Section 3: library functions
zmq_unbind – Stop accepting connections on a socket Synopsis int zmq_unbind(void *socket, const char *endpoint); Description The zmq_unbind() function shall unbind a socket specified by the socket argument from the endpoint specified by the endpoint argument. The endpoint argument is as described in zmq_bind(3) Unbinding wild-card addres from a socket When wild-card * endpoint (described…
zmq_strerror – get 0MQ error message string Synopsis const char *zmq_strerror(int errnum); Description The zmq_strerror() function shall return a pointer to an error message string corresponding to the error number specified by the errnum argument. As 0MQ defines additional error numbers over and above those defined by the operating system, applications should use zmq_strerror() in…
zmq_socket_monitor – monitor socket events Synopsis int zmq_socket_monitor(void *socket, char *endpoint, int events); Description The zmq_socket_monitor() method lets an application thread track socket events (like connects) on a ZeroMQ socket. Each call to this method creates a ZMQ_PAIR socket and binds that to the specified inproc:// endpoint. To collect the socket events, you must create…
zmq_socket – create 0MQ socket Synopsis void *zmq_socket(void *context, int type); Description The zmq_socket() function shall create a 0MQ socket within the specified context and return an opaque handle to the newly created socket. The type argument specifies the socket type, which determines the semantics of communication over the socket. The newly created socket is…
zmq_setsockopt – set 0MQ socket options Synopsis int zmq_setsockopt(void *socket, int option_name, const void *option_value, size_t option_len); Caution: All options, with the exception of ZMQ_SUBSCRIBE, ZMQ_UNSUBSCRIBE, ZMQ_LINGER, ZMQ_ROUTER_HANDOVER, ZMQ_ROUTER_MANDATORY, ZMQ_PROBE_ROUTER, ZMQ_XPUB_VERBOSE, ZMQ_REQ_CORRELATE, and ZMQ_REQ_RELAXED, only take effect for subsequent socket bind/connects. Specifically, security options take effect for subsequent bind/connect calls, and can be changed at…
zmq_sendmsg – send a message part on a socket Synopsis int zmq_sendmsg(void *socket, zmq_msg_t *msg, int flags); Description The zmq_sendmsg() function shall queue the message referenced by the msg argument to be sent to the socket referenced by the socket argument. The flags argument is a combination of the flags defined below: ZMQ_DONTWAIT For socket…
zmq_send_const – send a constant-memory message part on a socket Synopsis int zmq_send_const(void *socket, void *buf, size_t len, int flags); Description The zmq_send_const() function shall queue a message created from the buffer referenced by the buf and len arguments. The message buffer is assumed to be constant-memory and will therefore not be copied or deallocated…
zmq_send – send a message part on a socket Synopsis int zmq_send(void *socket, void *buf, size_t len, int flags); Description The zmq_send() function shall queue a message created from the buffer referenced by the buf and len arguments. The flags argument is a combination of the flags defined below: ZMQ_DONTWAIT For socket types (DEALER, PUSH)…
zmq_recvmsg – receive a message part from a socket Synopsis int zmq_recvmsg(void *socket, zmq_msg_t *msg, int flags); Description The zmq_recvmsg() function shall receive a message part from the socket referenced by the socket argument and store it in the message referenced by the msg argument. Any content previously stored in msg shall be properly deallocated….
zmq_recv – receive a message part from a socket Synopsis int zmq_recv(void *socket, void *buf, size_t len, int flags); Description The zmq_recv() function shall receive a message from the socket referenced by the socket argument and store it in the buffer referenced by the buf argument. Any bytes exceeding the length specified by the len…
zmq_proxy_steerable – built-in 0MQ proxy with control flow Synopsis int zmq_proxy_steerable(const void *frontend, const void *backend, const void *capture, const void *control); Description The zmq_proxy_steerable() function starts the built-in 0MQ proxy in the current application thread, as zmq_proxy() do. Please, refer to this function for the general description and usage. We describe here only the…
zmq_proxy – start built-in 0MQ proxy Synopsis int zmq_proxy(const void *frontend, const void *backend, const void *capture); Description The zmq_proxy() function starts the built-in 0MQ proxy in the current application thread. The proxy connects a frontend socket to a backend socket. Conceptually, data flows from frontend to backend. Depending on the socket types, replies may…
zmq_poll – input/output multiplexing Synopsis int zmq_poll(zmq_pollitem_t *items, int nitems, long timeout); Description The zmq_poll() function provides a mechanism for applications to multiplex input/output events in a level-triggered fashion over a set of sockets. Each member of the array pointed to by the items argument is a zmq_pollitem_t structure. The nitems argument specifies the number…
zmq_msg_size – retrieve message content size in bytes Synopsis size_t zmq_msg_size (zmq_msg_t *msg); Description The zmq_msg_size() function shall return the size in bytes of the content of the message object referenced by msg. Caution Never access zmq_msg_t members directly, instead always use the zmq_msg family of functions. Return Value Upon successful completion, zmq_msg_size() shall return…
zmq_msg_set – set message property Synopsis int zmq_msg_set(zmq_msg_t *message, int property, int value); Description The zmq_msg_set() function shall set the property specified by the property argument to the value of the value argument for the 0MQ message fragment pointed to by the message argument. Currently the zmq_msg_set() function does not support any property names. Return…
zmq_msg_send – send a message part on a socket Synopsis int zmq_msg_send(zmq_msg_t *msg, void *socket, int flags); Description The zmq_msg_send() function is identical to zmq_sendmsg(3), which shall be deprecated in future versions. zmq_msg_send() is more consistent with other message manipulation functions. The zmq_msg_send() function shall queue the message referenced by the msg argument to be…
zmq_msg_recv – receive a message part from a socket Synopsis int zmq_msg_recv(zmq_msg_t *msg, void *socket, int flags); Description The zmq_msg_recv() function is identical to zmq_recvmsg(3), which shall be deprecated in future versions. zmq_msg_recv() is more consistent with other message manipulation functions. The zmq_msg_recv() function shall receive a message part from the socket referenced by the…
zmq_msg_move – move content of a message to another message Synopsis int zmq_msg_move(zmq_msg_t *dest, zmq_msg_t *src); Description The zmq_msg_move() function shall move the content of the message object referenced by src to the message object referenced by dest. No actual copying of message content is performed, dest is simply updated to reference the new content….
zmq_msg_more – indicate if there are more message parts to receive Synopsis int zmq_msg_more(zmq_msg_t *message); Description The zmq_msg_more() function indicates whether this is part of a multi-part message, and there are further parts to receive. This method can safely be called after zmq_msg_close(). This method is identical to zmq_msg_get() with an argument of ZMQ_MORE. Return…
zmq_msg_init_size – initialise 0MQ message of a specified size Synopsis int zmq_msg_init_size(zmq_msg_t *msg, size_t size); Description The zmq_msg_init_size() function shall allocate any resources required to store a message size bytes long and initialise the message object referenced by msg to represent the newly allocated message. The implementation shall choose whether to store message content on…