gistfile1.txt

#include <stdint.h>
#include <unistd.h>
#include <zmq.hpp>

int main ()
{
    zmq::context_t ctx (1);

    zmq::socket_t s (ctx, ZMQ_XREP);
    const int64_t hwm = 1;
    s.setsockopt (ZMQ_HWM, &hwm, sizeof (hwm));
    s.bind ("tcp://127.0.0.1:23001");

    zmq::socket_t s2 (ctx, ZMQ_XREQ);
    s2.setsockopt (ZMQ_IDENTITY, "A", 1);
    s2.connect ("tcp://127.0.0.1:23001");

    sleep (1);

    for (int i = 0; i < 2 ; ++i)
    {
        zmq::message_t route (1);
        *(char*) route.data () = 'A';
        s.send (route, ZMQ_SNDMORE);
        zmq::message_t nothing;
        s.send (nothing);
    }
}