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diff --git a/doc/zmq_getsockopt.3 b/doc/zmq_getsockopt.3 deleted file mode 100644 index 0ee4d50..0000000 --- a/doc/zmq_getsockopt.3 +++ /dev/null @@ -1,1645 +0,0 @@ -'\" t -.\" Title: zmq_getsockopt -.\" Author: [see the "AUTHORS" section] -.\" Generator: DocBook XSL Stylesheets v1.76.1 <http://docbook.sf.net/> -.\" Date: 03/10/2014 -.\" Manual: 0MQ Manual -.\" Source: 0MQ 4.0.1 -.\" Language: English -.\" -.TH "ZMQ_GETSOCKOPT" "3" "03/10/2014" "0MQ 4\&.0\&.1" "0MQ Manual" -.\" ----------------------------------------------------------------- -.\" * Define some portability stuff -.\" ----------------------------------------------------------------- -.\" ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ -.\" http://bugs.debian.org/507673 -.\" http://lists.gnu.org/archive/html/groff/2009-02/msg00013.html -.\" ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ -.ie \n(.g .ds Aq \(aq -.el .ds Aq ' -.\" ----------------------------------------------------------------- -.\" * set default formatting -.\" ----------------------------------------------------------------- -.\" disable hyphenation -.nh -.\" disable justification (adjust text to left margin only) -.ad l -.\" ----------------------------------------------------------------- -.\" * MAIN CONTENT STARTS HERE * -.\" ----------------------------------------------------------------- -.SH "NAME" -zmq_getsockopt \- get 0MQ socket options -.SH "SYNOPSIS" -.sp -\fBint zmq_getsockopt (void \fR\fB\fI*socket\fR\fR\fB, int \fR\fB\fIoption_name\fR\fR\fB, void \fR\fB\fI*option_value\fR\fR\fB, size_t \fR\fB\fI*option_len\fR\fR\fB);\fR -.SH "DESCRIPTION" -.sp -The \fIzmq_getsockopt()\fR function shall retrieve the value for the option specified by the \fIoption_name\fR argument for the 0MQ socket pointed to by the \fIsocket\fR argument, and store it in the buffer pointed to by the \fIoption_value\fR argument\&. The \fIoption_len\fR argument is the size in bytes of the buffer pointed to by \fIoption_value\fR; upon successful completion \fIzmq_getsockopt()\fR shall modify the \fIoption_len\fR argument to indicate the actual size of the option value stored in the buffer\&. -.sp -The following options can be retrieved with the \fIzmq_getsockopt()\fR function: -.SS "ZMQ_TYPE: Retrieve socket type" -.sp -The \fIZMQ_TYPE\fR option shall retrieve the socket type for the specified \fIsocket\fR\&. The socket type is specified at socket creation time and cannot be modified afterwards\&. -.TS -tab(:); -lt lt -lt lt -lt lt -lt lt. -T{ -.sp -Option value type -T}:T{ -.sp -int -T} -T{ -.sp -Option value unit -T}:T{ -.sp -N/A -T} -T{ -.sp -Default value -T}:T{ -.sp -N/A -T} -T{ -.sp -Applicable socket types -T}:T{ -.sp -all -T} -.TE -.sp 1 -.SS "ZMQ_RCVMORE: More message data parts to follow" -.sp -The \fIZMQ_RCVMORE\fR option shall return True (1) if the message part last received from the \fIsocket\fR was a data part with more parts to follow\&. If there are no data parts to follow, this option shall return False (0)\&. -.sp -Refer to \fBzmq_send\fR(3) and \fBzmq_recv\fR(3) for a detailed description of multi\-part messages\&. -.TS -tab(:); -lt lt -lt lt -lt lt -lt lt. -T{ -.sp -Option value type -T}:T{ -.sp -int -T} -T{ -.sp -Option value unit -T}:T{ -.sp -boolean -T} -T{ -.sp -Default value -T}:T{ -.sp -N/A -T} -T{ -.sp -Applicable socket types -T}:T{ -.sp -all -T} -.TE -.sp 1 -.SS "ZMQ_SNDHWM: Retrieves high water mark for outbound messages" -.sp -The \fIZMQ_SNDHWM\fR option shall return the high water mark for outbound messages on the specified \fIsocket\fR\&. The high water mark is a hard limit on the maximum number of outstanding messages 0MQ shall queue in memory for any single peer that the specified \fIsocket\fR is communicating with\&. A value of zero means no limit\&. -.sp -If this limit has been reached the socket shall enter an exceptional state and depending on the socket type, 0MQ shall take appropriate action such as blocking or dropping sent messages\&. Refer to the individual socket descriptions in \fBzmq_socket\fR(3) for details on the exact action taken for each socket type\&. -.TS -tab(:); -lt lt -lt lt -lt lt -lt lt. -T{ -.sp -Option value type -T}:T{ -.sp -int -T} -T{ -.sp -Option value unit -T}:T{ -.sp -messages -T} -T{ -.sp -Default value -T}:T{ -.sp -1000 -T} -T{ -.sp -Applicable socket types -T}:T{ -.sp -all -T} -.TE -.sp 1 -.SS "ZMQ_RCVHWM: Retrieve high water mark for inbound messages" -.sp -The \fIZMQ_RCVHWM\fR option shall return the high water mark for inbound messages on the specified \fIsocket\fR\&. The high water mark is a hard limit on the maximum number of outstanding messages 0MQ shall queue in memory for any single peer that the specified \fIsocket\fR is communicating with\&. A value of zero means no limit\&. -.sp -If this limit has been reached the socket shall enter an exceptional state and depending on the socket type, 0MQ shall take appropriate action such as blocking or dropping sent messages\&. Refer to the individual socket descriptions in \fBzmq_socket\fR(3) for details on the exact action taken for each socket type\&. -.TS -tab(:); -lt lt -lt lt -lt lt -lt lt. -T{ -.sp -Option value type -T}:T{ -.sp -int -T} -T{ -.sp -Option value unit -T}:T{ -.sp -messages -T} -T{ -.sp -Default value -T}:T{ -.sp -1000 -T} -T{ -.sp -Applicable socket types -T}:T{ -.sp -all -T} -.TE -.sp 1 -.SS "ZMQ_AFFINITY: Retrieve I/O thread affinity" -.sp -The \fIZMQ_AFFINITY\fR option shall retrieve the I/O thread affinity for newly created connections on the specified \fIsocket\fR\&. -.sp -Affinity determines which threads from the 0MQ I/O thread pool associated with the socket\(cqs \fIcontext\fR shall handle newly created connections\&. A value of zero specifies no affinity, meaning that work shall be distributed fairly among all 0MQ I/O threads in the thread pool\&. For non\-zero values, the lowest bit corresponds to thread 1, second lowest bit to thread 2 and so on\&. For example, a value of 3 specifies that subsequent connections on \fIsocket\fR shall be handled exclusively by I/O threads 1 and 2\&. -.sp -See also \fBzmq_init\fR(3) for details on allocating the number of I/O threads for a specific \fIcontext\fR\&. -.TS -tab(:); -lt lt -lt lt -lt lt -lt lt. -T{ -.sp -Option value type -T}:T{ -.sp -uint64_t -T} -T{ -.sp -Option value unit -T}:T{ -.sp -N/A (bitmap) -T} -T{ -.sp -Default value -T}:T{ -.sp -0 -T} -T{ -.sp -Applicable socket types -T}:T{ -.sp -N/A -T} -.TE -.sp 1 -.SS "ZMQ_IDENTITY: Retrieve socket identity" -.sp -The \fIZMQ_IDENTITY\fR option shall retrieve the identity of the specified \fIsocket\fR\&. Socket identity is used only by request/reply pattern\&. Namely, it can be used in tandem with ROUTER socket to route messages to the peer with specific identity\&. -.sp -Identity should be at least one byte and at most 255 bytes long\&. Identities starting with binary zero are reserved for use by 0MQ infrastructure\&. -.TS -tab(:); -lt lt -lt lt -lt lt -lt lt. -T{ -.sp -Option value type -T}:T{ -.sp -binary data -T} -T{ -.sp -Option value unit -T}:T{ -.sp -N/A -T} -T{ -.sp -Default value -T}:T{ -.sp -NULL -T} -T{ -.sp -Applicable socket types -T}:T{ -.sp -ZMQ_REP, ZMQ_REQ, ZMQ_ROUTER, ZMQ_DEALER\&. -T} -.TE -.sp 1 -.SS "ZMQ_RATE: Retrieve multicast data rate" -.sp -The \fIZMQ_RATE\fR option shall retrieve the maximum send or receive data rate for multicast transports using the specified \fIsocket\fR\&. -.TS -tab(:); -lt lt -lt lt -lt lt -lt lt. -T{ -.sp -Option value type -T}:T{ -.sp -int -T} -T{ -.sp -Option value unit -T}:T{ -.sp -kilobits per second -T} -T{ -.sp -Default value -T}:T{ -.sp -100 -T} -T{ -.sp -Applicable socket types -T}:T{ -.sp -all, when using multicast transports -T} -.TE -.sp 1 -.SS "ZMQ_RECOVERY_IVL: Get multicast recovery interval" -.sp -The \fIZMQ_RECOVERY_IVL\fR option shall retrieve the recovery interval for multicast transports using the specified \fIsocket\fR\&. The recovery interval determines the maximum time in milliseconds that a receiver can be absent from a multicast group before unrecoverable data loss will occur\&. -.TS -tab(:); -lt lt -lt lt -lt lt -lt lt. -T{ -.sp -Option value type -T}:T{ -.sp -int -T} -T{ -.sp -Option value unit -T}:T{ -.sp -milliseconds -T} -T{ -.sp -Default value -T}:T{ -.sp -10000 -T} -T{ -.sp -Applicable socket types -T}:T{ -.sp -all, when using multicast transports -T} -.TE -.sp 1 -.SS "ZMQ_SNDBUF: Retrieve kernel transmit buffer size" -.sp -The \fIZMQ_SNDBUF\fR option shall retrieve the underlying kernel transmit buffer size for the specified \fIsocket\fR\&. A value of zero means that the OS default is in effect\&. For details refer to your operating system documentation for the \fISO_SNDBUF\fR socket option\&. -.TS -tab(:); -lt lt -lt lt -lt lt -lt lt. -T{ -.sp -Option value type -T}:T{ -.sp -int -T} -T{ -.sp -Option value unit -T}:T{ -.sp -bytes -T} -T{ -.sp -Default value -T}:T{ -.sp -0 -T} -T{ -.sp -Applicable socket types -T}:T{ -.sp -all -T} -.TE -.sp 1 -.SS "ZMQ_RCVBUF: Retrieve kernel receive buffer size" -.sp -The \fIZMQ_RCVBUF\fR option shall retrieve the underlying kernel receive buffer size for the specified \fIsocket\fR\&. A value of zero means that the OS default is in effect\&. For details refer to your operating system documentation for the \fISO_RCVBUF\fR socket option\&. -.TS -tab(:); -lt lt -lt lt -lt lt -lt lt. -T{ -.sp -Option value type -T}:T{ -.sp -int -T} -T{ -.sp -Option value unit -T}:T{ -.sp -bytes -T} -T{ -.sp -Default value -T}:T{ -.sp -0 -T} -T{ -.sp -Applicable socket types -T}:T{ -.sp -all -T} -.TE -.sp 1 -.SS "ZMQ_LINGER: Retrieve linger period for socket shutdown" -.sp -The \fIZMQ_LINGER\fR option shall retrieve the linger period for the specified \fIsocket\fR\&. The linger period determines how long pending messages which have yet to be sent to a peer shall linger in memory after a socket is closed with \fBzmq_close\fR(3), and further affects the termination of the socket\(cqs context with \fBzmq_term\fR(3)\&. The following outlines the different behaviours: -.sp -.RS 4 -.ie n \{\ -\h'-04'\(bu\h'+03'\c -.\} -.el \{\ -.sp -1 -.IP \(bu 2.3 -.\} -The default value of -\fI\-1\fR -specifies an infinite linger period\&. Pending messages shall not be discarded after a call to -\fIzmq_close()\fR; attempting to terminate the socket\(cqs context with -\fIzmq_term()\fR -shall block until all pending messages have been sent to a peer\&. -.RE -.sp -.RS 4 -.ie n \{\ -\h'-04'\(bu\h'+03'\c -.\} -.el \{\ -.sp -1 -.IP \(bu 2.3 -.\} -The value of -\fI0\fR -specifies no linger period\&. Pending messages shall be discarded immediately when the socket is closed with -\fIzmq_close()\fR\&. -.RE -.sp -.RS 4 -.ie n \{\ -\h'-04'\(bu\h'+03'\c -.\} -.el \{\ -.sp -1 -.IP \(bu 2.3 -.\} -Positive values specify an upper bound for the linger period in milliseconds\&. Pending messages shall not be discarded after a call to -\fIzmq_close()\fR; attempting to terminate the socket\(cqs context with -\fIzmq_term()\fR -shall block until either all pending messages have been sent to a peer, or the linger period expires, after which any pending messages shall be discarded\&. -.TS -tab(:); -lt lt -lt lt -lt lt -lt lt. -T{ -Option value type -T}:T{ -int -T} -T{ -Option value unit -T}:T{ -milliseconds -T} -T{ -Default value -T}:T{ -\-1 (infinite) -T} -T{ -Applicable socket types -T}:T{ -all -T} -.TE -.sp 1 -.RE -.SS "ZMQ_RECONNECT_IVL: Retrieve reconnection interval" -.sp -The \fIZMQ_RECONNECT_IVL\fR option shall retrieve the initial reconnection interval for the specified \fIsocket\fR\&. The reconnection interval is the period 0MQ shall wait between attempts to reconnect disconnected peers when using connection\-oriented transports\&. The value \-1 means no reconnection\&. -.if n \{\ -.sp -.\} -.RS 4 -.it 1 an-trap -.nr an-no-space-flag 1 -.nr an-break-flag 1 -.br -.ps +1 -\fBNote\fR -.ps -1 -.br -.sp -The reconnection interval may be randomized by 0MQ to prevent reconnection storms in topologies with a large number of peers per socket\&. -.sp .5v -.RE -.TS -tab(:); -lt lt -lt lt -lt lt -lt lt. -T{ -.sp -Option value type -T}:T{ -.sp -int -T} -T{ -.sp -Option value unit -T}:T{ -.sp -milliseconds -T} -T{ -.sp -Default value -T}:T{ -.sp -100 -T} -T{ -.sp -Applicable socket types -T}:T{ -.sp -all, only for connection\-oriented transports -T} -.TE -.sp 1 -.SS "ZMQ_RECONNECT_IVL_MAX: Retrieve maximum reconnection interval" -.sp -The \fIZMQ_RECONNECT_IVL_MAX\fR option shall retrieve the maximum reconnection interval for the specified \fIsocket\fR\&. This is the maximum period 0MQ shall wait between attempts to reconnect\&. On each reconnect attempt, the previous interval shall be doubled untill ZMQ_RECONNECT_IVL_MAX is reached\&. This allows for exponential backoff strategy\&. Default value means no exponential backoff is performed and reconnect interval calculations are only based on ZMQ_RECONNECT_IVL\&. -.if n \{\ -.sp -.\} -.RS 4 -.it 1 an-trap -.nr an-no-space-flag 1 -.nr an-break-flag 1 -.br -.ps +1 -\fBNote\fR -.ps -1 -.br -.sp -Values less than ZMQ_RECONNECT_IVL will be ignored\&. -.sp .5v -.RE -.TS -tab(:); -lt lt -lt lt -lt lt -lt lt. -T{ -.sp -Option value type -T}:T{ -.sp -int -T} -T{ -.sp -Option value unit -T}:T{ -.sp -milliseconds -T} -T{ -.sp -Default value -T}:T{ -.sp -0 (only use ZMQ_RECONNECT_IVL) -T} -T{ -.sp -Applicable socket types -T}:T{ -.sp -all, only for connection\-oriented transport -T} -.TE -.sp 1 -.SS "ZMQ_BACKLOG: Retrieve maximum length of the queue of outstanding connections" -.sp -The \fIZMQ_BACKLOG\fR option shall retrieve the maximum length of the queue of outstanding peer connections for the specified \fIsocket\fR; this only applies to connection\-oriented transports\&. For details refer to your operating system documentation for the \fIlisten\fR function\&. -.TS -tab(:); -lt lt -lt lt -lt lt -lt lt. -T{ -.sp -Option value type -T}:T{ -.sp -int -T} -T{ -.sp -Option value unit -T}:T{ -.sp -connections -T} -T{ -.sp -Default value -T}:T{ -.sp -100 -T} -T{ -.sp -Applicable socket types -T}:T{ -.sp -all, only for connection\-oriented transports -T} -.TE -.sp 1 -.SS "ZMQ_MAXMSGSIZE: Maximum acceptable inbound message size" -.sp -The option shall retrieve limit for the inbound messages\&. If a peer sends a message larger than ZMQ_MAXMSGSIZE it is disconnected\&. Value of \-1 means \fIno limit\fR\&. -.TS -tab(:); -lt lt -lt lt -lt lt -lt lt. -T{ -.sp -Option value type -T}:T{ -.sp -int64_t -T} -T{ -.sp -Option value unit -T}:T{ -.sp -bytes -T} -T{ -.sp -Default value -T}:T{ -.sp -\-1 -T} -T{ -.sp -Applicable socket types -T}:T{ -.sp -all -T} -.TE -.sp 1 -.SS "ZMQ_MULTICAST_HOPS: Maximum network hops for multicast packets" -.sp -The option shall retrieve time\-to\-live used for outbound multicast packets\&. The default of 1 means that the multicast packets don\(cqt leave the local network\&. -.TS -tab(:); -lt lt -lt lt -lt lt -lt lt. -T{ -.sp -Option value type -T}:T{ -.sp -int -T} -T{ -.sp -Option value unit -T}:T{ -.sp -network hops -T} -T{ -.sp -Default value -T}:T{ -.sp -1 -T} -T{ -.sp -Applicable socket types -T}:T{ -.sp -all, when using multicast transports -T} -.TE -.sp 1 -.SS "ZMQ_RCVTIMEO: Maximum time before a socket operation returns with EAGAIN" -.sp -Retrieve the timeout for recv operation on the socket\&. If the value is 0, \fIzmq_recv(3)\fR will return immediately, with a EAGAIN error if there is no message to receive\&. If the value is \-1, it will block until a message is available\&. For all other values, it will wait for a message for that amount of time before returning with an EAGAIN error\&. -.TS -tab(:); -lt lt -lt lt -lt lt -lt lt. -T{ -.sp -Option value type -T}:T{ -.sp -int -T} -T{ -.sp -Option value unit -T}:T{ -.sp -milliseconds -T} -T{ -.sp -Default value -T}:T{ -.sp -\-1 (infinite) -T} -T{ -.sp -Applicable socket types -T}:T{ -.sp -all -T} -.TE -.sp 1 -.SS "ZMQ_SNDTIMEO: Maximum time before a socket operation returns with EAGAIN" -.sp -Retrieve the timeout for send operation on the socket\&. If the value is 0, \fIzmq_send(3)\fR will return immediately, with a EAGAIN error if the message cannot be sent\&. If the value is \-1, it will block until the message is sent\&. For all other values, it will try to send the message for that amount of time before returning with an EAGAIN error\&. -.TS -tab(:); -lt lt -lt lt -lt lt -lt lt. -T{ -.sp -Option value type -T}:T{ -.sp -int -T} -T{ -.sp -Option value unit -T}:T{ -.sp -milliseconds -T} -T{ -.sp -Default value -T}:T{ -.sp -\-1 (infinite) -T} -T{ -.sp -Applicable socket types -T}:T{ -.sp -all -T} -.TE -.sp 1 -.SS "ZMQ_IPV6: Retrieve IPv6 socket status" -.sp -Retrieve the IPv6 option for the socket\&. A value of 1 means IPv6 is enabled on the socket, while 0 means the socket will use only IPv4\&. When IPv6 is enabled the socket will connect to, or accept connections from, both IPv4 and IPv6 hosts\&. -.TS -tab(:); -lt lt -lt lt -lt lt -lt lt. -T{ -.sp -Option value type -T}:T{ -.sp -int -T} -T{ -.sp -Option value unit -T}:T{ -.sp -boolean -T} -T{ -.sp -Default value -T}:T{ -.sp -0 (false) -T} -T{ -.sp -Applicable socket types -T}:T{ -.sp -all, when using TCP transports\&. -T} -.TE -.sp 1 -.SS "ZMQ_IPV4ONLY: Retrieve IPv4\-only socket override status" -.sp -Retrieve the IPv4\-only option for the socket\&. This option is deprecated\&. Please use the ZMQ_IPV6 option\&. -.TS -tab(:); -lt lt -lt lt -lt lt -lt lt. -T{ -.sp -Option value type -T}:T{ -.sp -int -T} -T{ -.sp -Option value unit -T}:T{ -.sp -boolean -T} -T{ -.sp -Default value -T}:T{ -.sp -1 (true) -T} -T{ -.sp -Applicable socket types -T}:T{ -.sp -all, when using TCP transports\&. -T} -.TE -.sp 1 -.SS "ZMQ_IMMEDIATE: Retrieve attach\-on\-connect value" -.sp -Retrieve the state of the attach on connect value\&. If set to 1, will delay the attachment of a pipe on connect until the underlying connection has completed\&. This will cause the socket to block if there are no other connections, but will prevent queues from filling on pipes awaiting connection\&. -.TS -tab(:); -lt lt -lt lt -lt lt -lt lt. -T{ -.sp -Option value type -T}:T{ -.sp -int -T} -T{ -.sp -Option value unit -T}:T{ -.sp -boolean -T} -T{ -.sp -Default value -T}:T{ -.sp -0 (false) -T} -T{ -.sp -Applicable socket types -T}:T{ -.sp -all, primarily when using TCP/IPC transports\&. -T} -.TE -.sp 1 -.SS "ZMQ_FD: Retrieve file descriptor associated with the socket" -.sp -The \fIZMQ_FD\fR option shall retrieve the file descriptor associated with the specified \fIsocket\fR\&. The returned file descriptor can be used to integrate the socket into an existing event loop; the 0MQ library shall signal any pending events on the socket in an \fIedge\-triggered\fR fashion by making the file descriptor become ready for reading\&. -.if n \{\ -.sp -.\} -.RS 4 -.it 1 an-trap -.nr an-no-space-flag 1 -.nr an-break-flag 1 -.br -.ps +1 -\fBNote\fR -.ps -1 -.br -.sp -The ability to read from the returned file descriptor does not necessarily indicate that messages are available to be read from, or can be written to, the underlying socket; applications must retrieve the actual event state with a subsequent retrieval of the \fIZMQ_EVENTS\fR option\&. -.sp .5v -.RE -.if n \{\ -.sp -.\} -.RS 4 -.it 1 an-trap -.nr an-no-space-flag 1 -.nr an-break-flag 1 -.br -.ps +1 -\fBNote\fR -.ps -1 -.br -.sp -The returned file descriptor is also used internally by the \fIzmq_send\fR and \fIzmq_recv\fR functions\&. As the descriptor is edge triggered, applications must update the state of \fIZMQ_EVENTS\fR after each invocation of \fIzmq_send\fR or \fIzmq_recv\fR\&.To be more explicit: after calling \fIzmq_send\fR the socket may become readable (and vice versa) without triggering a read event on the file descriptor\&. -.sp .5v -.RE -.if n \{\ -.sp -.\} -.RS 4 -.it 1 an-trap -.nr an-no-space-flag 1 -.nr an-break-flag 1 -.br -.ps +1 -\fBCaution\fR -.ps -1 -.br -.sp -The returned file descriptor is intended for use with a \fIpoll\fR or similar system call only\&. Applications must never attempt to read or write data to it directly, neither should they try to close it\&. -.sp .5v -.RE -.TS -tab(:); -lt lt -lt lt -lt lt -lt lt. -T{ -.sp -Option value type -T}:T{ -.sp -int on POSIX systems, SOCKET on Windows -T} -T{ -.sp -Option value unit -T}:T{ -.sp -N/A -T} -T{ -.sp -Default value -T}:T{ -.sp -N/A -T} -T{ -.sp -Applicable socket types -T}:T{ -.sp -all -T} -.TE -.sp 1 -.SS "ZMQ_EVENTS: Retrieve socket event state" -.sp -The \fIZMQ_EVENTS\fR option shall retrieve the event state for the specified \fIsocket\fR\&. The returned value is a bit mask constructed by OR\(cqing a combination of the following event flags: -.PP -\fBZMQ_POLLIN\fR -.RS 4 -Indicates that at least one message may be received from the specified socket without blocking\&. -.RE -.PP -\fBZMQ_POLLOUT\fR -.RS 4 -Indicates that at least one message may be sent to the specified socket without blocking\&. -.RE -.sp -The combination of a file descriptor returned by the \fIZMQ_FD\fR option being ready for reading but no actual events returned by a subsequent retrieval of the \fIZMQ_EVENTS\fR option is valid; applications should simply ignore this case and restart their polling operation/event loop\&. -.TS -tab(:); -lt lt -lt lt -lt lt -lt lt. -T{ -.sp -Option value type -T}:T{ -.sp -int -T} -T{ -.sp -Option value unit -T}:T{ -.sp -N/A (flags) -T} -T{ -.sp -Default value -T}:T{ -.sp -N/A -T} -T{ -.sp -Applicable socket types -T}:T{ -.sp -all -T} -.TE -.sp 1 -.SS "ZMQ_LAST_ENDPOINT: Retrieve the last endpoint set" -.sp -The \fIZMQ_LAST_ENDPOINT\fR option shall retrieve the last endpoint bound for TCP and IPC transports\&. The returned value will be a string in the form of a ZMQ DSN\&. Note that if the TCP host is INADDR_ANY, indicated by a *, then the returned address will be 0\&.0\&.0\&.0 (for IPv4)\&. -.TS -tab(:); -lt lt -lt lt -lt lt -lt lt. -T{ -.sp -Option value type -T}:T{ -.sp -NULL\-terminated character string -T} -T{ -.sp -Option value unit -T}:T{ -.sp -N/A -T} -T{ -.sp -Default value -T}:T{ -.sp -NULL -T} -T{ -.sp -Applicable socket types -T}:T{ -.sp -all, when binding TCP or IPC transports -T} -.TE -.sp 1 -.SS "ZMQ_TCP_KEEPALIVE: Override SO_KEEPALIVE socket option" -.sp -Override \fISO_KEEPALIVE\fR socket option(where supported by OS)\&. The default value of \-1 means to skip any overrides and leave it to OS default\&. -.TS -tab(:); -lt lt -lt lt -lt lt -lt lt. -T{ -.sp -Option value type -T}:T{ -.sp -int -T} -T{ -.sp -Option value unit -T}:T{ -.sp -\-1,0,1 -T} -T{ -.sp -Default value -T}:T{ -.sp -\-1 (leave to OS default) -T} -T{ -.sp -Applicable socket types -T}:T{ -.sp -all, when using TCP transports\&. -T} -.TE -.sp 1 -.SS "ZMQ_TCP_KEEPALIVE_IDLE: Override TCP_KEEPCNT(or TCP_KEEPALIVE on some OS)" -.sp -Override \fITCP_KEEPCNT\fR(or \fITCP_KEEPALIVE\fR on some OS) socket option (where supported by OS)\&. The default value of \-1 means to skip any overrides and leave it to OS default\&. -.TS -tab(:); -lt lt -lt lt -lt lt -lt lt. -T{ -.sp -Option value type -T}:T{ -.sp -int -T} -T{ -.sp -Option value unit -T}:T{ -.sp -\-1,>0 -T} -T{ -.sp -Default value -T}:T{ -.sp -\-1 (leave to OS default) -T} -T{ -.sp -Applicable socket types -T}:T{ -.sp -all, when using TCP transports\&. -T} -.TE -.sp 1 -.SS "ZMQ_TCP_KEEPALIVE_CNT: Override TCP_KEEPCNT socket option" -.sp -Override \fITCP_KEEPCNT\fR socket option(where supported by OS)\&. The default value of \-1 means to skip any overrides and leave it to OS default\&. -.TS -tab(:); -lt lt -lt lt -lt lt -lt lt. -T{ -.sp -Option value type -T}:T{ -.sp -int -T} -T{ -.sp -Option value unit -T}:T{ -.sp -\-1,>0 -T} -T{ -.sp -Default value -T}:T{ -.sp -\-1 (leave to OS default) -T} -T{ -.sp -Applicable socket types -T}:T{ -.sp -all, when using TCP transports\&. -T} -.TE -.sp 1 -.SS "ZMQ_TCP_KEEPALIVE_INTVL: Override TCP_KEEPINTVL socket option" -.sp -Override \fITCP_KEEPINTVL\fR socket option(where supported by OS)\&. The default value of \-1 means to skip any overrides and leave it to OS default\&. -.TS -tab(:); -lt lt -lt lt -lt lt -lt lt. -T{ -.sp -Option value type -T}:T{ -.sp -int -T} -T{ -.sp -Option value unit -T}:T{ -.sp -\-1,>0 -T} -T{ -.sp -Default value -T}:T{ -.sp -\-1 (leave to OS default) -T} -T{ -.sp -Applicable socket types -T}:T{ -.sp -all, when using TCP transports\&. -T} -.TE -.sp 1 -.SS "ZMQ_MECHANISM: Retrieve current security mechanism" -.sp -The \fIZMQ_MECHANISM\fR option shall retrieve the current security mechanism for the socket\&. -.TS -tab(:); -lt lt -lt lt -lt lt -lt lt. -T{ -.sp -Option value type -T}:T{ -.sp -int -T} -T{ -.sp -Option value unit -T}:T{ -.sp -ZMQ_NULL, ZMQ_PLAIN, or ZMQ_CURVE -T} -T{ -.sp -Default value -T}:T{ -.sp -ZMQ_NULL -T} -T{ -.sp -Applicable socket types -T}:T{ -.sp -all, when using TCP or IPC transports -T} -.TE -.sp 1 -.SS "ZMQ_PLAIN_SERVER: Retrieve current PLAIN server role" -.sp -Returns the \fIZMQ_PLAIN_SERVER\fR option, if any, previously set on the socket\&. -.TS -tab(:); -lt lt -lt lt -lt lt -lt lt. -T{ -.sp -Option value type -T}:T{ -.sp -int -T} -T{ -.sp -Option value unit -T}:T{ -.sp -0, 1 -T} -T{ -.sp -Default value -T}:T{ -.sp -int -T} -T{ -.sp -Applicable socket types -T}:T{ -.sp -all, when using TCP or IPC transports -T} -.TE -.sp 1 -.SS "ZMQ_PLAIN_USERNAME: Retrieve current PLAIN username" -.sp -The \fIZMQ_PLAIN_USERNAME\fR option shall retrieve the last username set for the PLAIN security mechanism\&. The returned value shall be a NULL\-terminated string and MAY be empty\&. The returned size SHALL include the terminating null byte\&. -.TS -tab(:); -lt lt -lt lt -lt lt -lt lt. -T{ -.sp -Option value type -T}:T{ -.sp -NULL\-terminated character string -T} -T{ -.sp -Option value unit -T}:T{ -.sp -N/A -T} -T{ -.sp -Default value -T}:T{ -.sp -null string -T} -T{ -.sp -Applicable socket types -T}:T{ -.sp -all, when using TCP or IPC transports -T} -.TE -.sp 1 -.SS "ZMQ_PLAIN_PASSWORD: Retrieve current password" -.sp -The \fIZMQ_PLAIN_PASSWORD\fR option shall retrieve the last password set for the PLAIN security mechanism\&. The returned value shall be a NULL\-terminated string and MAY be empty\&. The returned size SHALL include the terminating null byte\&. -.TS -tab(:); -lt lt -lt lt -lt lt -lt lt. -T{ -.sp -Option value type -T}:T{ -.sp -NULL\-terminated character string -T} -T{ -.sp -Option value unit -T}:T{ -.sp -N/A -T} -T{ -.sp -Default value -T}:T{ -.sp -null string -T} -T{ -.sp -Applicable socket types -T}:T{ -.sp -all, when using TCP or IPC transports -T} -.TE -.sp 1 -.SS "ZMQ_CURVE_PUBLICKEY: Retrieve current CURVE public key" -.sp -Retrieves the current long term public key for the socket\&. You can provide either a 32 byte buffer, to retrieve the binary key value, or a 41 byte buffer, to retrieve the key in a printable Z85 format\&. NOTE: to fetch a printable key, the buffer must be 41 bytes large to hold the 40\-char key value and one null byte\&. -.TS -tab(:); -lt lt -lt lt -lt lt -lt lt. -T{ -.sp -Option value type -T}:T{ -.sp -binary data or Z85 text string -T} -T{ -.sp -Option value size -T}:T{ -.sp -32 or 41 -T} -T{ -.sp -Default value -T}:T{ -.sp -null -T} -T{ -.sp -Applicable socket types -T}:T{ -.sp -all, when using TCP transport -T} -.TE -.sp 1 -.SS "ZMQ_CURVE_SECRETKEY: Retrieve current CURVE secret key" -.sp -Retrieves the current long term secret key for the socket\&. You can provide either a 32 byte buffer, to retrieve the binary key value, or a 41 byte buffer, to retrieve the key in a printable Z85 format\&. -.TS -tab(:); -lt lt -lt lt -lt lt -lt lt. -T{ -.sp -Option value type -T}:T{ -.sp -binary data or Z85 text string -T} -T{ -.sp -Option value size -T}:T{ -.sp -32 or 41 -T} -T{ -.sp -Default value -T}:T{ -.sp -null -T} -T{ -.sp -Applicable socket types -T}:T{ -.sp -all, when using TCP transport -T} -.TE -.sp 1 -.SS "ZMQ_CURVE_SERVERKEY: Retrieve current CURVE server key" -.sp -Retrieves the current server key for the client socket\&. You can provide either a 32 byte buffer, to retrieve the binary key value, or a 40 byte buffer, to retrieve the key in a printable Z85 format\&. -.TS -tab(:); -lt lt -lt lt -lt lt -lt lt. -T{ -.sp -Option value type -T}:T{ -.sp -binary data or Z85 text string -T} -T{ -.sp -Option value size -T}:T{ -.sp -32 or 41 -T} -T{ -.sp -Default value -T}:T{ -.sp -null -T} -T{ -.sp -Applicable socket types -T}:T{ -.sp -all, when using TCP transport -T} -.TE -.sp 1 -.SS "ZMQ_ZAP_DOMAIN: Retrieve RFC 27 authentication domain" -.sp -The \fIZMQ_ZAP_DOMAIN\fR option shall retrieve the last ZAP domain set for the socket\&. The returned value shall be a NULL\-terminated string and MAY be empty\&. The returned size SHALL include the terminating null byte\&. -.TS -tab(:); -lt lt -lt lt -lt lt -lt lt. -T{ -.sp -Option value type -T}:T{ -.sp -character string -T} -T{ -.sp -Option value unit -T}:T{ -.sp -N/A -T} -T{ -.sp -Default value -T}:T{ -.sp -not set -T} -T{ -.sp -Applicable socket types -T}:T{ -.sp -all, when using TCP transport -T} -.TE -.sp 1 -.SH "RETURN VALUE" -.sp -The \fIzmq_getsockopt()\fR function shall return zero if successful\&. Otherwise it shall return \-1 and set \fIerrno\fR to one of the values defined below\&. -.SH "ERRORS" -.PP -\fBEINVAL\fR -.RS 4 -The requested option -\fIoption_name\fR -is unknown, or the requested -\fIoption_len\fR -or -\fIoption_value\fR -is invalid, or the size of the buffer pointed to by -\fIoption_value\fR, as specified by -\fIoption_len\fR, is insufficient for storing the option value\&. -.RE -.PP -\fBETERM\fR -.RS 4 -The 0MQ -\fIcontext\fR -associated with the specified -\fIsocket\fR -was terminated\&. -.RE -.PP -\fBENOTSOCK\fR -.RS 4 -The provided -\fIsocket\fR -was invalid\&. -.RE -.PP -\fBEINTR\fR -.RS 4 -The operation was interrupted by delivery of a signal\&. -.RE -.SH "EXAMPLE" -.PP -\fBRetrieving the high water mark for outgoing messages\fR. -.sp -.if n \{\ -.RS 4 -.\} -.nf -/* Retrieve high water mark into sndhwm */ -int sndhwm; -size_t sndhwm_size = sizeof (sndhwm); -rc = zmq_getsockopt (socket, ZMQ_SNDHWM, &sndhwm, &sndhwm_size); -assert (rc == 0); -.fi -.if n \{\ -.RE -.\} -.sp -.SH "SEE ALSO" -.sp -\fBzmq_setsockopt\fR(3) \fBzmq_socket\fR(3) \fBzmq\fR(7) -.SH "AUTHORS" -.sp -This page was written by the 0MQ community\&. To make a change please read the 0MQ Contribution Policy at \m[blue]\fBhttp://www\&.zeromq\&.org/docs:contributing\fR\m[]\&. |