initial commit1.07-1

2 files changed, 1631 insertions, 0 deletions

diff --git a/debian/python-sh/usr/share/pyshared/sh-1.07.egg-info b/debian/python-sh/usr/share/pyshared/sh-1.07.egg-info
new file mode 100644
index 0000000..1178d80
--- /dev/null
+++ b/debian/python-sh/usr/share/pyshared/sh-1.07.egg-info
@@ -0,0 +1,25 @@
+Metadata-Version: 1.1
+Name: sh
+Version: 1.07
+Summary: Python subprocess interface
+Home-page: https://github.com/amoffat/sh
+Author: Andrew Moffat
+Author-email: andrew.robert.moffat@gmail.com
+License: MIT
+Description: UNKNOWN
+Platform: UNKNOWN
+Classifier: Development Status :: 4 - Beta
+Classifier: Environment :: Console
+Classifier: Intended Audience :: Developers
+Classifier: Intended Audience :: System Administrators
+Classifier: License :: OSI Approved :: MIT License
+Classifier: Programming Language :: Python
+Classifier: Programming Language :: Python :: 2
+Classifier: Programming Language :: Python :: 2.6
+Classifier: Programming Language :: Python :: 2.7
+Classifier: Programming Language :: Python :: 3
+Classifier: Programming Language :: Python :: 3.1
+Classifier: Programming Language :: Python :: 3.2
+Classifier: Programming Language :: Python :: 3.3
+Classifier: Topic :: Software Development :: Build Tools
+Classifier: Topic :: Software Development :: Libraries :: Python Modules
diff --git a/debian/python-sh/usr/share/pyshared/sh.py b/debian/python-sh/usr/share/pyshared/sh.py
new file mode 100644
index 0000000..54bf92d
--- /dev/null
+++ b/debian/python-sh/usr/share/pyshared/sh.py
@@ -0,0 +1,1606 @@
+#===============================================================================
+# Copyright (C) 2011-2012 by Andrew Moffat
+# 
+# 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.
+#===============================================================================
+
+
+__version__ = "1.07"
+__project_url__ = "https://github.com/amoffat/sh"
+
+
+
+import platform
+
+if "windows" in platform.system().lower():
+    raise ImportError("sh %s is currently only supported on linux and osx. \
+please install pbs 0.110 (http://pypi.python.org/pypi/pbs) for windows \
+support." % __version__)
+
+
+
+import sys
+IS_PY3 = sys.version_info[0] == 3
+
+import traceback
+import os
+import re
+from glob import glob as original_glob
+from types import ModuleType
+from functools import partial
+import inspect
+import time as _time
+
+from locale import getpreferredencoding
+DEFAULT_ENCODING = getpreferredencoding() or "utf-8"
+
+
+if IS_PY3:
+    from io import StringIO
+    from io import BytesIO as cStringIO
+    from queue import Queue, Empty
+else:
+    from StringIO import StringIO
+    from cStringIO import OutputType as cStringIO
+    from Queue import Queue, Empty
+    
+IS_OSX = platform.system() == "Darwin"
+THIS_DIR = os.path.dirname(os.path.realpath(__file__))
+
+
+import errno
+import warnings
+
+import pty
+import termios
+import signal
+import gc
+import select
+import atexit
+import threading
+import tty
+import fcntl
+import struct
+import resource
+from collections import deque
+import logging
+import weakref
+
+
+logging_enabled = False
+
+
+if IS_PY3:
+    raw_input = input
+    unicode = str
+    basestring = str
+
+
+
+
+class ErrorReturnCode(Exception):
+    truncate_cap = 750
+
+    def __init__(self, full_cmd, stdout, stderr):
+        self.full_cmd = full_cmd
+        self.stdout = stdout
+        self.stderr = stderr
+
+
+        if self.stdout is None: tstdout = "<redirected>"
+        else:
+            tstdout = self.stdout[:self.truncate_cap] 
+            out_delta = len(self.stdout) - len(tstdout)
+            if out_delta: 
+                tstdout += ("... (%d more, please see e.stdout)" % out_delta).encode()
+            
+        if self.stderr is None: tstderr = "<redirected>"
+        else:
+            tstderr = self.stderr[:self.truncate_cap]
+            err_delta = len(self.stderr) - len(tstderr)
+            if err_delta: 
+                tstderr += ("... (%d more, please see e.stderr)" % err_delta).encode()
+
+        msg = "\n\n  RAN: %r\n\n  STDOUT:\n%s\n\n  STDERR:\n%s" %\
+            (full_cmd, tstdout.decode(DEFAULT_ENCODING), tstderr.decode(DEFAULT_ENCODING))
+        super(ErrorReturnCode, self).__init__(msg)
+
+
+# we subclass AttributeError because:
+# https://github.com/ipython/ipython/issues/2577
+# https://github.com/amoffat/sh/issues/97#issuecomment-10610629
+class CommandNotFound(AttributeError): pass
+
+rc_exc_regex = re.compile("ErrorReturnCode_(\d+)")
+rc_exc_cache = {}
+
+def get_rc_exc(rc):
+    rc = int(rc)
+    try: return rc_exc_cache[rc]
+    except KeyError: pass
+    
+    name = "ErrorReturnCode_%d" % rc
+    exc = type(name, (ErrorReturnCode,), {})
+    rc_exc_cache[rc] = exc
+    return exc
+
+
+
+
+def which(program):
+    def is_exe(fpath):
+        return os.path.exists(fpath) and os.access(fpath, os.X_OK)
+
+    fpath, fname = os.path.split(program)
+    if fpath:
+        if is_exe(program): return program
+    else:
+        if "PATH" not in os.environ: return None
+        for path in os.environ["PATH"].split(os.pathsep):
+            exe_file = os.path.join(path, program)
+            if is_exe(exe_file):
+                return exe_file
+
+    return None
+
+def resolve_program(program):
+    path = which(program)
+    if not path:
+        # our actual command might have a dash in it, but we can't call
+        # that from python (we have to use underscores), so we'll check
+        # if a dash version of our underscore command exists and use that
+        # if it does
+        if "_" in program: path = which(program.replace("_", "-"))        
+        if not path: return None
+    return path
+
+
+# we add this thin wrapper to glob.glob because of a specific edge case where
+# glob does not expand to anything.  for example, if you try to do
+# glob.glob("*.py") and there are no *.py files in the directory, glob.glob
+# returns an empty list.  this empty list gets passed to the command, and
+# then the command fails with a misleading error message.  this thin wrapper
+# ensures that if there is no expansion, we pass in the original argument,
+# so that when the command fails, the error message is clearer
+def glob(arg):    
+    return original_glob(arg) or arg
+
+
+
+class Logger(object):
+    def __init__(self, name, context=None):
+        self.name = name
+        self.context = "%s"
+        if context: self.context = "%s: %%s" % context
+        self.log = logging.getLogger(name)
+    
+    def info(self, msg, *args):
+        if not logging_enabled: return
+        self.log.info(self.context, msg % args)
+        
+    def debug(self, msg, *args):
+        if not logging_enabled: return
+        self.log.debug(self.context, msg % args)
+        
+    def error(self, msg, *args):
+        if not logging_enabled: return
+        self.log.error(self.context, msg % args)
+        
+    def exception(self, msg, *args):
+        if not logging_enabled: return
+        self.log.exception(self.context, msg % args)
+
+
+
+class RunningCommand(object):
+    def __init__(self, cmd, call_args, stdin, stdout, stderr):
+        truncate = 20
+        if len(cmd) > truncate:
+            logger_str = "command %r...(%d more) call_args %r" % \
+                (cmd[:truncate], len(cmd) - truncate, call_args)
+        else:
+            logger_str = "command %r call_args %r" % (cmd, call_args)
+        
+        self.log = Logger("command", logger_str)
+        self.call_args = call_args
+        self.cmd = cmd
+        self.ran = " ".join(cmd)
+        self.process = None
+
+        self.should_wait = True
+        spawn_process = True
+
+
+        # with contexts shouldn't run at all yet, they prepend
+        # to every command in the context
+        if call_args["with"]:
+            spawn_process = False
+            Command._prepend_stack.append(self)
+            
+
+        if callable(call_args["out"]) or callable(call_args["err"]):
+            self.should_wait = False
+            
+        if call_args["piped"] or call_args["iter"] or call_args["iter_noblock"]:
+            self.should_wait = False
+            
+        # we're running in the background, return self and let us lazily
+        # evaluate
+        if call_args["bg"]: self.should_wait = False
+
+        # redirection
+        if call_args["err_to_out"]: stderr = STDOUT
+        
+        
+        # set up which stream should write to the pipe
+        # TODO, make pipe None by default and limit the size of the Queue
+        # in oproc.OProc
+        pipe = STDOUT
+        if call_args["iter"] == "out" or call_args["iter"] is True: pipe = STDOUT
+        elif call_args["iter"] == "err": pipe = STDERR
+        
+        if call_args["iter_noblock"] == "out" or call_args["iter_noblock"] is True: pipe = STDOUT
+        elif call_args["iter_noblock"] == "err": pipe = STDERR
+        
+        
+        if spawn_process:
+            self.log.debug("starting process")
+            self.process = OProc(cmd, stdin, stdout, stderr, 
+                self.call_args, pipe=pipe)
+            
+            if self.should_wait:
+                self.wait()
+        
+
+    def wait(self):
+        self._handle_exit_code(self.process.wait())
+        return self
+    
+    # here we determine if we had an exception, or an error code that we weren't
+    # expecting to see.  if we did, we create and raise an exception
+    def _handle_exit_code(self, code):
+        if code not in self.call_args["ok_code"] and code >= 0: raise get_rc_exc(code)(
+            " ".join(self.cmd),
+            self.process.stdout,
+            self.process.stderr
+        )        
+
+    @property
+    def stdout(self):
+        self.wait()
+        return self.process.stdout
+    
+    @property
+    def stderr(self):
+        self.wait()
+        return self.process.stderr
+    
+    @property
+    def exit_code(self):
+        self.wait()
+        return self.process.exit_code
+    
+    @property
+    def pid(self):
+        return self.process.pid
+    
+    def __len__(self):
+        return len(str(self))
+    
+    def __enter__(self):
+        # we don't actually do anything here because anything that should
+        # have been done would have been done in the Command.__call__ call.
+        # essentially all that has to happen is the comand be pushed on
+        # the prepend stack.
+        pass
+    
+    def __iter__(self):
+        return self
+    
+    def next(self):
+        # we do this because if get blocks, we can't catch a KeyboardInterrupt
+        # so the slight timeout allows for that.
+        while True:
+            try: chunk = self.process._pipe_queue.get(False, .001)
+            except Empty:
+                if self.call_args["iter_noblock"]: return errno.EWOULDBLOCK
+            else:
+                if chunk is None:
+                    self.wait()
+                    raise StopIteration()
+                try: return chunk.decode(self.call_args["encoding"],
+                    self.call_args["decode_errors"])
+                except UnicodeDecodeError: return chunk
+            
+    # python 3
+    __next__ = next
+
+    def __exit__(self, typ, value, traceback):
+        if self.call_args["with"] and Command._prepend_stack:
+            Command._prepend_stack.pop()
+   
+    def __str__(self):
+        if IS_PY3: return self.__unicode__()
+        else: return unicode(self).encode(self.call_args["encoding"])
+        
+    def __unicode__(self):
+        if self.process and self.stdout:
+            return self.stdout.decode(self.call_args["encoding"],
+                self.call_args["decode_errors"])
+        return ""
+
+    def __eq__(self, other):
+        return unicode(self) == unicode(other)
+
+    def __contains__(self, item):
+        return item in str(self)
+
+    def __getattr__(self, p):
+        # let these three attributes pass through to the OProc object
+        if p in ("signal", "terminate", "kill"):
+            if self.process: return getattr(self.process, p)
+            else: raise AttributeError
+        return getattr(unicode(self), p)
+     
+    def __repr__(self):
+        try: return str(self)
+        except UnicodeDecodeError:
+            if self.process: 
+                if self.stdout: return repr(self.stdout)
+            return repr("")
+
+    def __long__(self):
+        return long(str(self).strip())
+
+    def __float__(self):
+        return float(str(self).strip())
+
+    def __int__(self):
+        return int(str(self).strip())
+
+
+
+
+
+class Command(object):
+    _prepend_stack = []
+    
+    _call_args = {
+        # currently unsupported
+        #"fg": False, # run command in foreground
+        
+        "bg": False, # run command in background
+        "with": False, # prepend the command to every command after it
+        "in": None,
+        "out": None, # redirect STDOUT
+        "err": None, # redirect STDERR
+        "err_to_out": None, # redirect STDERR to STDOUT
+        
+        # stdin buffer size
+        # 1 for line, 0 for unbuffered, any other number for that amount
+        "in_bufsize": 0,
+        # stdout buffer size, same values as above
+        "out_bufsize": 1,
+        "err_bufsize": 1,
+        
+        # this is how big the output buffers will be for stdout and stderr.
+        # this is essentially how much output they will store from the process.
+        # we use a deque, so if it overflows past this amount, the first items
+        # get pushed off as each new item gets added.
+        # 
+        # NOTICE
+        # this is not a *BYTE* size, this is a *CHUNK* size...meaning, that if
+        # you're buffering out/err at 1024 bytes, the internal buffer size will
+        # be "internal_bufsize" CHUNKS of 1024 bytes
+        "internal_bufsize": 3 * 1024**2,
+        
+        "env": None,
+        "piped": None,
+        "iter": None,
+        "iter_noblock": None,
+        "ok_code": 0,
+        "cwd": None,
+        
+        # this is for programs that expect their input to be from a terminal.
+        # ssh is one of those programs
+        "tty_in": False,
+        "tty_out": True,
+        
+        "encoding": DEFAULT_ENCODING,
+        "decode_errors": "strict",
+        
+        # how long the process should run before it is auto-killed
+        "timeout": 0,
+        
+        # these control whether or not stdout/err will get aggregated together
+        # as the process runs.  this has memory usage implications, so sometimes
+        # with long-running processes with a lot of data, it makes sense to
+        # set these to true
+        "no_out": False,
+        "no_err": False,
+        "no_pipe": False,
+        
+        # if any redirection is used for stdout or stderr, internal buffering
+        # of that data is not stored.  this forces it to be stored, as if
+        # the output is being T'd to both the redirected destination and our
+        # internal buffers
+        "tee": None,
+    }
+    
+    # these are arguments that cannot be called together, because they wouldn't
+    # make any sense
+    _incompatible_call_args = (
+        #("fg", "bg", "Command can't be run in the foreground and background"),
+        ("err", "err_to_out", "Stderr is already being redirected"),
+        ("piped", "iter", "You cannot iterate when this command is being piped"),
+    )
+
+    @classmethod
+    def _create(cls, program):
+        path = resolve_program(program)
+        if not path: raise CommandNotFound(program)
+        return cls(path)
+    
+    def __init__(self, path):
+        self._path = which(path)
+        self._partial = False
+        self._partial_baked_args = []
+        self._partial_call_args = {}
+        
+    def __getattribute__(self, name):
+        # convenience
+        getattr = partial(object.__getattribute__, self)
+        
+        if name.startswith("_"): return getattr(name)    
+        if name == "bake": return getattr("bake")         
+        return getattr("bake")(name)
+
+    
+    @staticmethod
+    def _extract_call_args(kwargs, to_override={}):
+        kwargs = kwargs.copy()
+        call_args = {}
+        for parg, default in Command._call_args.items():
+            key = "_" + parg
+            
+            if key in kwargs:
+                call_args[parg] = kwargs[key] 
+                del kwargs[key]
+            elif parg in to_override:
+                call_args[parg] = to_override[parg]
+        
+        # test for incompatible call args
+        s1 = set(call_args.keys())
+        for args in Command._incompatible_call_args:
+            args = list(args)
+            error = args.pop()
+
+            if s1.issuperset(args):
+                raise TypeError("Invalid special arguments %r: %s" % (args, error))
+            
+        return call_args, kwargs
+
+
+    def _format_arg(self, arg):
+        if IS_PY3: arg = str(arg)
+        else: arg = unicode(arg).encode(DEFAULT_ENCODING)
+        return arg
+
+    def _compile_args(self, args, kwargs):
+        processed_args = []
+                
+        # aggregate positional args
+        for arg in args:
+            if isinstance(arg, (list, tuple)):
+                if not arg:
+                    warnings.warn("Empty list passed as an argument to %r. \
+If you're using glob.glob(), please use sh.glob() instead." % self.path, stacklevel=3)
+                for sub_arg in arg: processed_args.append(self._format_arg(sub_arg))
+            else: processed_args.append(self._format_arg(arg))
+
+        # aggregate the keyword arguments
+        for k,v in kwargs.items():
+            # we're passing a short arg as a kwarg, example:
+            # cut(d="\t")
+            if len(k) == 1:
+                if v is not False:
+                    processed_args.append("-"+k)
+                    if v is not True: processed_args.append(self._format_arg(v))
+
+            # we're doing a long arg
+            else:
+                k = k.replace("_", "-")
+
+                if v is True: processed_args.append("--"+k)
+                elif v is False: pass
+                else: processed_args.append("--%s=%s" % (k, self._format_arg(v)))
+
+        return processed_args
+ 
+    
+    def bake(self, *args, **kwargs):
+        fn = Command(self._path)
+        fn._partial = True
+
+        call_args, kwargs = self._extract_call_args(kwargs)
+        
+        pruned_call_args = call_args
+        for k,v in Command._call_args.items():
+            try:
+                if pruned_call_args[k] == v:
+                    del pruned_call_args[k]
+            except KeyError: continue
+        
+        fn._partial_call_args.update(self._partial_call_args)
+        fn._partial_call_args.update(pruned_call_args)
+        fn._partial_baked_args.extend(self._partial_baked_args)
+        fn._partial_baked_args.extend(self._compile_args(args, kwargs))
+        return fn
+       
+    def __str__(self):
+        if IS_PY3: return self.__unicode__()
+        else: return unicode(self).encode(DEFAULT_ENCODING)
+        
+    def __eq__(self, other):
+        try: return str(self) == str(other)
+        except: return False
+
+    def __repr__(self):
+        return str(self)
+        
+    def __unicode__(self):
+        baked_args = " ".join(self._partial_baked_args)
+        if baked_args: baked_args = " " + baked_args
+        return self._path + baked_args
+
+    def __enter__(self):
+        self(_with=True)
+
+    def __exit__(self, typ, value, traceback):
+        Command._prepend_stack.pop()
+            
+    
+    def __call__(self, *args, **kwargs):
+        kwargs = kwargs.copy()
+        args = list(args)
+
+        cmd = []
+
+        # aggregate any 'with' contexts
+        call_args = Command._call_args.copy()
+        for prepend in self._prepend_stack:
+            # don't pass the 'with' call arg
+            pcall_args = prepend.call_args.copy()
+            try: del pcall_args["with"]
+            except: pass
+            
+            call_args.update(pcall_args)
+            cmd.extend(prepend.cmd)
+
+        cmd.append(self._path)
+        
+        # here we extract the special kwargs and override any
+        # special kwargs from the possibly baked command
+        tmp_call_args, kwargs = self._extract_call_args(kwargs, self._partial_call_args)
+        call_args.update(tmp_call_args)
+
+        if not isinstance(call_args["ok_code"], (tuple, list)):    
+            call_args["ok_code"] = [call_args["ok_code"]]
+            
+        
+        # check if we're piping via composition
+        stdin = call_args["in"]
+        if args:
+            first_arg = args.pop(0)
+            if isinstance(first_arg, RunningCommand):
+                # it makes sense that if the input pipe of a command is running
+                # in the background, then this command should run in the
+                # background as well
+                if first_arg.call_args["bg"]: call_args["bg"] = True
+                stdin = first_arg.process._pipe_queue
+                
+            else:
+                args.insert(0, first_arg)
+            
+        processed_args = self._compile_args(args, kwargs)
+
+        # makes sure our arguments are broken up correctly
+        split_args = self._partial_baked_args + processed_args
+
+        final_args = split_args
+
+        cmd.extend(final_args)
+
+
+        # stdout redirection
+        stdout = call_args["out"]
+        if stdout \
+            and not callable(stdout) \
+            and not hasattr(stdout, "write") \
+            and not isinstance(stdout, (cStringIO, StringIO)):
+            
+            stdout = open(str(stdout), "wb")
+        
+
+        # stderr redirection
+        stderr = call_args["err"]
+        if stderr and not callable(stderr) and not hasattr(stderr, "write") \
+            and not isinstance(stderr, (cStringIO, StringIO)):
+            stderr = open(str(stderr), "wb")
+            
+
+        return RunningCommand(cmd, call_args, stdin, stdout, stderr)
+
+
+
+
+# used in redirecting
+STDOUT = -1
+STDERR = -2
+
+
+
+# Process open = Popen
+# Open Process = OProc
+class OProc(object):
+    _procs_to_cleanup = set()
+    _registered_cleanup = False
+    _default_window_size = (24, 80)
+
+    def __init__(self, cmd, stdin, stdout, stderr, call_args,
+            persist=False, pipe=STDOUT):
+
+        self.call_args = call_args
+
+        self._single_tty = self.call_args["tty_in"] and self.call_args["tty_out"]
+
+        # this logic is a little convoluted, but basically this top-level
+        # if/else is for consolidating input and output TTYs into a single
+        # TTY.  this is the only way some secure programs like ssh will
+        # output correctly (is if stdout and stdin are both the same TTY)
+        if self._single_tty:
+            self._stdin_fd, self._slave_stdin_fd = pty.openpty()
+            
+            self._stdout_fd = self._stdin_fd
+            self._slave_stdout_fd = self._slave_stdin_fd
+            
+            self._stderr_fd = self._stdin_fd
+            self._slave_stderr_fd = self._slave_stdin_fd
+        
+        # do not consolidate stdin and stdout
+        else:
+            if self.call_args["tty_in"]:
+                self._slave_stdin_fd, self._stdin_fd = pty.openpty()
+            else:
+                self._slave_stdin_fd, self._stdin_fd = os.pipe()
+            
+            # tty_out is usually the default
+            if self.call_args["tty_out"]:
+                self._stdout_fd, self._slave_stdout_fd = pty.openpty()
+            else:
+                self._stdout_fd, self._slave_stdout_fd = os.pipe()
+                
+            # unless STDERR is going to STDOUT, it ALWAYS needs to be a pipe,
+            # and never a PTY.  the reason for this is not totally clear to me,
+            # but it has to do with the fact that if STDERR isn't set as the
+            # CTTY (because STDOUT is), the STDERR buffer won't always flush
+            # by the time the process exits, and the data will be lost.
+            # i've only seen this on OSX.
+            if stderr is not STDOUT:
+                self._stderr_fd, self._slave_stderr_fd = os.pipe()
+            
+        gc_enabled = gc.isenabled()
+        if gc_enabled: gc.disable()
+        self.pid = os.fork()
+
+
+        # child
+        if self.pid == 0:
+            # this piece of ugliness is due to a bug where we can lose output
+            # if we do os.close(self._slave_stdout_fd) in the parent after
+            # the child starts writing.
+            # see http://bugs.python.org/issue15898
+            if IS_OSX and IS_PY3: _time.sleep(0.01)
+            
+            os.setsid()
+            
+            if self.call_args["tty_out"]:
+                # set raw mode, so there isn't any weird translation of newlines
+                # to \r\n and other oddities.  we're not outputting to a terminal
+                # anyways
+                #
+                # we HAVE to do this here, and not in the parent thread, because
+                # we have to guarantee that this is set before the child process
+                # is run, and we can't do it twice.
+                tty.setraw(self._stdout_fd)
+                
+                
+            os.close(self._stdin_fd)
+            if not self._single_tty:
+                os.close(self._stdout_fd)
+                if stderr is not STDOUT: os.close(self._stderr_fd)                
+                    
+                    
+            if self.call_args["cwd"]: os.chdir(self.call_args["cwd"])
+            os.dup2(self._slave_stdin_fd, 0)
+            os.dup2(self._slave_stdout_fd, 1)
+            
+            # we're not directing stderr to stdout?  then set self._slave_stderr_fd to
+            # fd 2, the common stderr fd
+            if stderr is STDOUT: os.dup2(self._slave_stdout_fd, 2) 
+            else: os.dup2(self._slave_stderr_fd, 2)
+            
+            # don't inherit file descriptors
+            max_fd = resource.getrlimit(resource.RLIMIT_NOFILE)[0]
+            os.closerange(3, max_fd)
+                    
+
+            # set our controlling terminal
+            if self.call_args["tty_out"]:
+                tmp_fd = os.open(os.ttyname(1), os.O_RDWR)
+                os.close(tmp_fd)
+                    
+
+            if self.call_args["tty_out"]:
+                self.setwinsize(1)
+            
+            # actually execute the process
+            if self.call_args["env"] is None: os.execv(cmd[0], cmd)
+            else: os.execve(cmd[0], cmd, self.call_args["env"])
+
+            os._exit(255)
+
+        # parent
+        else:
+            if gc_enabled: gc.enable()
+            
+            if not OProc._registered_cleanup:
+                atexit.register(OProc._cleanup_procs)
+                OProc._registered_cleanup = True
+        
+        
+            self.started = _time.time()
+            self.cmd = cmd
+            self.exit_code = None
+            
+            self.stdin = stdin or Queue()
+            self._pipe_queue = Queue()
+        
+            # this is used to prevent a race condition when we're waiting for
+            # a process to end, and the OProc's internal threads are also checking
+            # for the processes's end
+            self._wait_lock = threading.Lock()
+        
+            # these are for aggregating the stdout and stderr.  we use a deque
+            # because we don't want to overflow
+            self._stdout = deque(maxlen=self.call_args["internal_bufsize"])
+            self._stderr = deque(maxlen=self.call_args["internal_bufsize"])
+            
+            if self.call_args["tty_in"]: self.setwinsize(self._stdin_fd)
+            
+            
+            self.log = Logger("process", repr(self))
+            
+            os.close(self._slave_stdin_fd)
+            if not self._single_tty:
+                os.close(self._slave_stdout_fd)
+                if stderr is not STDOUT: os.close(self._slave_stderr_fd)
+            
+            self.log.debug("started process")
+            if not persist: OProc._procs_to_cleanup.add(self)
+
+
+            if self.call_args["tty_in"]:
+                attr = termios.tcgetattr(self._stdin_fd)
+                attr[3] &= ~termios.ECHO  
+                termios.tcsetattr(self._stdin_fd, termios.TCSANOW, attr)
+
+            # this represents the connection from a Queue object (or whatever
+            # we're using to feed STDIN) to the process's STDIN fd
+            self._stdin_stream = StreamWriter("stdin", self, self._stdin_fd,
+                self.stdin, self.call_args["in_bufsize"])
+                           
+                        
+            stdout_pipe = None   
+            if pipe is STDOUT and not self.call_args["no_pipe"]:
+                stdout_pipe = self._pipe_queue
+            
+            # this represents the connection from a process's STDOUT fd to
+            # wherever it has to go, sometimes a pipe Queue (that we will use
+            # to pipe data to other processes), and also an internal deque
+            # that we use to aggregate all the output
+            save_stdout = not self.call_args["no_out"] and \
+                (self.call_args["tee"] in (True, "out") or stdout is None)
+            self._stdout_stream = StreamReader("stdout", self, self._stdout_fd, stdout,
+                self._stdout, self.call_args["out_bufsize"], stdout_pipe,
+                save_data=save_stdout)
+                
+                
+            if stderr is STDOUT or self._single_tty: self._stderr_stream = None 
+            else:
+                stderr_pipe = None
+                if pipe is STDERR and not self.call_args["no_pipe"]:
+                    stderr_pipe =  self._pipe_queue
+                       
+                save_stderr = not self.call_args["no_err"] and \
+                    (self.call_args["tee"] in ("err",) or stderr is None)
+                self._stderr_stream = StreamReader("stderr", self, self._stderr_fd, stderr,
+                    self._stderr, self.call_args["err_bufsize"], stderr_pipe,
+                    save_data=save_stderr)
+            
+            # start the main io threads
+            self._input_thread = self._start_thread(self.input_thread, self._stdin_stream)
+            self._output_thread = self._start_thread(self.output_thread, self._stdout_stream, self._stderr_stream)
+            
+            
+    def __repr__(self):
+        return "<Process %d %r>" % (self.pid, self.cmd[:500])        
+            
+
+    # also borrowed from pexpect.py
+    @staticmethod
+    def setwinsize(fd):
+        rows, cols = OProc._default_window_size
+        TIOCSWINSZ = getattr(termios, 'TIOCSWINSZ', -2146929561)
+        if TIOCSWINSZ == 2148037735: # L is not required in Python >= 2.2.
+            TIOCSWINSZ = -2146929561 # Same bits, but with sign.
+
+        s = struct.pack('HHHH', rows, cols, 0, 0)
+        fcntl.ioctl(fd, TIOCSWINSZ, s)
+
+
+    @staticmethod
+    def _start_thread(fn, *args):
+        thrd = threading.Thread(target=fn, args=args)
+        thrd.daemon = True
+        thrd.start()
+        return thrd
+    
+    def in_bufsize(self, buf):
+        self._stdin_stream.stream_bufferer.change_buffering(buf)
+                
+    def out_bufsize(self, buf):
+        self._stdout_stream.stream_bufferer.change_buffering(buf)
+    
+    def err_bufsize(self, buf):
+        if self._stderr_stream:
+            self._stderr_stream.stream_bufferer.change_buffering(buf)
+
+
+    def input_thread(self, stdin):
+        done = False
+        while not done and self.alive:
+            self.log.debug("%r ready for more input", stdin)
+            done = stdin.write()
+
+        stdin.close()
+            
+            
+    def output_thread(self, stdout, stderr):
+        readers = []
+        errors = []
+
+        if stdout is not None:
+            readers.append(stdout)
+            errors.append(stdout)
+        if stderr is not None:
+            readers.append(stderr)
+            errors.append(stderr)
+
+        while readers:
+            outputs, inputs, err = select.select(readers, [], errors, 0.1)
+
+            # stdout and stderr
+            for stream in outputs:
+                self.log.debug("%r ready to be read from", stream)
+                done = stream.read()
+                if done: readers.remove(stream)
+                
+            for stream in err:
+                pass
+            
+            # test if the process has been running too long
+            if self.call_args["timeout"]:
+                now = _time.time()
+                if now - self.started > self.call_args["timeout"]:
+                    self.log.debug("we've been running too long")
+                    self.kill()
+
+
+        # this is here because stdout may be the controlling TTY, and
+        # we can't close it until the process has ended, otherwise the
+        # child will get SIGHUP.  typically, if we've broken out of
+        # the above loop, and we're here, the process is just about to
+        # end, so it's probably ok to aggressively poll self.alive
+        #
+        # the other option to this would be to do the CTTY close from
+        # the method that does the actual os.waitpid() call, but the
+        # problem with that is that the above loop might still be
+        # running, and closing the fd will cause some operation to
+        # fail.  this is less complex than wrapping all the ops
+        # in the above loop with out-of-band fd-close exceptions
+        while self.alive: _time.sleep(0.001)
+        if stdout: stdout.close()
+        if stderr: stderr.close()
+
+
+    @property
+    def stdout(self):
+        return "".encode(self.call_args["encoding"]).join(self._stdout)
+    
+    @property
+    def stderr(self):
+        return "".encode(self.call_args["encoding"]).join(self._stderr)
+    
+    
+    def signal(self, sig):
+        self.log.debug("sending signal %d", sig)
+        try: os.kill(self.pid, sig)
+        except OSError: pass
+
+    def kill(self):
+        self.log.debug("killing")
+        self.signal(signal.SIGKILL)
+
+    def terminate(self):
+        self.log.debug("terminating")
+        self.signal(signal.SIGTERM)
+
+    @staticmethod
+    def _cleanup_procs():
+        for proc in OProc._procs_to_cleanup:
+            proc.kill()
+
+
+    def _handle_exit_code(self, exit_code):
+        # if we exited from a signal, let our exit code reflect that
+        if os.WIFSIGNALED(exit_code): return -os.WTERMSIG(exit_code)
+        # otherwise just give us a normal exit code
+        elif os.WIFEXITED(exit_code): return os.WEXITSTATUS(exit_code)
+        else: raise RuntimeError("Unknown child exit status!")
+
+    @property
+    def alive(self):
+        if self.exit_code is not None: return False
+         
+        # what we're doing here essentially is making sure that the main thread
+        # (or another thread), isn't calling .wait() on the process.  because
+        # .wait() calls os.waitpid(self.pid, 0), we can't do an os.waitpid
+        # here...because if we did, and the process exited while in this
+        # thread, the main thread's os.waitpid(self.pid, 0) would raise OSError
+        # (because the process ended in another thread).
+        #
+        # so essentially what we're doing is, using this lock, checking if
+        # we're calling .wait(), and if we are, let .wait() get the exit code
+        # and handle the status, otherwise let us do it.
+        acquired = self._wait_lock.acquire(False)
+        if not acquired:
+            if self.exit_code is not None: return False
+            return True
+         
+        try:
+            # WNOHANG is just that...we're calling waitpid without hanging...
+            # essentially polling the process
+            pid, exit_code = os.waitpid(self.pid, os.WNOHANG)
+            if pid == self.pid:
+                self.exit_code = self._handle_exit_code(exit_code)
+                return False
+             
+        # no child process   
+        except OSError: return False
+        else: return True
+        finally: self._wait_lock.release()
+            
+
+    def wait(self):
+        self.log.debug("acquiring wait lock to wait for completion")
+        with self._wait_lock:
+            self.log.debug("got wait lock")
+            
+            if self.exit_code is None:
+                self.log.debug("exit code not set, waiting on pid")
+                pid, exit_code = os.waitpid(self.pid, 0)
+                self.exit_code = self._handle_exit_code(exit_code)
+            else:
+                self.log.debug("exit code already set (%d), no need to wait", self.exit_code)
+            
+            self._input_thread.join()
+            self._output_thread.join()
+            
+            OProc._procs_to_cleanup.discard(self)
+            
+            return self.exit_code
+
+
+
+
+class DoneReadingStdin(Exception): pass
+class NoStdinData(Exception): pass
+
+
+
+# this guy is for reading from some input (the stream) and writing to our
+# opened process's stdin fd.  the stream can be a Queue, a callable, something
+# with the "read" method, a string, or an iterable
+class StreamWriter(object):
+    def __init__(self, name, process, stream, stdin, bufsize):
+        self.name = name
+        self.process = weakref.ref(process)
+        self.stream = stream
+        self.stdin = stdin
+        
+        self.log = Logger("streamwriter", repr(self))
+        
+        
+        self.stream_bufferer = StreamBufferer(self.process().call_args["encoding"],
+            bufsize)
+        
+        # determine buffering for reading from the input we set for stdin
+        if bufsize == 1: self.bufsize = 1024
+        elif bufsize == 0: self.bufsize = 1
+        else: self.bufsize = bufsize
+            
+        
+        if isinstance(stdin, Queue):
+            log_msg = "queue"
+            self.get_chunk = self.get_queue_chunk
+            
+        elif callable(stdin):
+            log_msg = "callable"
+            self.get_chunk = self.get_callable_chunk
+            
+        # also handles stringio
+        elif hasattr(stdin, "read"):
+            log_msg = "file descriptor"
+            self.get_chunk = self.get_file_chunk
+            
+        elif isinstance(stdin, basestring):
+            log_msg = "string"
+            
+            if bufsize == 1:
+                # TODO, make the split() be a generator
+                self.stdin = iter((c+"\n" for c in stdin.split("\n")))
+            else:
+                self.stdin = iter(stdin[i:i+self.bufsize] for i in range(0, len(stdin), self.bufsize))
+            self.get_chunk = self.get_iter_chunk
+            
+        else:
+            log_msg = "general iterable"
+            self.stdin = iter(stdin)
+            self.get_chunk = self.get_iter_chunk
+            
+        self.log.debug("parsed stdin as a %s", log_msg)
+        
+            
+    def __repr__(self):
+        return "<StreamWriter %s for %r>" % (self.name, self.process())
+    
+    def fileno(self):
+        return self.stream
+    
+    def get_queue_chunk(self):
+        try: chunk = self.stdin.get(True, 0.01)
+        except Empty: raise NoStdinData
+        if chunk is None: raise DoneReadingStdin
+        return chunk
+        
+    def get_callable_chunk(self):
+        try: return self.stdin()
+        except: raise DoneReadingStdin
+        
+    def get_iter_chunk(self):
+        try:
+            if IS_PY3: return self.stdin.__next__()
+            else: return self.stdin.next()
+        except StopIteration: raise DoneReadingStdin
+        
+    def get_file_chunk(self):
+        if self.stream_bufferer.type == 1: chunk = self.stdin.readline()
+        else: chunk = self.stdin.read(self.bufsize)
+        if not chunk: raise DoneReadingStdin
+        else: return chunk
+
+
+    # the return value answers the questions "are we done writing forever?"
+    def write(self):
+        # get_chunk may sometimes return bytes, and sometimes returns trings
+        # because of the nature of the different types of STDIN objects we
+        # support
+        try: chunk = self.get_chunk()
+        except DoneReadingStdin:
+            self.log.debug("done reading")
+                
+            if self.process().call_args["tty_in"]:
+                # EOF time
+                try: char = termios.tcgetattr(self.stream)[6][termios.VEOF]
+                except: char = chr(4).encode()
+                os.write(self.stream, char)
+            
+            return True
+        
+        except NoStdinData:
+            self.log.debug("received no data")
+            return False
+        
+        # if we're not bytes, make us bytes
+        if IS_PY3 and hasattr(chunk, "encode"):
+            chunk = chunk.encode(self.process().call_args["encoding"])
+        
+        for chunk in self.stream_bufferer.process(chunk):
+            self.log.debug("got chunk size %d: %r", len(chunk), chunk[:30])
+            
+            self.log.debug("writing chunk to process")
+            try:
+                os.write(self.stream, chunk)
+            except OSError:
+                self.log.debug("OSError writing stdin chunk")
+                return True
+        
+        
+    def close(self):
+        self.log.debug("closing, but flushing first")
+        chunk = self.stream_bufferer.flush()
+        self.log.debug("got chunk size %d to flush: %r", len(chunk), chunk[:30])
+        try:
+            if chunk: os.write(self.stream, chunk)
+            if not self.process().call_args["tty_in"]:
+                self.log.debug("we used a TTY, so closing the stream")
+                os.close(self.stream)
+        except OSError: pass
+        
+
+
+class StreamReader(object):
+    def __init__(self, name, process, stream, handler, buffer, bufsize,
+            pipe_queue=None, save_data=True):
+        self.name = name
+        self.process = weakref.ref(process)
+        self.stream = stream
+        self.buffer = buffer
+        self.save_data = save_data
+        self.encoding = process.call_args["encoding"]
+        self.decode_errors = process.call_args["decode_errors"]
+        
+        self.pipe_queue = None
+        if pipe_queue: self.pipe_queue = weakref.ref(pipe_queue)
+
+        self.log = Logger("streamreader", repr(self))
+        
+        self.stream_bufferer = StreamBufferer(self.encoding, bufsize,
+            self.decode_errors)
+        
+        # determine buffering
+        if bufsize == 1: self.bufsize = 1024
+        elif bufsize == 0: self.bufsize = 1 
+        else: self.bufsize = bufsize
+        
+        
+        # here we're determining the handler type by doing some basic checks
+        # on the handler object
+        self.handler = handler
+        if callable(handler): self.handler_type = "fn"
+        elif isinstance(handler, StringIO): self.handler_type = "stringio"
+        elif isinstance(handler, cStringIO):
+            self.handler_type = "cstringio"
+        elif hasattr(handler, "write"): self.handler_type = "fd"
+        else: self.handler_type = None
+        
+        
+        self.should_quit = False
+        
+        # here we choose how to call the callback, depending on how many
+        # arguments it takes.  the reason for this is to make it as easy as
+        # possible for people to use, without limiting them.  a new user will
+        # assume the callback takes 1 argument (the data).  as they get more
+        # advanced, they may want to terminate the process, or pass some stdin
+        # back, and will realize that they can pass a callback of more args
+        if self.handler_type == "fn":
+            implied_arg = 0
+            if inspect.ismethod(handler):
+                implied_arg = 1
+                num_args = len(inspect.getargspec(handler).args)
+            
+            else:
+                if inspect.isfunction(handler):
+                    num_args = len(inspect.getargspec(handler).args)
+                    
+                # is an object instance with __call__ method
+                else:
+                    implied_arg = 1
+                    num_args = len(inspect.getargspec(handler.__call__).args)
+                
+                
+            self.handler_args = ()
+            if num_args == implied_arg + 2:
+                self.handler_args = (self.process().stdin,)
+            elif num_args == implied_arg + 3:
+                self.handler_args = (self.process().stdin, self.process)
+                
+
+    def fileno(self):
+        return self.stream
+            
+    def __repr__(self):
+        return "<StreamReader %s for %r>" % (self.name, self.process())
+
+    def close(self):
+        chunk = self.stream_bufferer.flush()
+        self.log.debug("got chunk size %d to flush: %r",
+            len(chunk), chunk[:30])
+        if chunk: self.write_chunk(chunk)
+        
+        if self.handler_type == "fd" and hasattr(self.handler, "close"):
+            self.handler.flush()
+        
+        if self.pipe_queue and self.save_data: self.pipe_queue().put(None)
+        try: os.close(self.stream)
+        except OSError: pass
+
+
+    def write_chunk(self, chunk):
+        # in PY3, the chunk coming in will be bytes, so keep that in mind
+        
+        if self.handler_type == "fn" and not self.should_quit:
+            # try to use the encoding first, if that doesn't work, send
+            # the bytes, because it might be binary
+            try: to_handler = chunk.decode(self.encoding, self.decode_errors)
+            except UnicodeDecodeError: to_handler = chunk
+            
+            # this is really ugly, but we can't store self.process as one of
+            # the handler args in self.handler_args, the reason being is that
+            # it would create cyclic references, and prevent objects from
+            # being garbage collected.  so we're determining if this handler
+            # even requires self.process (by the argument count), and if it
+            # does, resolving the weakref to a hard reference and passing
+            # that into the handler
+            handler_args = self.handler_args
+            if len(self.handler_args) == 2:
+                handler_args = (self.handler_args[0], self.process())
+            self.should_quit = self.handler(to_handler, *handler_args)
+            
+        elif self.handler_type == "stringio":
+            self.handler.write(chunk.decode(self.encoding, self.decode_errors))
+
+        elif self.handler_type in ("cstringio", "fd"):
+            self.handler.write(chunk)
+            
+
+        if self.save_data:
+            self.buffer.append(chunk)
+            
+            if self.pipe_queue:
+                self.log.debug("putting chunk onto pipe: %r", chunk[:30])
+                self.pipe_queue().put(chunk)
+
+            
+    def read(self):
+        # if we're PY3, we're reading bytes, otherwise we're reading
+        # str
+        try: chunk = os.read(self.stream, self.bufsize)
+        except OSError as e:
+            self.log.debug("got errno %d, done reading", e.errno)
+            return True
+        if not chunk:
+            self.log.debug("got no chunk, done reading")
+            return True
+                
+        self.log.debug("got chunk size %d: %r", len(chunk), chunk[:30])
+        for chunk in self.stream_bufferer.process(chunk):
+            self.write_chunk(chunk)   
+    
+
+
+
+# this is used for feeding in chunks of stdout/stderr, and breaking it up into
+# chunks that will actually be put into the internal buffers.  for example, if
+# you have two processes, one being piped to the other, and you want that,
+# first process to feed lines of data (instead of the chunks however they
+# come in), OProc will use an instance of this class to chop up the data and
+# feed it as lines to be sent down the pipe
+class StreamBufferer(object):
+    def __init__(self, encoding=DEFAULT_ENCODING, buffer_type=1,
+            decode_errors="strict"):
+        # 0 for unbuffered, 1 for line, everything else for that amount
+        self.type = buffer_type
+        self.buffer = []
+        self.n_buffer_count = 0
+        self.encoding = encoding
+        self.decode_errors = decode_errors
+        
+        # this is for if we change buffering types.  if we change from line
+        # buffered to unbuffered, its very possible that our self.buffer list
+        # has data that was being saved up (while we searched for a newline).
+        # we need to use that up, so we don't lose it
+        self._use_up_buffer_first = False
+        
+        # the buffering lock is used because we might chance the buffering
+        # types from a different thread.  for example, if we have a stdout
+        # callback, we might use it to change the way stdin buffers.  so we
+        # lock
+        self._buffering_lock = threading.RLock()
+        self.log = Logger("stream_bufferer")
+        
+        
+    def change_buffering(self, new_type):
+        # TODO, when we stop supporting 2.6, make this a with context
+        self.log.debug("acquiring buffering lock for changing buffering")
+        self._buffering_lock.acquire()
+        self.log.debug("got buffering lock for changing buffering")
+        try:                
+            if new_type == 0: self._use_up_buffer_first = True
+                
+            self.type = new_type
+        finally:
+            self._buffering_lock.release()
+            self.log.debug("released buffering lock for changing buffering")
+            
+        
+    def process(self, chunk):
+        # MAKE SURE THAT THE INPUT IS PY3 BYTES
+        # THE OUTPUT IS ALWAYS PY3 BYTES
+        
+        # TODO, when we stop supporting 2.6, make this a with context
+        self.log.debug("acquiring buffering lock to process chunk (buffering: %d)", self.type)
+        self._buffering_lock.acquire()
+        self.log.debug("got buffering lock to process chunk (buffering: %d)", self.type)
+        try:
+            # we've encountered binary, permanently switch to N size buffering
+            # since matching on newline doesn't make sense anymore
+            if self.type == 1:
+                try: chunk.decode(self.encoding, self.decode_errors)
+                except:
+                    self.log.debug("detected binary data, changing buffering")
+                    self.change_buffering(1024)
+                
+            # unbuffered
+            if self.type == 0:
+                if self._use_up_buffer_first:
+                    self._use_up_buffer_first = False
+                    to_write = self.buffer
+                    self.buffer = []
+                    to_write.append(chunk)
+                    return to_write
+                
+                return [chunk]
+            
+            # line buffered
+            elif self.type == 1:
+                total_to_write = []
+                chunk = chunk.decode(self.encoding, self.decode_errors)
+                while True:
+                    newline = chunk.find("\n")
+                    if newline == -1: break
+                    
+                    chunk_to_write = chunk[:newline+1]
+                    if self.buffer:
+                        # this is ugly, but it's designed to take the existing
+                        # bytes buffer, join it together, tack on our latest
+                        # chunk, then convert the whole thing to a string.
+                        # it's necessary, i'm sure.  read the whole block to
+                        # see why.
+                        chunk_to_write = "".encode(self.encoding).join(self.buffer) \
+                            + chunk_to_write.encode(self.encoding)
+                        chunk_to_write = chunk_to_write.decode(self.encoding)
+                        
+                        self.buffer = []
+                        self.n_buffer_count = 0
+                    
+                    chunk = chunk[newline+1:]
+                    total_to_write.append(chunk_to_write.encode(self.encoding))
+                         
+                if chunk:
+                    self.buffer.append(chunk.encode(self.encoding))
+                    self.n_buffer_count += len(chunk)
+                return total_to_write
+              
+            # N size buffered  
+            else:
+                total_to_write = []
+                while True:
+                    overage = self.n_buffer_count + len(chunk) - self.type
+                    if overage >= 0:
+                        ret = "".encode(self.encoding).join(self.buffer) + chunk
+                        chunk_to_write = ret[:self.type]
+                        chunk = ret[self.type:]
+                        total_to_write.append(chunk_to_write)
+                        self.buffer = []
+                        self.n_buffer_count = 0
+                    else:
+                        self.buffer.append(chunk)
+                        self.n_buffer_count += len(chunk)
+                        break
+                return total_to_write
+        finally:
+            self._buffering_lock.release()
+            self.log.debug("released buffering lock for processing chunk (buffering: %d)", self.type)
+            
+
+    def flush(self):
+        self.log.debug("acquiring buffering lock for flushing buffer")
+        self._buffering_lock.acquire()
+        self.log.debug("got buffering lock for flushing buffer")
+        try:
+            ret = "".encode(self.encoding).join(self.buffer)
+            self.buffer = []
+            return ret
+        finally:
+            self._buffering_lock.release()
+            self.log.debug("released buffering lock for flushing buffer")
+    
+
+
+
+
+# this allows lookups to names that aren't found in the global scope to be
+# searched for as a program name.  for example, if "ls" isn't found in this
+# module's scope, we consider it a system program and try to find it.
+#
+# we use a dict instead of just a regular object as the base class because
+# the exec() statement used in this file requires the "globals" argument to
+# be a dictionary
+class Environment(dict):
+    def __init__(self, globs):
+        self.globs = globs
+        
+    def __setitem__(self, k, v):
+        self.globs[k] = v
+    
+    def __getitem__(self, k):
+        try: return self.globs[k]
+        except KeyError: pass
+        
+        # the only way we'd get to here is if we've tried to
+        # import * from a repl.  so, raise an exception, since
+        # that's really the only sensible thing to do
+        if k == "__all__":
+            raise ImportError("Cannot import * from sh. \
+Please import sh or import programs individually.")
+
+        # if we end with "_" just go ahead and skip searching
+        # our namespace for python stuff.  this was mainly for the
+        # command "id", which is a popular program for finding
+        # if a user exists, but also a python function for getting
+        # the address of an object.  so can call the python
+        # version by "id" and the program version with "id_"
+        if not k.endswith("_"):
+            # check if we're naming a dynamically generated ReturnCode exception
+            try: return rc_exc_cache[k]
+            except KeyError:
+                m = rc_exc_regex.match(k)
+                if m: return get_rc_exc(int(m.group(1)))
+                
+            # is it a builtin?
+            try: return getattr(self["__builtins__"], k)
+            except AttributeError: pass
+        elif not k.startswith("_"): k = k.rstrip("_")
+        
+        
+        # https://github.com/ipython/ipython/issues/2577
+        # https://github.com/amoffat/sh/issues/97#issuecomment-10610629
+        if k.startswith("__") and k.endswith("__"):
+            raise AttributeError
+        
+        # how about an environment variable?
+        try: return os.environ[k]
+        except KeyError: pass
+        
+        # is it a custom builtin?
+        builtin = getattr(self, "b_"+k, None)
+        if builtin: return builtin
+        
+        # it must be a command then
+        return Command._create(k)
+    
+    
+    # methods that begin with "b_" are custom builtins and will override any
+    # program that exists in our path.  this is useful for things like
+    # common shell builtins that people are used to, but which aren't actually
+    # full-fledged system binaries
+    
+    def b_cd(self, path):
+        os.chdir(path)
+        
+    def b_which(self, program):
+        return which(program)
+
+
+
+
+def run_repl(env):
+    banner = "\n>> sh v{version}\n>> https://github.com/amoffat/sh\n"
+    
+    print(banner.format(version=__version__))
+    while True:
+        try: line = raw_input("sh> ")
+        except (ValueError, EOFError): break
+            
+        try: exec(compile(line, "<dummy>", "single"), env, env)
+        except SystemExit: break
+        except: print(traceback.format_exc())
+
+    # cleans up our last line
+    print("")
+
+
+
+
+# this is a thin wrapper around THIS module (we patch sys.modules[__name__]).
+# this is in the case that the user does a "from sh import whatever"
+# in other words, they only want to import certain programs, not the whole
+# system PATH worth of commands.  in this case, we just proxy the
+# import lookup to our Environment class
+class SelfWrapper(ModuleType):
+    def __init__(self, self_module):
+        # this is super ugly to have to copy attributes like this,
+        # but it seems to be the only way to make reload() behave
+        # nicely.  if i make these attributes dynamic lookups in
+        # __getattr__, reload sometimes chokes in weird ways...
+        for attr in ["__builtins__", "__doc__", "__name__", "__package__"]:
+            setattr(self, attr, getattr(self_module, attr, None))
+
+        # python 3.2 (2.7 and 3.3 work fine) breaks on osx (not ubuntu)
+        # if we set this to None.  and 3.3 needs a value for __path__
+        self.__path__ = []
+        self.self_module = self_module
+        self.env = Environment(globals())
+        
+    def __setattr__(self, name, value):
+        if hasattr(self, "env"): self.env[name] = value
+        ModuleType.__setattr__(self, name, value)
+    
+    def __getattr__(self, name):
+        if name == "env": raise AttributeError
+        return self.env[name]
+
+
+
+
+
+# we're being run as a stand-alone script
+if __name__ == "__main__":
+    try: arg = sys.argv.pop(1)
+    except: arg = None
+
+    if arg == "test":
+        import subprocess
+
+        def run_test(version):
+            py_version = "python%s" % version
+            py_bin = which(py_version)
+
+            if py_bin:
+                print("Testing %s" % py_version.capitalize())
+                
+                p = subprocess.Popen([py_bin, os.path.join(THIS_DIR, "test.py")]
+                    + sys.argv[1:])
+                p.wait()
+            else:
+                print("Couldn't find %s, skipping" % py_version.capitalize())
+
+        versions = ("2.6", "2.7", "3.1", "3.2", "3.3")
+        for version in versions: run_test(version)
+
+    else:
+        env = Environment(globals())
+        run_repl(env)
+    
+# we're being imported from somewhere
+else:
+    self = sys.modules[__name__]
+    sys.modules[__name__] = SelfWrapper(self)