C套接字未在Mac OS X上运行

时间:2013-04-16 13:16:16

标签: c macos sockets

以下代码在Ubuntu上运行并与客户端通信而没有任何问题。但是,我需要在Mac OS X上运行。我可以编译它没有错误但是当我尝试运行它时会出现以下消息:"中止陷阱:6" 。我试图谷歌它但无法找到任何有用的信息。即使我在主函数的开头放置了printf,它也不会运行。谢谢你的任何建议。

#include <stdio.h>
#include <sys/socket.h>
#include <sys/un.h>
#include <sys/types.h>
#include <unistd.h>
#include <string.h>
#define UNIX_PATH_MAX 108

int connection_handler(int connection_fd)
{
    int nbytes;
    char buffer[256];

    nbytes = read(connection_fd, buffer, 256);
    buffer[nbytes] = 0;

    printf("MESSAGE FROM CLIENT: %s\n", buffer);
    nbytes = snprintf(buffer, 256, "hello from the server");
    write(connection_fd, buffer, nbytes);

    close(connection_fd);
     return 0;
}

int main(void)
{
    struct sockaddr_un address;
    int socket_fd, connection_fd;
    socklen_t address_length;
    pid_t child;

    socket_fd = socket(PF_UNIX, SOCK_STREAM, 0);

    if(socket_fd < 0)
    {
        printf("socket() failed\n");
        return 1;
    } 

    unlink("./demo_socket");

    /* start with a clean address structure */
    memset(&address, 0, sizeof(struct sockaddr_un));
    address.sun_family = AF_UNIX;
    snprintf(address.sun_path, UNIX_PATH_MAX, "./demo_socket");

    if(bind(socket_fd, (struct sockaddr *) &address, sizeof(struct sockaddr_un)) != 0)
    {
        printf("bind() failed\n");
        return 1;
    }

    if(listen(socket_fd, 5) != 0)
    {
        printf("listen() failed\n");
        return 1;
    }

    while((connection_fd = accept(socket_fd, (struct sockaddr *) &address,&address_length)) > -1)
    {
        child = fork();
        if(child == 0)
        {
            /* now inside newly created connection handling process */
            return connection_handler(connection_fd);
        }
        /* still inside server process */
        close(connection_fd);
    }

    close(socket_fd);
    unlink("./demo_socket");
    return 0;
}

2 个答案:

答案 0 :(得分:4)

您已将UNIX_PATH_MAX硬编码为108,但sun_path中的sockaddr_un仅为104字节:

struct  sockaddr_un {
    unsigned char   sun_len;    /* sockaddr len including null */
    sa_family_t sun_family; /* [XSI] AF_UNIX */
    char        sun_path[104];  /* [XSI] path name (gag) */
};

所以你试图在缓冲区之外写下以下内容:

snprintf(address.sun_path, UNIX_PATH_MAX, "./demo_socket");

您可以使用以下方法解决此问题:

snprintf(address.sun_path, sizeof(address.sun_path), "./demo_socket");

如果您使用了调试器(例如gdb),这将是一个简单的修复。

答案 1 :(得分:0)

可能的原因是您在调用address_length之前未初始化acceptaccept 需要才能在通话前正确初始化。