Provided by: libzmq-dev_2.1.11-1ubuntu1_amd64 bug

NAME

       zmq_send - send a message on a socket

SYNOPSIS

       int zmq_send (void *socket, zmq_msg_t *msg, int flags);

DESCRIPTION

       The zmq_send() 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_NOBLOCK
           Specifies that the operation should be performed in non-blocking mode. If the message
           cannot be queued on the socket, the zmq_send() function shall fail with errno set to
           EAGAIN.

       ZMQ_SNDMORE
           Specifies that the message being sent is a multi-part message, and that further
           message parts are to follow. Refer to the section regarding multi-part messages below
           for a detailed description.

       The zmq_msg_t structure passed to zmq_send() is nullified during the call. If you want to
       send the same message to multiple sockets you have to copy it using (e.g. using
       zmq_msg_copy()).

           Note
           A successful invocation of zmq_send() does not indicate that the message has been
           transmitted to the network, only that it has been queued on the socket and 0MQ has
           assumed responsibility for the message.

   Multi-part messages
       A 0MQ message is composed of 1 or more message parts; each message part is an independent
       zmq_msg_t in its own right. 0MQ ensures atomic delivery of messages; peers shall receive
       either all message parts of a message or none at all.

       The total number of message parts is unlimited.

       An application wishing to send a multi-part message does so by specifying the ZMQ_SNDMORE
       flag to zmq_send(). The presence of this flag indicates to 0MQ that the message being sent
       is a multi-part message and that more message parts are to follow. When the application
       wishes to send the final message part it does so by calling zmq_send() without the
       ZMQ_SNDMORE flag; this indicates that no more message parts are to follow.

RETURN VALUE

       The zmq_send() function shall return zero if successful. Otherwise it shall return -1 and
       set errno to one of the values defined below.

ERRORS

       EAGAIN
           Non-blocking mode was requested and the message cannot be sent at the moment.

       ENOTSUP
           The zmq_send() operation is not supported by this socket type.

       EFSM
           The zmq_send() operation cannot be performed on this socket at the moment due to the
           socket not being in the appropriate state. This error may occur with socket types that
           switch between several states, such as ZMQ_REP. See the messaging patterns section of
           zmq_socket(3) for more information.

       ETERM
           The 0MQ context associated with the specified socket was terminated.

       ENOTSOCK
           The provided socket was invalid.

       EINTR
           The operation was interrupted by delivery of a signal before the message was sent.

       EFAULT
           Invalid message.

EXAMPLE

       Filling in a message and sending it to a socket.

           /* Create a new message, allocating 6 bytes for message content */
           zmq_msg_t msg;
           int rc = zmq_msg_init_size (&msg, 6);
           assert (rc == 0);
           /* Fill in message content with 'AAAAAA' */
           memset (zmq_msg_data (&msg), 'A', 6);
           /* Send the message to the socket */
           rc = zmq_send (socket, &msg, 0);
           assert (rc == 0);

       Sending a multi-part message.

           /* Send a multi-part message consisting of three parts to socket */
           rc = zmq_send (socket, &part1, ZMQ_SNDMORE);
           rc = zmq_send (socket, &part2, ZMQ_SNDMORE);
           /* Final part; no more parts to follow */
           rc = zmq_send (socket, &part3, 0);

SEE ALSO

       zmq_recv(3) zmq_socket(7) zmq(7)

AUTHORS

       This 0MQ manual page was written by Martin Sustrik <sustrik@250bpm.com[1]> and Martin
       Lucina <mato@kotelna.sk[2]>.

NOTES

        1. sustrik@250bpm.com
           mailto:sustrik@250bpm.com

        2. mato@kotelna.sk
           mailto:mato@kotelna.sk