DragonFly On-Line Manual Pages

NN_SEND(3)                      nanomsg manual                      NN_SEND(3)

NAME
       nn_send - send a message

SYNOPSIS
       #include <nanomsg/nn.h>

       int nn_send (int s, const void *buf, size_t len, int flags);

DESCRIPTION
       The function will send a message containing the data from buffer
       pointed to by buf parameter to the socket s. The message will be len
       bytes long.

       Alternatively, to send a buffer allocated by nn_allocmsg(3) function
       set the buf parameter to point to the pointer to the buffer and len
       parameter to NN_MSG constant. In this case a successful call to nn_send
       will deallocate the buffer. Trying to deallocate it afterwards will
       result in undefined behaviour.

       Which of the peers the message will be sent to is determined by the
       particular socket type.

       The flags argument is a combination of the flags defined below:

       NN_DONTWAIT
           Specifies that the operation should be performed in non-blocking
           mode. If the message cannot be sent straight away, the function
           will fail with errno set to EAGAIN.

RETURN VALUE
       If the function succeeds, the number of bytes in the message is
       returned. Otherwise, -1 is returned and errno is set to to one of the
       values defined below.

ERRORS
       EFAULT

           buf is NULL or len is NN_MSG and the message pointer (pointed to by
           buf) is NULL.

       EBADF
           The provided socket is invalid.

       ENOTSUP
           The operation is not supported by this socket type.

       EFSM
           The operation cannot be performed on this socket at the moment
           because the socket is not in the appropriate state. This error may
           occur with socket types that switch between several states.

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

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

       ETIMEDOUT
           Individual socket types may define their own specific timeouts. If
           such timeout is hit, this error will be returned.

       ETERM
           The library is terminating.

EXAMPLE
       Using data directly:

           nbytes = nn_send (s, "ABC", 3, 0);
           assert (nbytes == 3);

       Using a pre-allocated message buffer:

           void *msg = nn_allocmsg(3, 0);
           strncpy(msg, "ABC", 3);
           nbytes = nn_send (s, &msg, NN_MSG, 0);
           assert (nbytes == 3);

SEE ALSO
       nn_recv(3) nn_sendmsg(3) nn_socket(3) nanomsg(7)

AUTHORS
       Martin Sustrik <sustrik@250bpm.com[1]>

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

nanomsg Unknown                   12/23/2015                        NN_SEND(3)