flux_send(3)

SYNOPSIS

#include <flux/core.h>

int flux_send (flux_t *h, const flux_msg_t *msg, int flags);

int flux_send_new (flux_t *h, flux_msg_t **msg, int flags);

Link with -lflux-core.

DESCRIPTION

flux_send() sends msg using the Flux Message broker, previously opened with flux_open(3) on handle h.

flags is the logical "or" of zero or more of the following flags:

FLUX_O_TRACE: Dumps msg to stderr.
FLUX_O_NONBLOCK: If unable to send, return an error rather than block.

Internally, flags are the logical "or" of flags and the flags provided to flux_open(3) when the handle was created.

The message type, topic string, and nodeid affect how the message will be routed by the broker. These attributes are pre-set in the message.

flux_send_new() is the same, except message ownership is transferred to the handle h. The double pointer msg points to a NULL value if the message is successfully transferred. The send fails if the message reference count is greater than one.

RETURN VALUE

flux_send() returns zero on success. On error, -1 is returned, and errno is set appropriately.

ERRORS

ENOSYS: Handle has no send operation.
EINVAL: Some arguments were invalid.
EAGAIN: FLUX_O_NONBLOCK was selected and flux_send() would block.

EXAMPLES

This example opens the Flux broker and publishes an event message.

#include <flux/core.h>
#include "die.h"

int main (int argc, char **argv)
{
    flux_t *h;
    flux_msg_t *msg;

    if (!(h = flux_open (NULL, 0)))
        die ("flux open %s", "NULL");
    if (!(msg = flux_event_encode ("snack.bar.closing", NULL)))
        die ("flux_event_encode");
    if (flux_send (h, msg, 0) < 0)
        die ("flux_send");
    flux_msg_destroy (msg);
    flux_close (h);
    return (0);
}