read.c

#include <string.h>
#include <stdio.h>
#include <zmq.h>
#include <assert.h>


int main (int argc, char ** archv) {
        void * context = zmq_init(1);
        void *socket = zmq_socket (context, ZMQ_SUB);
        assert (socket);
        int rc = zmq_connect (socket, "tcp://0.0.0.0:8080"); assert (rc == 0);

        char buf[2];
        while (1) {
                memset(buf, 0, 2);
                printf("receiving\n");
                zmq_recv(socket, buf, 1, 0);

                printf("%s\n", buf);
        }
}

# cc -lzmq reader.c -o reader && ./reader
# receiving
# … blocks forever