DOKK / manpages / debian 12 / libzmq3-dev / zmq_msg_routing_id.3.en
ZMQ_MSG_ROUTING_ID(3) 0MQ Manual ZMQ_MSG_ROUTING_ID(3)

zmq_msg_routing_id - return routing ID for message, if any

uint32_t zmq_msg_routing_id (zmq_msg_t *message);

The zmq_msg_routing_id() function returns the routing ID for the message, if any. The routing ID is set on all messages received from a ZMQ_SERVER socket. To send a message to a ZMQ_SERVER socket you must set the routing ID of a connected ZMQ_CLIENT peer. Routing IDs are transient.

The zmq_msg_routing_id() function shall return zero if there is no routing ID, otherwise it shall return an unsigned 32-bit integer greater than zero.

Receiving a client message and routing ID.

void *ctx = zmq_ctx_new ();
assert (ctx);
void *server = zmq_socket (ctx, ZMQ_SERVER);
assert (server);
int rc = zmq_bind (server, "tcp://127.0.0.1:8080");
assert (rc == 0);
zmq_msg_t message;
rc = zmq_msg_init (&message);
assert (rc == 0);
//  Receive a message from socket
rc = zmq_msg_recv (server, &message, 0);
assert (rc != -1);
uint32_t routing_id = zmq_msg_routing_id (&message);
assert (routing_id);

zmq_msg_set_routing_id(3)

This page was written by the 0MQ community. To make a change please read the 0MQ Contribution Policy at http://www.zeromq.org/docs:contributing.

01/18/2023 0MQ 4.3.4