        "test the MessageTracker object for tracking when zmq is done with a buffer"
+        addr = 'tcp://127.0.0.1'
+        a = self.context.socket(zmq.PUB)
+        port = a.bind_to_random_port(addr)
+        a.close()
+        iface = "%s:%i"%(addr,port)
+        a = self.context.socket(zmq.PAIR)
+        # a.setsockopt(zmq.IDENTITY, b"a")
+        b = self.context.socket(zmq.PAIR)
+        self.sockets.extend([a,b])
+        a.connect(iface)
+        time.sleep(0.1)
+        p1 = a.send(b'something', copy=False, track=True)
+        self.assertTrue(isinstance(p1, zmq.MessageTracker))
+        self.assertFalse(p1.done)
+        p2 = a.send_multipart([b'something', b'else'], copy=False, track=True)
+        self.assert_(isinstance(p2, zmq.MessageTracker))
+        self.assertEqual(p2.done, False)
+        self.assertEqual(p1.done, False)
+
+        b.bind(iface)
+        msg = b.recv_multipart()
+        for i in range(10):
+            if p1.done:
+                break
+            time.sleep(0.1)
+        self.assertEqual(p1.done, True)
+        self.assertEqual(msg, [b'something'])
+        msg = b.recv_multipart()
+        for i in range(10):
+            if p2.done:
+                break
+            time.sleep(0.1)
+        self.assertEqual(p2.done, True)
+        self.assertEqual(msg, [b'something', b'else'])
+        m = zmq.Frame(b"again", track=True)
+        self.assertEqual(m.tracker.done, False)
+        p1 = a.send(m, copy=False)
+        p2 = a.send(m, copy=False)
+        self.assertEqual(m.tracker.done, False)
+        self.assertEqual(p1.done, False)
+        self.assertEqual(p2.done, False)
+        msg = b.recv_multipart()
+        self.assertEqual(m.tracker.done, False)
+        self.assertEqual(msg, [b'again'])
+        msg = b.recv_multipart()
+        self.assertEqual(m.tracker.done, False)
+        self.assertEqual(msg, [b'again'])
+        self.assertEqual(p1.done, False)
+        self.assertEqual(p2.done, False)
+        pm = m.tracker
+        del m
+        for i in range(10):
+            if p1.done:
+                break
+            time.sleep(0.1)
+        self.assertEqual(p1.done, True)
+        self.assertEqual(p2.done, True)
+        m = zmq.Frame(b'something', track=False)
+        self.assertRaises(ValueError, a.send, m, copy=False, track=True)
+        
+
+    def test_close(self):
+        ctx = self.Context()
+        s = ctx.socket(zmq.PUB)
+        s.close()
+        self.assertRaisesErrno(zmq.ENOTSOCK, s.bind, b'')
+        self.assertRaisesErrno(zmq.ENOTSOCK, s.connect, b'')
+        self.assertRaisesErrno(zmq.ENOTSOCK, s.setsockopt, zmq.SUBSCRIBE, b'')
+        self.assertRaisesErrno(zmq.ENOTSOCK, s.send, b'asdf')
+        self.assertRaisesErrno(zmq.ENOTSOCK, s.recv)
+        del ctx
+    
+    def test_attr(self):
+        """set setting/getting sockopts as attributes"""
+        s = self.context.socket(zmq.DEALER)
+        self.sockets.append(s)
+        linger = 10
+        s.linger = linger
+        self.assertEqual(linger, s.linger)
+        self.assertEqual(linger, s.getsockopt(zmq.LINGER))
+        self.assertEqual(s.fd, s.getsockopt(zmq.FD))
+    
+    def test_bad_attr(self):
+        s = self.context.socket(zmq.DEALER)
+        self.sockets.append(s)
+        try:
+            s.apple='foo'
+        except AttributeError:
+            pass
+        else:
+            self.fail("bad setattr should have raised AttributeError")
+        try:
+            s.apple
+        except AttributeError:
+            pass
+        else:
+            self.fail("bad getattr should have raised AttributeError")
+
+    def test_subclass(self):
+        """subclasses can assign attributes"""
+        class S(zmq.Socket):
+            a = None
+            def __init__(self, *a, **kw):
+                self.a=-1
+                super(S, self).__init__(*a, **kw)
+        
+        s = S(self.context, zmq.REP)
+        self.sockets.append(s)
+        self.assertEqual(s.a, -1)
+        s.a=1
+        self.assertEqual(s.a, 1)
+        a=s.a
+        self.assertEqual(a, 1)
+    
+    def test_recv_multipart(self):
+        a,b = self.create_bound_pair()
+        msg = b'hi'
+        for i in range(3):
+            a.send(msg)
+        time.sleep(0.1)
+        for i in range(3):
+            self.assertEqual(b.recv_multipart(), [msg])
+    
+    def test_close_after_destroy(self):
+        """s.close() after ctx.destroy() should be fine"""
+        ctx = self.Context()
+        s = ctx.socket(zmq.REP)
+        ctx.destroy()
+        # reaper is not instantaneous
+        time.sleep(1e-2)
+        s.close()
+        self.assertTrue(s.closed)
+    
+    def test_poll(self):
+        a,b = self.create_bound_pair()
+        tic = time.time()
+        evt = a.poll(50)
+        self.assertEqual(evt, 0)
+        evt = a.poll(50, zmq.POLLOUT)
+        self.assertEqual(evt, zmq.POLLOUT)
+        msg = b'hi'
+        a.send(msg)
+        evt = b.poll(50)
+        self.assertEqual(evt, zmq.POLLIN)
+        msg2 = self.recv(b)
+        evt = b.poll(50)
+        self.assertEqual(evt, 0)
+        self.assertEqual(msg2, msg)
+    
+    def test_ipc_path_max_length(self):
+        """IPC_PATH_MAX_LEN is a sensible value"""
+        if zmq.IPC_PATH_MAX_LEN == 0:
+            raise SkipTest("IPC_PATH_MAX_LEN undefined")
+        
+        msg = "Surprising value for IPC_PATH_MAX_LEN: %s" % zmq.IPC_PATH_MAX_LEN
+        self.assertTrue(zmq.IPC_PATH_MAX_LEN > 30, msg)
+        self.assertTrue(zmq.IPC_PATH_MAX_LEN < 1025, msg)
+
+    def test_ipc_path_max_length_msg(self):
+        if zmq.IPC_PATH_MAX_LEN == 0:
+            raise SkipTest("IPC_PATH_MAX_LEN undefined")
+        
+        s = self.context.socket(zmq.PUB)
+        self.sockets.append(s)
+        try:
+            s.bind('ipc://{0}'.format('a' * (zmq.IPC_PATH_MAX_LEN + 1)))
+        except zmq.ZMQError as e:
+            self.assertTrue(str(zmq.IPC_PATH_MAX_LEN) in e.strerror)
+    
+    def test_hwm(self):
+        zmq3 = zmq.zmq_version_info()[0] >= 3
+        for stype in (zmq.PUB, zmq.ROUTER, zmq.SUB, zmq.REQ, zmq.DEALER):
+            s = self.context.socket(stype)
+            s.hwm = 100
+            self.assertEqual(s.hwm, 100)
+            if zmq3:
+                try:
+                    self.assertEqual(s.sndhwm, 100)
+                except AttributeError:
+                    pass
+                try:
+                    self.assertEqual(s.rcvhwm, 100)
+                except AttributeError:
+                    pass
+            s.close()
+    
+    def test_shadow(self):
+        p = self.socket(zmq.PUSH)
+        p.bind("tcp://127.0.0.1:5555")
+        p2 = zmq.Socket.shadow(p.underlying)
+        self.assertEqual(p.underlying, p2.underlying)
+        s = self.socket(zmq.PULL)
+        s2 = zmq.Socket.shadow(s.underlying)
+        self.assertNotEqual(s.underlying, p.underlying)
+        self.assertEqual(s.underlying, s2.underlying)
+        s2.connect("tcp://127.0.0.1:5555")
+        sent = b'hi'
+        p2.send(sent)
+        rcvd = self.recv(s2)
+        self.assertEqual(rcvd, sent)
+    
+    def test_shadow_pyczmq(self):
+        try:
+            from pyczmq import zctx, zsocket
+        except Exception:
+            raise SkipTest("Requires pyczmq")
+        
+        ctx = zctx.new()
+        ca = zsocket.new(ctx, zmq.PUSH)
+        cb = zsocket.new(ctx, zmq.PULL)
+        a = zmq.Socket.shadow(ca)
+        b = zmq.Socket.shadow(cb)
+        a.bind("inproc://a")
+        b.connect("inproc://a")
+        a.send(b'hi')
+        rcvd = self.recv(b)
+        self.assertEqual(rcvd, b'hi')
+
+
+if have_gevent:
+    import gevent
+    
+    class TestSocketGreen(GreenTest, TestSocket):
+        test_bad_attr = GreenTest.skip_green
+        test_close_after_destroy = GreenTest.skip_green
+        
+        def test_timeout(self):
+            a,b = self.create_bound_pair()
+            g = gevent.spawn_later(0.5, lambda: a.send(b'hi'))
+            timeout = gevent.Timeout(0.1)
+            timeout.start()
+            self.assertRaises(gevent.Timeout, b.recv)
+            g.kill()
+        
+        @skip_if(not hasattr(zmq, 'RCVTIMEO'))
+        def test_warn_set_timeo(self):
+            s = self.context.socket(zmq.REQ)
+            with warnings.catch_warnings(record=True) as w:
+                s.rcvtimeo = 5
+            s.close()
+            self.assertEqual(len(w), 1)
+            self.assertEqual(w[0].category, UserWarning)
+            
+
+        @skip_if(not hasattr(zmq, 'SNDTIMEO'))
+        def test_warn_get_timeo(self):
+            s = self.context.socket(zmq.REQ)
+            with warnings.catch_warnings(record=True) as w:
+                s.sndtimeo
+            s.close()
+            self.assertEqual(len(w), 1)
+            self.assertEqual(w[0].category, UserWarning)
diff --git a/zmq/tests/test_stopwatch.py b/zmq/tests/test_stopwatch.py
new file mode 100644
index 0000000..49fb79f
--- /dev/null
+++ b/zmq/tests/test_stopwatch.py
@@ -0,0 +1,42 @@
+# -*- coding: utf8 -*-
+# Copyright (C) PyZMQ Developers
+# Distributed under the terms of the Modified BSD License.
+
+
+import sys
+import time
+
+from unittest import TestCase
+
+from zmq import Stopwatch, ZMQError
+
+if sys.version_info[0] >= 3:
+    long = int
+
+class TestStopWatch(TestCase):
+    
+    def test_stop_long(self):
+        """Ensure stop returns a long int."""
+        watch = Stopwatch()
+        watch.start()
+        us = watch.stop()
+        self.assertTrue(isinstance(us, long))
+        
+    def test_stop_microseconds(self):
+        """Test that stop/sleep have right units."""
+        watch = Stopwatch()
+        watch.start()
+        tic = time.time()
+        watch.sleep(1)
+        us = watch.stop()
+        toc = time.time()
+        self.assertAlmostEqual(us/1e6,(toc-tic),places=0)
+    
+    def test_double_stop(self):
+        """Test error raised on multiple calls to stop."""
+        watch = Stopwatch()
+        watch.start()
+        watch.stop()
+        self.assertRaises(ZMQError, watch.stop)
+        self.assertRaises(ZMQError, watch.stop)
+    
diff --git a/zmq/tests/test_version.py b/zmq/tests/test_version.py
new file mode 100644
index 0000000..6ebebf3
--- /dev/null
+++ b/zmq/tests/test_version.py
@@ -0,0 +1,44 @@
+# Copyright (C) PyZMQ Developers
+# Distributed under the terms of the Modified BSD License.
+
+
+from unittest import TestCase
+import zmq
+from zmq.sugar import version
+
+
+class TestVersion(TestCase):
+
+    def test_pyzmq_version(self):
+        vs = zmq.pyzmq_version()
+        vs2 = zmq.__version__
+        self.assertTrue(isinstance(vs, str))
+        if zmq.__revision__:
+            self.assertEqual(vs, '@'.join(vs2, zmq.__revision__))
+        else:
+            self.assertEqual(vs, vs2)
+        if version.VERSION_EXTRA:
+            self.assertTrue(version.VERSION_EXTRA in vs)
+            self.assertTrue(version.VERSION_EXTRA in vs2)
+
+    def test_pyzmq_version_info(self):
+        info = zmq.pyzmq_version_info()
+        self.assertTrue(isinstance(info, tuple))
+        for n in info[:3]:
+            self.assertTrue(isinstance(n, int))
+        if version.VERSION_EXTRA:
+            self.assertEqual(len(info), 4)
+            self.assertEqual(info[-1], float('inf'))
+        else:
+            self.assertEqual(len(info), 3)
+
+    def test_zmq_version_info(self):
+        info = zmq.zmq_version_info()
+        self.assertTrue(isinstance(info, tuple))
+        for n in info[:3]:
+            self.assertTrue(isinstance(n, int))
+
+    def test_zmq_version(self):
+        v = zmq.zmq_version()
+        self.assertTrue(isinstance(v, str))
+
diff --git a/zmq/tests/test_win32_shim.py b/zmq/tests/test_win32_shim.py
new file mode 100644
index 0000000..55657bd
--- /dev/null
+++ b/zmq/tests/test_win32_shim.py
@@ -0,0 +1,56 @@
+from __future__ import print_function
+
+import os
+
+from functools import wraps
+from zmq.tests import BaseZMQTestCase
+from zmq.utils.win32 import allow_interrupt
+
+
+def count_calls(f):
+    @wraps(f)
+    def _(*args, **kwds):
+        try:
+            return f(*args, **kwds)
+        finally:
+            _.__calls__ += 1
+    _.__calls__ = 0
+    return _
+
+
+class TestWindowsConsoleControlHandler(BaseZMQTestCase):
+
+    def test_handler(self):
+        @count_calls
+        def interrupt_polling():
+            print('Caught CTRL-C!')
+
+        if os.name == 'nt':
+            from ctypes import windll
+            from ctypes.wintypes import BOOL, DWORD
+
+            kernel32 = windll.LoadLibrary('kernel32')
+
+            # <http://msdn.microsoft.com/en-us/library/ms683155.aspx>
+            GenerateConsoleCtrlEvent = kernel32.GenerateConsoleCtrlEvent
+            GenerateConsoleCtrlEvent.argtypes = (DWORD, DWORD)
+            GenerateConsoleCtrlEvent.restype = BOOL
+
+            try:
+                # Simulate CTRL-C event while handler is active.
+                with allow_interrupt(interrupt_polling):
+                    result = GenerateConsoleCtrlEvent(0, 0)
+                    if result == 0:
+                        raise WindowsError
+            except KeyboardInterrupt:
+                pass
+            else:
+                self.fail('Expecting `KeyboardInterrupt` exception!')
+
+            # Make sure our handler was called.
+            self.assertEqual(interrupt_polling.__calls__, 1)
+        else:
+            # On non-Windows systems, this utility is just a no-op!
+            with allow_interrupt(interrupt_polling):
+                pass
+            self.assertEqual(interrupt_polling.__calls__, 0)
diff --git a/zmq/tests/test_z85.py b/zmq/tests/test_z85.py
new file mode 100644
index 0000000..8a73cb4
--- /dev/null
+++ b/zmq/tests/test_z85.py
@@ -0,0 +1,63 @@
+# -*- coding: utf8 -*-
+"""Test Z85 encoding
+
+confirm values and roundtrip with test values from the reference implementation.
+"""
+
+# Copyright (C) PyZMQ Developers
+# Distributed under the terms of the Modified BSD License.
+
+from unittest import TestCase
+from zmq.utils import z85
+
+
+class TestZ85(TestCase):
+    
+    def test_client_public(self):
+        client_public = \
+            b"\xBB\x88\x47\x1D\x65\xE2\x65\x9B" \
+            b"\x30\xC5\x5A\x53\x21\xCE\xBB\x5A" \
+            b"\xAB\x2B\x70\xA3\x98\x64\x5C\x26" \
+            b"\xDC\xA2\xB2\xFC\xB4\x3F\xC5\x18"
+        encoded = z85.encode(client_public)
+        
+        self.assertEqual(encoded, b"Yne@$w-vo<fVvi]a<NY6T1ed:M$fCG*[IaLV{hID")
+        decoded = z85.decode(encoded)
+        self.assertEqual(decoded, client_public)
+    
+    def test_client_secret(self):
+        client_secret = \
+            b"\x7B\xB8\x64\xB4\x89\xAF\xA3\x67" \
+            b"\x1F\xBE\x69\x10\x1F\x94\xB3\x89" \
+            b"\x72\xF2\x48\x16\xDF\xB0\x1B\x51" \
+            b"\x65\x6B\x3F\xEC\x8D\xFD\x08\x88"
+        encoded = z85.encode(client_secret)
+        
+        self.assertEqual(encoded, b"D:)Q[IlAW!ahhC2ac:9*A}h:p?([4%wOTJ%JR%cs")
+        decoded = z85.decode(encoded)
+        self.assertEqual(decoded, client_secret)
+
+    def test_server_public(self):
+        server_public = \
+            b"\x54\xFC\xBA\x24\xE9\x32\x49\x96" \
+            b"\x93\x16\xFB\x61\x7C\x87\x2B\xB0" \
+            b"\xC1\xD1\xFF\x14\x80\x04\x27\xC5" \
+            b"\x94\xCB\xFA\xCF\x1B\xC2\xD6\x52"
+        encoded = z85.encode(server_public)
+        
+        self.assertEqual(encoded, b"rq:rM>}U?@Lns47E1%kR.o@n%FcmmsL/@{H8]yf7")
+        decoded = z85.decode(encoded)
+        self.assertEqual(decoded, server_public)
+    
+    def test_server_secret(self):
+        server_secret = \
+            b"\x8E\x0B\xDD\x69\x76\x28\xB9\x1D" \
+            b"\x8F\x24\x55\x87\xEE\x95\xC5\xB0" \
+            b"\x4D\x48\x96\x3F\x79\x25\x98\x77" \
+            b"\xB4\x9C\xD9\x06\x3A\xEA\xD3\xB7"
+        encoded = z85.encode(server_secret)
+        
+        self.assertEqual(encoded, b"JTKVSB%%)wK0E.X)V>+}o?pNmC{O&4W4b!Ni{Lh6")
+        decoded = z85.decode(encoded)
+        self.assertEqual(decoded, server_secret)
+
diff --git a/zmq/tests/test_zmqstream.py b/zmq/tests/test_zmqstream.py
new file mode 100644
index 0000000..cdb3a17
--- /dev/null
+++ b/zmq/tests/test_zmqstream.py
@@ -0,0 +1,34 @@
+# -*- coding: utf8 -*-
+# Copyright (C) PyZMQ Developers
+# Distributed under the terms of the Modified BSD License.
+
+
+import sys
+import time
+
+from unittest import TestCase
+
+import zmq
+from zmq.eventloop import ioloop, zmqstream
+
+class TestZMQStream(TestCase):
+    
+    def setUp(self):
+        self.context = zmq.Context()
+        self.socket = self.context.socket(zmq.REP)
+        self.loop = ioloop.IOLoop.instance()
+        self.stream = zmqstream.ZMQStream(self.socket)
+    
+    def tearDown(self):
+        self.socket.close()
+        self.context.term()
+    
+    def test_callable_check(self):
+        """Ensure callable check works (py3k)."""
+        
+        self.stream.on_send(lambda *args: None)
+        self.stream.on_recv(lambda *args: None)
+        self.assertRaises(AssertionError, self.stream.on_recv, 1)
+        self.assertRaises(AssertionError, self.stream.on_send, 1)
+        self.assertRaises(AssertionError, self.stream.on_recv, zmq)
+        
diff --git a/zmq/utils/__init__.py b/zmq/utils/__init__.py
new file mode 100644
index 0000000..e69de29
--- /dev/null
+++ b/zmq/utils/__init__.py
diff --git a/zmq/utils/buffers.pxd b/zmq/utils/buffers.pxd
new file mode 100644
index 0000000..998aa55
--- /dev/null
+++ b/zmq/utils/buffers.pxd
@@ -0,0 +1,313 @@
+"""Python version-independent methods for C/Python buffers.
+
+This file was copied and adapted from mpi4py.
+
+Authors
+-------
+* MinRK
+"""
+
+#-----------------------------------------------------------------------------
+#  Copyright (c) 2010 Lisandro Dalcin
+#  All rights reserved.
+#  Used under BSD License: http://www.opensource.org/licenses/bsd-license.php
+#
+#  Retrieval:
+#  Jul 23, 2010 18:00 PST (r539)
+#  http://code.google.com/p/mpi4py/source/browse/trunk/src/MPI/asbuffer.pxi
+#
+#  Modifications from original:
+#  Copyright (c) 2010-2012 Brian Granger, Min Ragan-Kelley
+#
+#  Distributed under the terms of the New BSD License.  The full license is in
+#  the file COPYING.BSD, distributed as part of this software.
+#-----------------------------------------------------------------------------
+
+
+#-----------------------------------------------------------------------------
+# Python includes.
+#-----------------------------------------------------------------------------
+
+# get version-independent aliases:
+cdef extern from "pyversion_compat.h":
+    pass
+
+# Python 3 buffer interface (PEP 3118)
+cdef extern from "Python.h":
+    int PY_MAJOR_VERSION
+    int PY_MINOR_VERSION
+    ctypedef int Py_ssize_t
+    ctypedef struct PyMemoryViewObject:
+        pass
+    ctypedef struct Py_buffer:
+        void *buf
+        Py_ssize_t len
+        int readonly
+        char *format
+        int ndim
+        Py_ssize_t *shape
+        Py_ssize_t *strides
+        Py_ssize_t *suboffsets
+        Py_ssize_t itemsize
+        void *internal
+    cdef enum:
+        PyBUF_SIMPLE
+        PyBUF_WRITABLE
+        PyBUF_FORMAT
+        PyBUF_ANY_CONTIGUOUS
+    int  PyObject_CheckBuffer(object)
+    int  PyObject_GetBuffer(object, Py_buffer *, int) except -1
+    void PyBuffer_Release(Py_buffer *)
+    
+    int PyBuffer_FillInfo(Py_buffer *view, object obj, void *buf,
+                Py_ssize_t len, int readonly, int infoflags) except -1
+    object PyMemoryView_FromBuffer(Py_buffer *info)
+    
+    object PyMemoryView_FromObject(object)
+
+# Python 2 buffer interface (legacy)
+cdef extern from "Python.h":
+    ctypedef void const_void "const void"
+    Py_ssize_t Py_END_OF_BUFFER
+    int PyObject_CheckReadBuffer(object)
+    int PyObject_AsReadBuffer (object, const_void **, Py_ssize_t *) except -1
+    int PyObject_AsWriteBuffer(object, void **, Py_ssize_t *) except -1
+    
+    object PyBuffer_FromMemory(void *ptr, Py_ssize_t s)
+    object PyBuffer_FromReadWriteMemory(void *ptr, Py_ssize_t s)
+
+    object PyBuffer_FromObject(object, Py_ssize_t offset, Py_ssize_t size)
+    object PyBuffer_FromReadWriteObject(object, Py_ssize_t offset, Py_ssize_t size)
+
+
+#-----------------------------------------------------------------------------
+# asbuffer: C buffer from python object
+#-----------------------------------------------------------------------------
+
+
+cdef inline int memoryview_available():
+    return PY_MAJOR_VERSION >= 3 or (PY_MAJOR_VERSION >=2 and PY_MINOR_VERSION >= 7)
+
+cdef inline int oldstyle_available():
+    return PY_MAJOR_VERSION < 3
+
+
+cdef inline int check_buffer(object ob):
+    """Version independent check for whether an object is a buffer.
+    
+    Parameters
+    ----------
+    object : object
+        Any Python object
+
+    Returns
+    -------
+    int : 0 if no buffer interface, 3 if newstyle buffer interface, 2 if oldstyle.
+    """
+    if PyObject_CheckBuffer(ob):
+        return 3
+    if oldstyle_available():
+        return PyObject_CheckReadBuffer(ob) and 2
+    return 0
+
+
+cdef inline object asbuffer(object ob, int writable, int format,
+                            void **base, Py_ssize_t *size,
+                            Py_ssize_t *itemsize):
+    """Turn an object into a C buffer in a Python version-independent way.
+    
+    Parameters
+    ----------
+    ob : object
+        The object to be turned into a buffer.
+        Must provide a Python Buffer interface
+    writable : int
+        Whether the resulting buffer should be allowed to write
+        to the object.
+    format : int
+        The format of the buffer.  See Python buffer docs.
+    base : void **
+        The pointer that will be used to store the resulting C buffer.
+    size : Py_ssize_t *
+        The size of the buffer(s).
+    itemsize : Py_ssize_t *
+        The size of an item, if the buffer is non-contiguous.
+    
+    Returns
+    -------
+    An object describing the buffer format. Generally a str, such as 'B'.
+    """
+
+    cdef void *bptr = NULL
+    cdef Py_ssize_t blen = 0, bitemlen = 0
+    cdef Py_buffer view
+    cdef int flags = PyBUF_SIMPLE
+    cdef int mode = 0
+    
+    bfmt = None
+
+    mode = check_buffer(ob)
+    if mode == 0:
+        raise TypeError("%r does not provide a buffer interface."%ob)
+
+    if mode == 3:
+        flags = PyBUF_ANY_CONTIGUOUS
+        if writable:
+            flags |= PyBUF_WRITABLE
+        if format:
+            flags |= PyBUF_FORMAT
+        PyObject_GetBuffer(ob, &view, flags)
+        bptr = view.buf
+        blen = view.len
+        if format:
+            if view.format != NULL:
+                bfmt = view.format
+                bitemlen = view.itemsize
+        PyBuffer_Release(&view)
+    else: # oldstyle
+        if writable:
+            PyObject_AsWriteBuffer(ob, &bptr, &blen)
+        else:
+            PyObject_AsReadBuffer(ob, <const_void **>&bptr, &blen)
+        if format:
+            try: # numpy.ndarray
+                dtype = ob.dtype
+                bfmt = dtype.char
+                bitemlen = dtype.itemsize
+            except AttributeError:
+                try: # array.array
+                    bfmt = ob.typecode
+                    bitemlen = ob.itemsize
+                except AttributeError:
+                    if isinstance(ob, bytes):
+                        bfmt = b"B"
+                        bitemlen = 1
+                    else:
+                        # nothing found
+                        bfmt = None
+                        bitemlen = 0
+    if base: base[0] = <void *>bptr
+    if size: size[0] = <Py_ssize_t>blen
+    if itemsize: itemsize[0] = <Py_ssize_t>bitemlen
+    
+    if PY_MAJOR_VERSION >= 3 and bfmt is not None:
+        return bfmt.decode('ascii')
+    return bfmt
+
+
+cdef inline object asbuffer_r(object ob, void **base, Py_ssize_t *size):
+    """Wrapper for standard calls to asbuffer with a readonly buffer."""
+    asbuffer(ob, 0, 0, base, size, NULL)
+    return ob
+
+
+cdef inline object asbuffer_w(object ob, void **base, Py_ssize_t *size):
+    """Wrapper for standard calls to asbuffer with a writable buffer."""
+    asbuffer(ob, 1, 0, base, size, NULL)
+    return ob
+
+#------------------------------------------------------------------------------
+# frombuffer: python buffer/view from C buffer
+#------------------------------------------------------------------------------
+
+
+cdef inline object frombuffer_3(void *ptr, Py_ssize_t s, int readonly):
+    """Python 3 version of frombuffer.
+
+    This is the Python 3 model, but will work on Python >= 2.6. Currently,
+    we use it only on >= 3.0.
+    """
+    cdef Py_buffer pybuf
+    cdef Py_ssize_t *shape = [s]
+    cdef str astr=""
+    PyBuffer_FillInfo(&pybuf, astr, ptr, s, readonly, PyBUF_SIMPLE)
+    pybuf.format = "B"
+    pybuf.shape = shape
+    return PyMemoryView_FromBuffer(&pybuf)
+
+
+cdef inline object frombuffer_2(void *ptr, Py_ssize_t s, int readonly):
+    """Python 2 version of frombuffer. 
+
+    This must be used for Python <= 2.6, but we use it for all Python < 3.
+    """
+    
+    if oldstyle_available():
+        if readonly:
+            return PyBuffer_FromMemory(ptr, s)
+        else:
+            return PyBuffer_FromReadWriteMemory(ptr, s)
+    else:
+        raise NotImplementedError("Old style buffers not available.")
+
+
+cdef inline object frombuffer(void *ptr, Py_ssize_t s, int readonly):
+    """Create a Python Buffer/View of a C array. 
+    
+    Parameters
+    ----------
+    ptr : void *
+        Pointer to the array to be copied.
+    s : size_t
+        Length of the buffer.
+    readonly : int
+        whether the resulting object should be allowed to write to the buffer.
+    
+    Returns
+    -------
+    Python Buffer/View of the C buffer.
+    """
+    # oldstyle first priority for now
+    if oldstyle_available():
+        return frombuffer_2(ptr, s, readonly)
+    else:
+        return frombuffer_3(ptr, s, readonly)
+
+
+cdef inline object frombuffer_r(void *ptr, Py_ssize_t s):
+    """Wrapper for readonly view frombuffer."""
+    return frombuffer(ptr, s, 1)
+
+
+cdef inline object frombuffer_w(void *ptr, Py_ssize_t s):
+    """Wrapper for writable view frombuffer."""
+    return frombuffer(ptr, s, 0)
+
+#------------------------------------------------------------------------------
+# viewfromobject: python buffer/view from python object, refcounts intact
+# frombuffer(asbuffer(obj)) would lose track of refs
+#------------------------------------------------------------------------------
+
+cdef inline object viewfromobject(object obj, int readonly):
+    """Construct a Python Buffer/View object from another Python object.
+
+    This work in a Python version independent manner.
+    
+    Parameters
+    ----------
+    obj : object
+        The input object to be cast as a buffer
+    readonly : int
+        Whether the result should be prevented from overwriting the original.
+    
+    Returns
+    -------
+    Buffer/View of the original object.
+    """
+    if not memoryview_available():
+        if readonly:
+            return PyBuffer_FromObject(obj, 0, Py_END_OF_BUFFER)
+        else:
+            return PyBuffer_FromReadWriteObject(obj, 0, Py_END_OF_BUFFER)
+    else:
+        return PyMemoryView_FromObject(obj)
+
+
+cdef inline object viewfromobject_r(object obj):
+    """Wrapper for readonly viewfromobject."""
+    return viewfromobject(obj, 1)
+
+
+cdef inline object viewfromobject_w(object obj):
+    """Wrapper for writable viewfromobject."""
+    return viewfromobject(obj, 0)
diff --git a/zmq/utils/constant_names.py b/zmq/utils/constant_names.py
new file mode 100644
index 0000000..47da9dc
--- /dev/null
+++ b/zmq/utils/constant_names.py
@@ -0,0 +1,365 @@
+"""0MQ Constant names"""
+
+# Copyright (C) PyZMQ Developers
+# Distributed under the terms of the Modified BSD License.
+
+# dictionaries of constants new or removed in particular versions
+
+new_in = {
+    (2,2,0) : [
+        'RCVTIMEO',
+        'SNDTIMEO',
+    ],
+    (3,2,2) : [
+        # errnos
+        'EMSGSIZE',
+        'EAFNOSUPPORT',
+        'ENETUNREACH',
+        'ECONNABORTED',
+        'ECONNRESET',
+        'ENOTCONN',
+        'ETIMEDOUT',
+        'EHOSTUNREACH',
+        'ENETRESET',
+        
+        # ctx opts
+        'IO_THREADS',
+        'MAX_SOCKETS',
+        'IO_THREADS_DFLT',
+        'MAX_SOCKETS_DFLT',
+        
+        # socket opts
+        'ROUTER_BEHAVIOR',
+        'ROUTER_MANDATORY',
+        'FAIL_UNROUTABLE',
+        'TCP_KEEPALIVE',
+        'TCP_KEEPALIVE_CNT',
+        'TCP_KEEPALIVE_IDLE',
+        'TCP_KEEPALIVE_INTVL',
+        'DELAY_ATTACH_ON_CONNECT',
+        'XPUB_VERBOSE',
+        
+        # msg opts
+        'MORE',
+        
+        'EVENT_CONNECTED',
+        'EVENT_CONNECT_DELAYED',
+        'EVENT_CONNECT_RETRIED',
+        'EVENT_LISTENING',
+        'EVENT_BIND_FAILED',
+        'EVENT_ACCEPTED',
+        'EVENT_ACCEPT_FAILED',
+        'EVENT_CLOSED',
+        'EVENT_CLOSE_FAILED',
+        'EVENT_DISCONNECTED',
+        'EVENT_ALL',
+    ],
+    (4,0,0) : [
+        # socket types
+        'STREAM',
+        
+        # socket opts
+        'IMMEDIATE',
+        'ROUTER_RAW',
+        'IPV6',
+        'MECHANISM',
+        'PLAIN_SERVER',
+        'PLAIN_USERNAME',
+        'PLAIN_PASSWORD',
+        'CURVE_SERVER',
+        'CURVE_PUBLICKEY',
+        'CURVE_SECRETKEY',
+        'CURVE_SERVERKEY',
+        'PROBE_ROUTER',
+        'REQ_RELAXED',
+        'REQ_CORRELATE',
+        'CONFLATE',
+        'ZAP_DOMAIN',
+        
+        # security
+        'NULL',
+        'PLAIN',
+        'CURVE',
+        
+        # events
+        'EVENT_MONITOR_STOPPED',
+    ],
+    (4,1,0) : [
+        # ctx opts
+        'SOCKET_LIMIT',
+        'THREAD_PRIORITY',
+        'THREAD_PRIORITY_DFLT',
+        'THREAD_SCHED_POLICY',
+        'THREAD_SCHED_POLICY_DFLT',
+        
+        # socket opts
+        'ROUTER_HANDOVER',
+        'TOS',
+        'IPC_FILTER_PID',
+        'IPC_FILTER_UID',
+        'IPC_FILTER_GID',
+        'CONNECT_RID',
+        'GSSAPI_SERVER',
+        'GSSAPI_PRINCIPAL',
+        'GSSAPI_SERVICE_PRINCIPAL',
+        'GSSAPI_PLAINTEXT',
+        'HANDSHAKE_IVL',
+        'IDENTITY_FD',
+        'XPUB_NODROP',
+        'SOCKS_PROXY',
+        
+        # msg opts
+        'SRCFD',
+        'SHARED',
+        
+        # security
+        'GSSAPI',
+        
+    ],
+}
+
+
+removed_in = {
+    (3,2,2) : [
+        'UPSTREAM',
+        'DOWNSTREAM',
+        
+        'HWM',
+        'SWAP',
+        'MCAST_LOOP',
+        'RECOVERY_IVL_MSEC',
+    ]
+}
+
+# collections of zmq constant names based on their role
+# base names have no specific use
+# opt names are validated in get/set methods of various objects
+
+base_names = [
+    # base
+    'VERSION',
+    'VERSION_MAJOR',
+    'VERSION_MINOR',
+    'VERSION_PATCH',
+    'NOBLOCK',
+    'DONTWAIT',
+
+    'POLLIN',
+    'POLLOUT',
+    'POLLERR',
+    
+    'SNDMORE',
+
+    'STREAMER',
+    'FORWARDER',
+    'QUEUE',
+
+    'IO_THREADS_DFLT',
+    'MAX_SOCKETS_DFLT',
+    'POLLITEMS_DFLT',
+    'THREAD_PRIORITY_DFLT',
+    'THREAD_SCHED_POLICY_DFLT',
+
+    # socktypes
+    'PAIR',
+    'PUB',
+    'SUB',
+    'REQ',
+    'REP',
+    'DEALER',
+    'ROUTER',
+    'XREQ',
+    'XREP',
+    'PULL',
+    'PUSH',
+    'XPUB',
+    'XSUB',
+    'UPSTREAM',
+    'DOWNSTREAM',
+    'STREAM',
+
+    # events
+    'EVENT_CONNECTED',
+    'EVENT_CONNECT_DELAYED',
+    'EVENT_CONNECT_RETRIED',
+    'EVENT_LISTENING',
+    'EVENT_BIND_FAILED',
+    'EVENT_ACCEPTED',
+    'EVENT_ACCEPT_FAILED',
+    'EVENT_CLOSED',
+    'EVENT_CLOSE_FAILED',
+    'EVENT_DISCONNECTED',
+    'EVENT_ALL',
+    'EVENT_MONITOR_STOPPED',
+
+    # security
+    'NULL',
+    'PLAIN',
+    'CURVE',
+    'GSSAPI',
+
+    ## ERRNO
+    # Often used (these are alse in errno.)
+    'EAGAIN',
+    'EINVAL',
+    'EFAULT',
+    'ENOMEM',
+    'ENODEV',
+    'EMSGSIZE',
+    'EAFNOSUPPORT',
+    'ENETUNREACH',
+    'ECONNABORTED',
+    'ECONNRESET',
+    'ENOTCONN',
+    'ETIMEDOUT',
+    'EHOSTUNREACH',
+    'ENETRESET',
+
+    # For Windows compatability
+    'HAUSNUMERO',
+    'ENOTSUP',
+    'EPROTONOSUPPORT',
+    'ENOBUFS',
+    'ENETDOWN',
+    'EADDRINUSE',
+    'EADDRNOTAVAIL',
+    'ECONNREFUSED',
+    'EINPROGRESS',
+    'ENOTSOCK',
+
+    # 0MQ Native
+    'EFSM',
+    'ENOCOMPATPROTO',
+    'ETERM',
+    'EMTHREAD',
+]
+
+int64_sockopt_names = [
+    'AFFINITY',
+    'MAXMSGSIZE',
+
+    # sockopts removed in 3.0.0
+    'HWM',
+    'SWAP',
+    'MCAST_LOOP',
+    'RECOVERY_IVL_MSEC',
+]
+
+bytes_sockopt_names = [
+    'IDENTITY',
+    'SUBSCRIBE',
+    'UNSUBSCRIBE',
+    'LAST_ENDPOINT',
+    'TCP_ACCEPT_FILTER',
+
+    'PLAIN_USERNAME',
+    'PLAIN_PASSWORD',
+
+    'CURVE_PUBLICKEY',
+    'CURVE_SECRETKEY',
+    'CURVE_SERVERKEY',
+    'ZAP_DOMAIN',
+    'CONNECT_RID',
+    'GSSAPI_PRINCIPAL',
+    'GSSAPI_SERVICE_PRINCIPAL',
+    'SOCKS_PROXY',
+]
+
+fd_sockopt_names = [
+    'FD',
+    'IDENTITY_FD',
+]
+
+int_sockopt_names = [
+    # sockopts
+    'RECONNECT_IVL_MAX',
+
+    # sockopts new in 2.2.0
+    'SNDTIMEO',
+    'RCVTIMEO',
+
+    # new in 3.x
+    'SNDHWM',
+    'RCVHWM',
+    'MULTICAST_HOPS',
+    'IPV4ONLY',
+
+    'ROUTER_BEHAVIOR',
+    'TCP_KEEPALIVE',
+    'TCP_KEEPALIVE_CNT',
+    'TCP_KEEPALIVE_IDLE',
+    'TCP_KEEPALIVE_INTVL',
+    'DELAY_ATTACH_ON_CONNECT',
+    'XPUB_VERBOSE',
+
+    'EVENTS',
+    'TYPE',
+    'LINGER',
+    'RECONNECT_IVL',
+    'BACKLOG',
+    
+    'ROUTER_MANDATORY',
+    'FAIL_UNROUTABLE',
+
+    'ROUTER_RAW',
+    'IMMEDIATE',
+    'IPV6',
+    'MECHANISM',
+    'PLAIN_SERVER',
+    'CURVE_SERVER',
+    'PROBE_ROUTER',
+    'REQ_RELAXED',
+    'REQ_CORRELATE',
+    'CONFLATE',
+    'ROUTER_HANDOVER',
+    'TOS',
+    'IPC_FILTER_PID',
+    'IPC_FILTER_UID',
+    'IPC_FILTER_GID',
+    'GSSAPI_SERVER',
+    'GSSAPI_PLAINTEXT',
+    'HANDSHAKE_IVL',
+    'XPUB_NODROP',
+]
+
+switched_sockopt_names = [
+    'RATE',
+    'RECOVERY_IVL',
+    'SNDBUF',
+    'RCVBUF',
+    'RCVMORE',
+]
+
+ctx_opt_names = [
+    'IO_THREADS',
+    'MAX_SOCKETS',
+    'SOCKET_LIMIT',
+    'THREAD_PRIORITY',
+    'THREAD_SCHED_POLICY',
+]
+
+msg_opt_names = [
+    'MORE',
+    'SRCFD',
+    'SHARED',
+]
+
+from itertools import chain
+
+all_names = list(chain(
+    base_names,
+    ctx_opt_names,
+    bytes_sockopt_names,
+    fd_sockopt_names,
+    int_sockopt_names,
+    int64_sockopt_names,
+    switched_sockopt_names,
+    msg_opt_names,
+))
+
+del chain
+
+def no_prefix(name):
+    """does the given constant have a ZMQ_ prefix?"""
+    return name.startswith('E') and not name.startswith('EVENT')
+
diff --git a/zmq/utils/garbage.py b/zmq/utils/garbage.py
new file mode 100644
index 0000000..22a8977
--- /dev/null
+++ b/zmq/utils/garbage.py
@@ -0,0 +1,170 @@
+"""Garbage collection thread for representing zmq refcount of Python objects
+used in zero-copy sends.
+"""
+
+# Copyright (C) PyZMQ Developers
+# Distributed under the terms of the Modified BSD License.
+
+
+import atexit
+import struct
+
+from os import getpid
+from collections import namedtuple
+from threading import Thread, Event, Lock
+import warnings
+
+import zmq
+
+
+gcref = namedtuple('gcref', ['obj', 'event'])
+
+class GarbageCollectorThread(Thread):
+    """Thread in which garbage collection actually happens."""
+    def __init__(self, gc):
+        super(GarbageCollectorThread, self).__init__()
+        self.gc = gc
+        self.daemon = True
+        self.pid = getpid()
+        self.ready = Event()
+    
+    def run(self):
+        # detect fork at begining of the thread
+        if getpid is None or getpid() != self.pid:
+            return
+        s = self.gc.context.socket(zmq.PULL)
+        s.linger = 0
+        s.bind(self.gc.url)
+
+        self.ready.set()
+        
+        while True:
+            # detect fork
+            if getpid is None or getpid() != self.pid:
+                return
+            msg = s.recv()
+            if msg == b'DIE':
+                break
+            fmt = 'L' if len(msg) == 4 else 'Q'
+            key = struct.unpack(fmt, msg)[0]
+            tup = self.gc.refs.pop(key, None)
+            if tup and tup.event:
+                tup.event.set()
+            del tup
+        s.close()
+
+
+class GarbageCollector(object):
+    """PyZMQ Garbage Collector
+    
+    Used for representing the reference held by libzmq during zero-copy sends.
+    This object holds a dictionary, keyed by Python id,
+    of the Python objects whose memory are currently in use by zeromq.
+    
+    When zeromq is done with the memory, it sends a message on an inproc PUSH socket
+    containing the packed size_t (32 or 64-bit unsigned int),
+    which is the key in the dict.
+    When the PULL socket in the gc thread receives that message,
+    the reference is popped from the dict,
+    and any tracker events that should be signaled fire.
+    """
+    
+    refs = None
+    _context = None
+    _lock = None
+    url = "inproc://pyzmq.gc.01"
+    
+    def __init__(self, context=None):
+        super(GarbageCollector, self).__init__()
+        self.refs = {}
+        self.pid = None
+        self.thread = None
+        self._context = context
+        self._lock = Lock()
+        self._stay_down = False
+        atexit.register(self._atexit)
+    
+    @property
+    def context(self):
+        if self._context is None:
+            self._context = zmq.Context()
+        return self._context
+    
+    @context.setter
+    def context(self, ctx):
+        if self.is_alive():
+            if self.refs:
+                warnings.warn("Replacing gc context while gc is running", RuntimeWarning)
+            self.stop()
+        self._context = ctx
+    
+    def _atexit(self):
+        """atexit callback
+        
+        sets _stay_down flag so that gc doesn't try to start up again in other atexit handlers
+        """
+        self._stay_down = True
+        self.stop()
+    
+    def stop(self):
+        """stop the garbage-collection thread"""
+        if not self.is_alive():
+            return
+        push = self.context.socket(zmq.PUSH)
+        push.connect(self.url)
+        push.send(b'DIE')
+        push.close()
+        self.thread.join()
+        self.context.term()
+        self.refs.clear()
+    
+    def start(self):
+        """Start a new garbage collection thread.
+        
+        Creates a new zmq Context used for garbage collection.
+        Under most circumstances, this will only be called once per process.
+        """
+        self.pid = getpid()
+        self.refs = {}
+        self.thread = GarbageCollectorThread(self)
+        self.thread.start()
+        self.thread.ready.wait()
+    
+    def is_alive(self):
+        """Is the garbage collection thread currently running?
+        
+        Includes checks for process shutdown or fork.
+        """
+        if (getpid is None or
+            getpid() != self.pid or
+            self.thread is None or
+            not self.thread.is_alive()
+            ):
+            return False
+        return True
+    
+    def store(self, obj, event=None):
+        """store an object and (optionally) event for zero-copy"""
+        if not self.is_alive():
+            if self._stay_down:
+                return 0
+            # safely start the gc thread
+            # use lock and double check,
+            # so we don't start multiple threads
+            with self._lock:
+                if not self.is_alive():
+                    self.start()
+        tup = gcref(obj, event)
+        theid = id(tup)
+        self.refs[theid] = tup
+        return theid
+    
+    def __del__(self):
+        if not self.is_alive():
+            return
+        try:
+            self.stop()
+        except Exception as e:
+            raise (e)
+
+gc = GarbageCollector()
diff --git a/zmq/utils/getpid_compat.h b/zmq/utils/getpid_compat.h
new file mode 100644
index 0000000..47ce90f
--- /dev/null
+++ b/zmq/utils/getpid_compat.h
@@ -0,0 +1,6 @@
+#ifdef _WIN32
+    #include <process.h>
+    #define getpid _getpid
+#else
+    #include <unistd.h>
+#endif
diff --git a/zmq/utils/interop.py b/zmq/utils/interop.py
new file mode 100644
index 0000000..26c0196
--- /dev/null
+++ b/zmq/utils/interop.py
@@ -0,0 +1,33 @@
+"""Utils for interoperability with other libraries.
+
+Just CFFI pointer casting for now.
+"""
+
+# Copyright (C) PyZMQ Developers
+# Distributed under the terms of the Modified BSD License.
+
+
+try:
+    long
+except NameError:
+    long = int # Python 3
+
+
+def cast_int_addr(n):
+    """Cast an address to a Python int
+    
+    This could be a Python integer or a CFFI pointer
+    """
+    if isinstance(n, (int, long)):
+        return n
+    try:
+        import cffi
+    except ImportError:
+        pass
+    else:
+        # from pyzmq, this is an FFI void *
+        ffi = cffi.FFI()
+        if isinstance(n, ffi.CData):
+            return int(ffi.cast("size_t", n))
+    
+    raise ValueError("Cannot cast %r to int" % n)
diff --git a/zmq/utils/ipcmaxlen.h b/zmq/utils/ipcmaxlen.h
new file mode 100644
index 0000000..7218db7
--- /dev/null
+++ b/zmq/utils/ipcmaxlen.h
@@ -0,0 +1,21 @@
+/*
+
+Platform-independant detection of IPC path max length
+
+Copyright (c) 2012 Godefroid Chapelle
+
+Distributed under the terms of the New BSD License.  The full license is in
+the file COPYING.BSD, distributed as part of this software.
+ */
+
+#if defined(HAVE_SYS_UN_H)
+#include "sys/un.h"
+int get_ipc_path_max_len(void) {
+    struct sockaddr_un *dummy;
+    return sizeof(dummy->sun_path) - 1;
+}
+#else
+int get_ipc_path_max_len(void) {
+    return 0;
+}
+#endif
diff --git a/zmq/utils/jsonapi.py b/zmq/utils/jsonapi.py
new file mode 100644
index 0000000..865ca6d
--- /dev/null
+++ b/zmq/utils/jsonapi.py
@@ -0,0 +1,59 @@
+"""Priority based json library imports.
+
+Always serializes to bytes instead of unicode for zeromq compatibility
+on Python 2 and 3.
+
+Use ``jsonapi.loads()`` and ``jsonapi.dumps()`` for guaranteed symmetry.
+
+Priority: ``simplejson`` > ``jsonlib2`` > stdlib ``json``
+
+``jsonapi.loads/dumps`` provide kwarg-compatibility with stdlib json.
+
+``jsonapi.jsonmod`` will be the module of the actual underlying implementation.
+"""
+
+# Copyright (C) PyZMQ Developers
+# Distributed under the terms of the Modified BSD License.
+
+from zmq.utils.strtypes import bytes, unicode
+
+jsonmod = None
+
+priority = ['simplejson', 'jsonlib2', 'json']
+for mod in priority:
+    try:
+        jsonmod = __import__(mod)
+    except ImportError:
+        pass
+    else:
+        break
+
+def dumps(o, **kwargs):
+    """Serialize object to JSON bytes (utf-8).
+    
+    See jsonapi.jsonmod.dumps for details on kwargs.
+    """
+    
+    if 'separators' not in kwargs:
+        kwargs['separators'] = (',', ':')
+    
+    s = jsonmod.dumps(o, **kwargs)
+    
+    if isinstance(s, unicode):
+        s = s.encode('utf8')
+    
+    return s
+
+def loads(s, **kwargs):
+    """Load object from JSON bytes (utf-8).
+    
+    See jsonapi.jsonmod.loads for details on kwargs.
+    """
+    
+    if str is unicode and isinstance(s, bytes):
+        s = s.decode('utf8')
+    
+    return jsonmod.loads(s, **kwargs)
+
+__all__ = ['jsonmod', 'dumps', 'loads']
+
diff --git a/zmq/utils/monitor.py b/zmq/utils/monitor.py
new file mode 100644
index 0000000..734d54b
--- /dev/null
+++ b/zmq/utils/monitor.py
@@ -0,0 +1,68 @@
+# -*- coding: utf-8 -*-
+"""Module holding utility and convenience functions for zmq event monitoring."""
+
+# Copyright (C) PyZMQ Developers
+# Distributed under the terms of the Modified BSD License.
+
+import struct
+import zmq
+from zmq.error import _check_version
+
+def parse_monitor_message(msg):
+    """decode zmq_monitor event messages.
+    
+    Parameters
+    ----------
+    msg : list(bytes)
+        zmq multipart message that has arrived on a monitor PAIR socket.
+        
+        First frame is::
+        
+            16 bit event id
+            32 bit event value
+            no padding
+
+        Second frame is the endpoint as a bytestring
+
+    Returns
+    -------
+    event : dict
+        event description as dict with the keys `event`, `value`, and `endpoint`.
+    """
+    
+    if len(msg) != 2 or len(msg[0]) != 6:
+        raise RuntimeError("Invalid event message format: %s" % msg)
+    event = {}
+    event['event'], event['value'] = struct.unpack("=hi", msg[0])
+    event['endpoint'] = msg[1]
+    return event
+
+def recv_monitor_message(socket, flags=0):
+    """Receive and decode the given raw message from the monitoring socket and return a dict.
+
+    Requires libzmq ≥ 4.0
+
+    The returned dict will have the following entries:
+      event     : int, the event id as described in libzmq.zmq_socket_monitor
+      value     : int, the event value associated with the event, see libzmq.zmq_socket_monitor
+      endpoint  : string, the affected endpoint
+    
+    Parameters
+    ----------
+    socket : zmq PAIR socket
+        The PAIR socket (created by other.get_monitor_socket()) on which to recv the message
+    flags : bitfield (int)
+        standard zmq recv flags
+
+    Returns
+    -------
+    event : dict
+        event description as dict with the keys `event`, `value`, and `endpoint`.
+    """
+    _check_version((4,0), 'libzmq event API')
+    # will always return a list
+    msg = socket.recv_multipart(flags)
+    # 4.0-style event API
+    return parse_monitor_message(msg)
+
+__all__ = ['parse_monitor_message', 'recv_monitor_message']
diff --git a/zmq/utils/pyversion_compat.h b/zmq/utils/pyversion_compat.h
new file mode 100644
index 0000000..fac0904
--- /dev/null
+++ b/zmq/utils/pyversion_compat.h
@@ -0,0 +1,25 @@
+#include "Python.h"
+
+#if PY_VERSION_HEX < 0x02070000
+    #define PyMemoryView_FromBuffer(info) (PyErr_SetString(PyExc_NotImplementedError, \
+                    "new buffer interface is not available"), (PyObject *)NULL)
+    #define PyMemoryView_FromObject(object)     (PyErr_SetString(PyExc_NotImplementedError, \
+                                        "new buffer interface is not available"), (PyObject *)NULL)
+#endif
+
+#if PY_VERSION_HEX >= 0x03000000
+    // for buffers
+    #define Py_END_OF_BUFFER ((Py_ssize_t) 0)
+
+    #define PyObject_CheckReadBuffer(object) (0)
+
+    #define PyBuffer_FromMemory(ptr, s) (PyErr_SetString(PyExc_NotImplementedError, \
+                            "old buffer interface is not available"), (PyObject *)NULL)
+    #define PyBuffer_FromReadWriteMemory(ptr, s) (PyErr_SetString(PyExc_NotImplementedError, \
+                            "old buffer interface is not available"), (PyObject *)NULL)
+    #define PyBuffer_FromObject(object, offset, size)  (PyErr_SetString(PyExc_NotImplementedError, \
+                            "old buffer interface is not available"), (PyObject *)NULL)
+    #define PyBuffer_FromReadWriteObject(object, offset, size)  (PyErr_SetString(PyExc_NotImplementedError, \
+                            "old buffer interface is not available"), (PyObject *)NULL)
+
+#endif
diff --git a/zmq/utils/sixcerpt.py b/zmq/utils/sixcerpt.py
new file mode 100644
index 0000000..5492fd5
--- /dev/null
+++ b/zmq/utils/sixcerpt.py
@@ -0,0 +1,52 @@
+"""Excerpts of six.py"""
+
+# Copyright (C) 2010-2014 Benjamin Peterson
+#
+# Permission is hereby granted, free of charge, to any person obtaining a copy
+# of this software and associated documentation files (the "Software"), to deal
+# in the Software without restriction, including without limitation the rights
+# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+# copies of the Software, and to permit persons to whom the Software is
+# furnished to do so, subject to the following conditions:
+#
+# The above copyright notice and this permission notice shall be included in all
+# copies or substantial portions of the Software.
+#
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+# SOFTWARE.
+
+import sys
+
+# Useful for very coarse version differentiation.
+PY2 = sys.version_info[0] == 2
+PY3 = sys.version_info[0] == 3
+
+if PY3:
+
+    def reraise(tp, value, tb=None):
+        if value.__traceback__ is not tb:
+            raise value.with_traceback(tb)
+        raise value
+
+else:
+    def exec_(_code_, _globs_=None, _locs_=None):
+        """Execute code in a namespace."""
+        if _globs_ is None:
+            frame = sys._getframe(1)
+            _globs_ = frame.f_globals
+            if _locs_ is None:
+                _locs_ = frame.f_locals
+            del frame
+        elif _locs_ is None:
+            _locs_ = _globs_
+        exec("""exec _code_ in _globs_, _locs_""")
+
+
+    exec_("""def reraise(tp, value, tb=None):
+    raise tp, value, tb
+""")
diff --git a/zmq/utils/strtypes.py b/zmq/utils/strtypes.py
new file mode 100644
index 0000000..548410d
--- /dev/null
+++ b/zmq/utils/strtypes.py
@@ -0,0 +1,45 @@
+"""Declare basic string types unambiguously for various Python versions.
+
+Authors
+-------
+* MinRK
+"""
+
+# Copyright (C) PyZMQ Developers
+# Distributed under the terms of the Modified BSD License.
+
+import sys
+
+if sys.version_info[0] >= 3:
+    bytes = bytes
+    unicode = str
+    basestring = (bytes, unicode)
+else:
+    unicode = unicode
+    bytes = str
+    basestring = basestring
+
+def cast_bytes(s, encoding='utf8', errors='strict'):
+    """cast unicode or bytes to bytes"""
+    if isinstance(s, bytes):
+        return s
+    elif isinstance(s, unicode):
+        return s.encode(encoding, errors)
+    else:
+        raise TypeError("Expected unicode or bytes, got %r" % s)
+
+def cast_unicode(s, encoding='utf8', errors='strict'):
+    """cast bytes or unicode to unicode"""
+    if isinstance(s, bytes):
+        return s.decode(encoding, errors)
+    elif isinstance(s, unicode):
+        return s
+    else:
+        raise TypeError("Expected unicode or bytes, got %r" % s)
+
+# give short 'b' alias for cast_bytes, so that we can use fake b('stuff')
+# to simulate b'stuff'
+b = asbytes = cast_bytes
+u = cast_unicode
+
+__all__ = ['asbytes', 'bytes', 'unicode', 'basestring', 'b', 'u', 'cast_bytes', 'cast_unicode']
diff --git a/zmq/utils/win32.py b/zmq/utils/win32.py
new file mode 100644
index 0000000..e423536
--- /dev/null
+++ b/zmq/utils/win32.py
@@ -0,0 +1,132 @@
+"""Win32 compatibility utilities."""
+
+#-----------------------------------------------------------------------------
+# Copyright (C) PyZMQ Developers
+# Distributed under the terms of the Modified BSD License.
+#-----------------------------------------------------------------------------
+
+import os
+
+# No-op implementation for other platforms.
+class _allow_interrupt(object):
+    """Utility for fixing CTRL-C events on Windows.
+
+    On Windows, the Python interpreter intercepts CTRL-C events in order to
+    translate them into ``KeyboardInterrupt`` exceptions.  It (presumably)
+    does this by setting a flag in its "control control handler" and
+    checking it later at a convenient location in the interpreter.
+
+    However, when the Python interpreter is blocked waiting for the ZMQ
+    poll operation to complete, it must wait for ZMQ's ``select()``
+    operation to complete before translating the CTRL-C event into the
+    ``KeyboardInterrupt`` exception.
+
+    The only way to fix this seems to be to add our own "console control
+    handler" and perform some application-defined operation that will
+    unblock the ZMQ polling operation in order to force ZMQ to pass control
+    back to the Python interpreter.
+
+    This context manager performs all that Windows-y stuff, providing you
+    with a hook that is called when a CTRL-C event is intercepted.  This
+    hook allows you to unblock your ZMQ poll operation immediately, which
+    will then result in the expected ``KeyboardInterrupt`` exception.
+
+    Without this context manager, your ZMQ-based application will not
+    respond normally to CTRL-C events on Windows.  If a CTRL-C event occurs
+    while blocked on ZMQ socket polling, the translation to a
+    ``KeyboardInterrupt`` exception will be delayed until the I/O completes
+    and control returns to the Python interpreter (this may never happen if
+    you use an infinite timeout).
+
+    A no-op implementation is provided on non-Win32 systems to avoid the
+    application from having to conditionally use it.
+
+    Example usage:
+
+    .. sourcecode:: python
+
+       def stop_my_application():
+           # ...
+
+       with allow_interrupt(stop_my_application):
+           # main polling loop.
+
+    In a typical ZMQ application, you would use the "self pipe trick" to
+    send message to a ``PAIR`` socket in order to interrupt your blocking
+    socket polling operation.
+
+    In a Tornado event loop, you can use the ``IOLoop.stop`` method to
+    unblock your I/O loop.
+    """
+
+    def __init__(self, action=None):
+        """Translate ``action`` into a CTRL-C handler.
+
+        ``action`` is a callable that takes no arguments and returns no
+        value (returned value is ignored).  It must *NEVER* raise an
+        exception.
+        
+        If unspecified, a no-op will be used.
+        """
+        self._init_action(action)
+    
+    def _init_action(self, action):
+        pass
+
+    def __enter__(self):
+        return self
+
+    def __exit__(self, *args):
+        return
+
+if os.name == 'nt':
+    from ctypes import WINFUNCTYPE, windll
+    from ctypes.wintypes import BOOL, DWORD
+
+    kernel32 = windll.LoadLibrary('kernel32')
+
+    # <http://msdn.microsoft.com/en-us/library/ms686016.aspx>
+    PHANDLER_ROUTINE = WINFUNCTYPE(BOOL, DWORD)
+    SetConsoleCtrlHandler = kernel32.SetConsoleCtrlHandler
+    SetConsoleCtrlHandler.argtypes = (PHANDLER_ROUTINE, BOOL)
+    SetConsoleCtrlHandler.restype = BOOL
+
+    class allow_interrupt(_allow_interrupt):
+        __doc__ = _allow_interrupt.__doc__
+
+        def init_action(self, action):
+            if action is None:
+                action = lambda: None
+            self.action = action
+            @PHANDLER_ROUTINE
+            def handle(event):
+                if event == 0:  # CTRL_C_EVENT
+                    action()
+                    # Typical C implementations would return 1 to indicate that
+                    # the event was processed and other control handlers in the
+                    # stack should not be executed.  However, that would
+                    # prevent the Python interpreter's handler from translating
+                    # CTRL-C to a `KeyboardInterrupt` exception, so we pretend
+                    # that we didn't handle it.
+                return 0
+            self.handle = handle
+
+        def __enter__(self):
+            """Install the custom CTRL-C handler."""
+            result = SetConsoleCtrlHandler(self.handle, 1)
+            if result == 0:
+                # Have standard library automatically call `GetLastError()` and
+                # `FormatMessage()` into a nice exception object :-)
+                raise WindowsError()
+
+        def __exit__(self, *args):
+            """Remove the custom CTRL-C handler."""
+            result = SetConsoleCtrlHandler(self.handle, 0)
+            if result == 0:
+                # Have standard library automatically call `GetLastError()` and
+                # `FormatMessage()` into a nice exception object :-)
+                raise WindowsError()
+else:
+    class allow_interrupt(_allow_interrupt):
+        __doc__ = _allow_interrupt.__doc__
+        pass
diff --git a/zmq/utils/z85.py b/zmq/utils/z85.py
new file mode 100644
index 0000000..1bb1784
--- /dev/null
+++ b/zmq/utils/z85.py
@@ -0,0 +1,56 @@
+"""Python implementation of Z85 85-bit encoding
+
+Z85 encoding is a plaintext encoding for a bytestring interpreted as 32bit integers.
+Since the chunks are 32bit, a bytestring must be a multiple of 4 bytes.
+See ZMQ RFC 32 for details.
+
+
+"""
+
+# Copyright (C) PyZMQ Developers
+# Distributed under the terms of the Modified BSD License.
+
+import sys
+import struct
+
+PY3 = sys.version_info[0] >= 3
+# Z85CHARS is the base 85 symbol table
+Z85CHARS = b"0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ.-:+=^!/*?&<>()[]{}@%$#"
+# Z85MAP maps integers in [0,84] to the appropriate character in Z85CHARS
+Z85MAP = dict([(c, idx) for idx, c in enumerate(Z85CHARS)])
+
+_85s = [ 85**i for i in range(5) ][::-1]
+
+def encode(rawbytes):
+    """encode raw bytes into Z85"""
+    # Accepts only byte arrays bounded to 4 bytes
+    if len(rawbytes) % 4:
+        raise ValueError("length must be multiple of 4, not %i" % len(rawbytes))
+    
+    nvalues = len(rawbytes) / 4
+    
+    values = struct.unpack('>%dI' % nvalues, rawbytes)
+    encoded = []
+    for v in values:
+        for offset in _85s:
+            encoded.append(Z85CHARS[(v // offset) % 85])
+    
+    # In Python 3, encoded is a list of integers (obviously?!)
+    if PY3:
+        return bytes(encoded)
+    else:
+        return b''.join(encoded)
+
+def decode(z85bytes):
+    """decode Z85 bytes to raw bytes"""
+    if len(z85bytes) % 5:
+        raise ValueError("Z85 length must be multiple of 5, not %i" % len(z85bytes))
+    
+    nvalues = len(z85bytes) / 5
+    values = []
+    for i in range(0, len(z85bytes), 5):
+        value = 0
+        for j, offset in enumerate(_85s):
+            value += Z85MAP[z85bytes[i+j]] * offset
+        values.append(value)
+    return struct.pack('>%dI' % nvalues, *values)
diff --git a/zmq/utils/zmq_compat.h b/zmq/utils/zmq_compat.h
new file mode 100644
index 0000000..81c57b6
--- /dev/null
+++ b/zmq/utils/zmq_compat.h
@@ -0,0 +1,80 @@
+//-----------------------------------------------------------------------------
+//  Copyright (c) 2010 Brian Granger, Min Ragan-Kelley
+//
+//  Distributed under the terms of the New BSD License.  The full license is in
+//  the file COPYING.BSD, distributed as part of this software.
+//-----------------------------------------------------------------------------
+
+#if defined(_MSC_VER)
+#define pyzmq_int64_t __int64
+#else
+#include <stdint.h>
+#define pyzmq_int64_t int64_t
+#endif
+
+
+#include "zmq.h"
+// version compatibility for constants:
+#include "zmq_constants.h"
+
+#define _missing (-1)
+
+
+// define fd type (from libzmq's fd.hpp)
+#ifdef _WIN32
+  #ifdef _MSC_VER && _MSC_VER <= 1400
+    #define ZMQ_FD_T UINT_PTR
+  #else
+    #define ZMQ_FD_T SOCKET
+  #endif
+#else
+    #define ZMQ_FD_T int
+#endif
+
+// use unambiguous aliases for zmq_send/recv functions
+
+#if ZMQ_VERSION_MAJOR >= 4
+// nothing to remove
+#else
+    #define zmq_curve_keypair(z85_public_key, z85_secret_key) _missing
+#endif
+
+#if ZMQ_VERSION_MAJOR >= 4 && ZMQ_VERSION_MINOR >= 1
+// nothing to remove
+#else
+    #define zmq_msg_gets(msg, prop) _missing
+    #define zmq_has(capability) _missing
+#endif
+
+#if ZMQ_VERSION_MAJOR >= 3
+    #define zmq_sendbuf zmq_send
+    #define zmq_recvbuf zmq_recv
+
+    // 3.x deprecations - these symbols haven't been removed,
+    // but let's protect against their planned removal
+    #define zmq_device(device_type, isocket, osocket) _missing
+    #define zmq_init(io_threads) ((void*)NULL)
+    #define zmq_term zmq_ctx_destroy
+#else
+    #define zmq_ctx_set(ctx, opt, val) _missing
+    #define zmq_ctx_get(ctx, opt) _missing
+    #define zmq_ctx_destroy zmq_term
+    #define zmq_ctx_new() ((void*)NULL)
+
+    #define zmq_proxy(a,b,c) _missing
+
+    #define zmq_disconnect(s, addr) _missing
+    #define zmq_unbind(s, addr) _missing
+    
+    #define zmq_msg_more(msg) _missing
+    #define zmq_msg_get(msg, opt) _missing
+    #define zmq_msg_set(msg, opt, val) _missing
+    #define zmq_msg_send(msg, s, flags) zmq_send(s, msg, flags)
+    #define zmq_msg_recv(msg, s, flags) zmq_recv(s, msg, flags)
+    
+    #define zmq_sendbuf(s, buf, len, flags) _missing
+    #define zmq_recvbuf(s, buf, len, flags) _missing
+
+    #define zmq_socket_monitor(s, addr, flags) _missing
+
+#endif
diff --git a/zmq/utils/zmq_constants.h b/zmq/utils/zmq_constants.h
new file mode 100644
index 0000000..9768302
--- /dev/null
+++ b/zmq/utils/zmq_constants.h
@@ -0,0 +1,622 @@
+#ifndef _PYZMQ_CONSTANT_DEFS
+#define _PYZMQ_CONSTANT_DEFS
+
+#define _PYZMQ_UNDEFINED (-9999)
+#ifndef ZMQ_VERSION
+    #define ZMQ_VERSION (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_VERSION_MAJOR
+    #define ZMQ_VERSION_MAJOR (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_VERSION_MINOR
+    #define ZMQ_VERSION_MINOR (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_VERSION_PATCH
+    #define ZMQ_VERSION_PATCH (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_NOBLOCK
+    #define ZMQ_NOBLOCK (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_DONTWAIT
+    #define ZMQ_DONTWAIT (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_POLLIN
+    #define ZMQ_POLLIN (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_POLLOUT
+    #define ZMQ_POLLOUT (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_POLLERR
+    #define ZMQ_POLLERR (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_SNDMORE
+    #define ZMQ_SNDMORE (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_STREAMER
+    #define ZMQ_STREAMER (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_FORWARDER
+    #define ZMQ_FORWARDER (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_QUEUE
+    #define ZMQ_QUEUE (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_IO_THREADS_DFLT
+    #define ZMQ_IO_THREADS_DFLT (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_MAX_SOCKETS_DFLT
+    #define ZMQ_MAX_SOCKETS_DFLT (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_POLLITEMS_DFLT
+    #define ZMQ_POLLITEMS_DFLT (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_THREAD_PRIORITY_DFLT
+    #define ZMQ_THREAD_PRIORITY_DFLT (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_THREAD_SCHED_POLICY_DFLT
+    #define ZMQ_THREAD_SCHED_POLICY_DFLT (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_PAIR
+    #define ZMQ_PAIR (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_PUB
+    #define ZMQ_PUB (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_SUB
+    #define ZMQ_SUB (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_REQ
+    #define ZMQ_REQ (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_REP
+    #define ZMQ_REP (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_DEALER
+    #define ZMQ_DEALER (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_ROUTER
+    #define ZMQ_ROUTER (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_XREQ
+    #define ZMQ_XREQ (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_XREP
+    #define ZMQ_XREP (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_PULL
+    #define ZMQ_PULL (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_PUSH
+    #define ZMQ_PUSH (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_XPUB
+    #define ZMQ_XPUB (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_XSUB
+    #define ZMQ_XSUB (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_UPSTREAM
+    #define ZMQ_UPSTREAM (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_DOWNSTREAM
+    #define ZMQ_DOWNSTREAM (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_STREAM
+    #define ZMQ_STREAM (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_EVENT_CONNECTED
+    #define ZMQ_EVENT_CONNECTED (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_EVENT_CONNECT_DELAYED
+    #define ZMQ_EVENT_CONNECT_DELAYED (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_EVENT_CONNECT_RETRIED
+    #define ZMQ_EVENT_CONNECT_RETRIED (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_EVENT_LISTENING
+    #define ZMQ_EVENT_LISTENING (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_EVENT_BIND_FAILED
+    #define ZMQ_EVENT_BIND_FAILED (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_EVENT_ACCEPTED
+    #define ZMQ_EVENT_ACCEPTED (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_EVENT_ACCEPT_FAILED
+    #define ZMQ_EVENT_ACCEPT_FAILED (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_EVENT_CLOSED
+    #define ZMQ_EVENT_CLOSED (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_EVENT_CLOSE_FAILED
+    #define ZMQ_EVENT_CLOSE_FAILED (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_EVENT_DISCONNECTED
+    #define ZMQ_EVENT_DISCONNECTED (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_EVENT_ALL
+    #define ZMQ_EVENT_ALL (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_EVENT_MONITOR_STOPPED
+    #define ZMQ_EVENT_MONITOR_STOPPED (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_NULL
+    #define ZMQ_NULL (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_PLAIN
+    #define ZMQ_PLAIN (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_CURVE
+    #define ZMQ_CURVE (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_GSSAPI
+    #define ZMQ_GSSAPI (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef EAGAIN
+    #define EAGAIN (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef EINVAL
+    #define EINVAL (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef EFAULT
+    #define EFAULT (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ENOMEM
+    #define ENOMEM (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ENODEV
+    #define ENODEV (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef EMSGSIZE
+    #define EMSGSIZE (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef EAFNOSUPPORT
+    #define EAFNOSUPPORT (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ENETUNREACH
+    #define ENETUNREACH (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ECONNABORTED
+    #define ECONNABORTED (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ECONNRESET
+    #define ECONNRESET (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ENOTCONN
+    #define ENOTCONN (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ETIMEDOUT
+    #define ETIMEDOUT (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef EHOSTUNREACH
+    #define EHOSTUNREACH (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ENETRESET
+    #define ENETRESET (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_HAUSNUMERO
+    #define ZMQ_HAUSNUMERO (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ENOTSUP
+    #define ENOTSUP (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef EPROTONOSUPPORT
+    #define EPROTONOSUPPORT (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ENOBUFS
+    #define ENOBUFS (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ENETDOWN
+    #define ENETDOWN (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef EADDRINUSE
+    #define EADDRINUSE (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef EADDRNOTAVAIL
+    #define EADDRNOTAVAIL (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ECONNREFUSED
+    #define ECONNREFUSED (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef EINPROGRESS
+    #define EINPROGRESS (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ENOTSOCK
+    #define ENOTSOCK (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef EFSM
+    #define EFSM (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ENOCOMPATPROTO
+    #define ENOCOMPATPROTO (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ETERM
+    #define ETERM (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef EMTHREAD
+    #define EMTHREAD (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_IO_THREADS
+    #define ZMQ_IO_THREADS (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_MAX_SOCKETS
+    #define ZMQ_MAX_SOCKETS (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_SOCKET_LIMIT
+    #define ZMQ_SOCKET_LIMIT (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_THREAD_PRIORITY
+    #define ZMQ_THREAD_PRIORITY (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_THREAD_SCHED_POLICY
+    #define ZMQ_THREAD_SCHED_POLICY (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_IDENTITY
+    #define ZMQ_IDENTITY (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_SUBSCRIBE
+    #define ZMQ_SUBSCRIBE (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_UNSUBSCRIBE
+    #define ZMQ_UNSUBSCRIBE (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_LAST_ENDPOINT
+    #define ZMQ_LAST_ENDPOINT (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_TCP_ACCEPT_FILTER
+    #define ZMQ_TCP_ACCEPT_FILTER (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_PLAIN_USERNAME
+    #define ZMQ_PLAIN_USERNAME (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_PLAIN_PASSWORD
+    #define ZMQ_PLAIN_PASSWORD (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_CURVE_PUBLICKEY
+    #define ZMQ_CURVE_PUBLICKEY (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_CURVE_SECRETKEY
+    #define ZMQ_CURVE_SECRETKEY (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_CURVE_SERVERKEY
+    #define ZMQ_CURVE_SERVERKEY (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_ZAP_DOMAIN
+    #define ZMQ_ZAP_DOMAIN (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_CONNECT_RID
+    #define ZMQ_CONNECT_RID (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_GSSAPI_PRINCIPAL
+    #define ZMQ_GSSAPI_PRINCIPAL (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_GSSAPI_SERVICE_PRINCIPAL
+    #define ZMQ_GSSAPI_SERVICE_PRINCIPAL (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_SOCKS_PROXY
+    #define ZMQ_SOCKS_PROXY (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_FD
+    #define ZMQ_FD (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_IDENTITY_FD
+    #define ZMQ_IDENTITY_FD (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_RECONNECT_IVL_MAX
+    #define ZMQ_RECONNECT_IVL_MAX (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_SNDTIMEO
+    #define ZMQ_SNDTIMEO (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_RCVTIMEO
+    #define ZMQ_RCVTIMEO (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_SNDHWM
+    #define ZMQ_SNDHWM (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_RCVHWM
+    #define ZMQ_RCVHWM (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_MULTICAST_HOPS
+    #define ZMQ_MULTICAST_HOPS (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_IPV4ONLY
+    #define ZMQ_IPV4ONLY (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_ROUTER_BEHAVIOR
+    #define ZMQ_ROUTER_BEHAVIOR (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_TCP_KEEPALIVE
+    #define ZMQ_TCP_KEEPALIVE (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_TCP_KEEPALIVE_CNT
+    #define ZMQ_TCP_KEEPALIVE_CNT (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_TCP_KEEPALIVE_IDLE
+    #define ZMQ_TCP_KEEPALIVE_IDLE (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_TCP_KEEPALIVE_INTVL
+    #define ZMQ_TCP_KEEPALIVE_INTVL (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_DELAY_ATTACH_ON_CONNECT
+    #define ZMQ_DELAY_ATTACH_ON_CONNECT (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_XPUB_VERBOSE
+    #define ZMQ_XPUB_VERBOSE (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_EVENTS
+    #define ZMQ_EVENTS (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_TYPE
+    #define ZMQ_TYPE (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_LINGER
+    #define ZMQ_LINGER (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_RECONNECT_IVL
+    #define ZMQ_RECONNECT_IVL (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_BACKLOG
+    #define ZMQ_BACKLOG (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_ROUTER_MANDATORY
+    #define ZMQ_ROUTER_MANDATORY (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_FAIL_UNROUTABLE
+    #define ZMQ_FAIL_UNROUTABLE (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_ROUTER_RAW
+    #define ZMQ_ROUTER_RAW (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_IMMEDIATE
+    #define ZMQ_IMMEDIATE (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_IPV6
+    #define ZMQ_IPV6 (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_MECHANISM
+    #define ZMQ_MECHANISM (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_PLAIN_SERVER
+    #define ZMQ_PLAIN_SERVER (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_CURVE_SERVER
+    #define ZMQ_CURVE_SERVER (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_PROBE_ROUTER
+    #define ZMQ_PROBE_ROUTER (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_REQ_RELAXED
+    #define ZMQ_REQ_RELAXED (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_REQ_CORRELATE
+    #define ZMQ_REQ_CORRELATE (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_CONFLATE
+    #define ZMQ_CONFLATE (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_ROUTER_HANDOVER
+    #define ZMQ_ROUTER_HANDOVER (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_TOS
+    #define ZMQ_TOS (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_IPC_FILTER_PID
+    #define ZMQ_IPC_FILTER_PID (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_IPC_FILTER_UID
+    #define ZMQ_IPC_FILTER_UID (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_IPC_FILTER_GID
+    #define ZMQ_IPC_FILTER_GID (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_GSSAPI_SERVER
+    #define ZMQ_GSSAPI_SERVER (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_GSSAPI_PLAINTEXT
+    #define ZMQ_GSSAPI_PLAINTEXT (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_HANDSHAKE_IVL
+    #define ZMQ_HANDSHAKE_IVL (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_XPUB_NODROP
+    #define ZMQ_XPUB_NODROP (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_AFFINITY
+    #define ZMQ_AFFINITY (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_MAXMSGSIZE
+    #define ZMQ_MAXMSGSIZE (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_HWM
+    #define ZMQ_HWM (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_SWAP
+    #define ZMQ_SWAP (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_MCAST_LOOP
+    #define ZMQ_MCAST_LOOP (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_RECOVERY_IVL_MSEC
+    #define ZMQ_RECOVERY_IVL_MSEC (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_RATE
+    #define ZMQ_RATE (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_RECOVERY_IVL
+    #define ZMQ_RECOVERY_IVL (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_SNDBUF
+    #define ZMQ_SNDBUF (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_RCVBUF
+    #define ZMQ_RCVBUF (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_RCVMORE
+    #define ZMQ_RCVMORE (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_MORE
+    #define ZMQ_MORE (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_SRCFD
+    #define ZMQ_SRCFD (_PYZMQ_UNDEFINED)
+#endif
+
+#ifndef ZMQ_SHARED
+    #define ZMQ_SHARED (_PYZMQ_UNDEFINED)
+#endif
+
+
+#endif // ifndef _PYZMQ_CONSTANT_DEFS