 <p>zmq_send and zmq_recv seems to handle zmq_msg_t structures rather than just the buffer.<p> Maybe you should try to create such structures rather than just sending your buffer ?<p> See the examples in <a href="http://api.zeromq.org/2-1:zmq-send" rel="nofollow">http://api.zeromq.org/2-1:zmq-send</a> and <a href="http://api.zeromq.org/2-1:zmq-recv" rel="nofollow">http://api.zeromq.org/2-1:zmq-recv</a></p>