broken_stream_server.c

#include <czmq.h>

int main(void) {
  zsock_t *server = zsock_new_stream ("@tcp://*:8080");
  assert (server);

  while (!zsys_interrupted) {
    zmsg_t *msg = zmsg_recv (server);
    if (!msg)
      break;
    zmsg_print (msg);
    zmsg_destroy (&msg);
  }
  
  return 0;
}

This is normal, STREAM sends a null frame on a new client connection. This is actually an API break over 4.0. We should have made it a socket option, and that is still a possibility before 4.1.x stable.

Would be a good option to have, so you can initialize objects.