Reproduce ZMQ_LINGER problem

gistfile1.txt

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


int main(int argc, char *argv[]) {
    void *ctx, *socket;
    int rc, pid;
    int msgsize = 0;

    sscanf(argv[1], "%d", &msgsize);

    if ((pid = fork()) == 0) {
        printf("Sender pid: %d\n", getpid());
        ctx = zmq_ctx_new();

        char *buf;
        buf = malloc(msgsize);
        memset (buf, 'A', msgsize);

        socket = zmq_socket (ctx, ZMQ_PUSH);
        zmq_connect(socket, "tcp://127.0.0.1:12345");
        rc = zmq_send (socket, buf, msgsize, 0);
        printf("Sent message of %d bytes\n", rc);
        zmq_close (socket);
        zmq_term (ctx);
        free(buf);
        printf("Sender exiting\n");
    } else {
        char *buf;
        int nbytes;
        printf("Receiver pid: %d\n", getpid());

        buf = malloc(msgsize);
        ctx = zmq_ctx_new();
        socket = zmq_socket (ctx, ZMQ_PULL);
        zmq_bind(socket, "tcp://127.0.0.1:12345");
        nbytes = zmq_recv (socket, buf, msgsize, 0);
        printf("Received msg of %d bytes\n", nbytes);
        zmq_close (socket);
        zmq_term (ctx);
        free(buf);
        printf("Receiver exiting\n");
    }

    return 0;
}