c - zmq_socket() 给出段错误

Question

我正在学习zeromq，有如下测试代码:

void *context = (void *)zmq_ctx_new();

if (context == NULL) {
    printf("context is null\n");
} else {
    printf("context was created successfully\n");
}

printf("connecting to the 0mq server\n");
void *responder = zmq_socket (context, ZMQ_REQ);

printf("got socket\n");

if (responder == NULL) {
   printf("responder is null\n");
} else {
   printf("responder was created successfully\n");
}

当我运行代码时，它会在调用 zmq_socket() 时崩溃。这是输出:

Starting 0mq server context was created successfully connecting to the 0mq server Segmentation fault (core dumped)

我不确定为什么 zmq_socket() 会失败。我试图在我的 Makefile 中的链接系列的开头移动 zmq 库。它仍然失败。

如有任何帮助，我们将不胜感激。

Answer 1

改变

void context = (void)zmq_ctx_new();

进入

void *context = (void *)zmq_ctx_new();

而且，当我尝试你的代码时，void context = (void) zmq_ctx_new() 会导致编译错误。

这是我的代码，可以在我的 OSX 上运行。

gcc -o cli client.c -lzmq
gcc -o srv server.c -lzmq

客户端.c:

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

int main (void)
{
    printf ("Connecting to hello world server…\n");
    void *context = (void *)zmq_ctx_new ();
    void *requester = zmq_socket (context, ZMQ_REQ);
    zmq_connect (requester, "tcp://localhost:5555");

    int request_nbr;
    for (request_nbr = 0; request_nbr != 10; request_nbr++) {
        char buffer [10];
        char snd[] = "hello";
        printf ("Sending Hello %d…\n", request_nbr);
        zmq_send (requester, snd, sizeof(snd), 0);
        zmq_recv (requester, buffer, 10, 0);
        printf ("Received World %d\n", request_nbr);
    }
    zmq_close (requester);
    zmq_ctx_destroy (context);
    return 0;
}

服务器.c:

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

int main (void)
{   
    //  Socket to talk to clients
    void *context = zmq_ctx_new (); 
    void *responder = zmq_socket (context, ZMQ_REP);
    int rc = zmq_bind (responder, "tcp://*:5555");
    assert (rc == 0); 

    while (1) {
        int  nrecv;
        char buffer [10];
        nrecv = zmq_recv (responder, buffer, 10, 0); 
        printf ("[%d] Received %s\n", nrecv, buffer);
        sleep (1);          //  Do some 'work'
        zmq_send (responder, "World", 5, 0); 
    }   
    return 0;
}