pthread_jion() , pthread_create() 导致的segmentation fault

下午调试程序的“segmentation fault”，先上代码：

int main()
{
printf("entering main() /n");
init_globals(); /*initialize global variable defined in main.c*/
init_iic();
init_spi();
if(init_sock() == -1){
exit(1);
}
sock_listen_tid = pthread_create(&sock_listen_tid,NULL,listen_thread,NULL);
if( sock_listen_tid!= 0){
printf("pthread_create()  error /n");
exit(1);
}
//sleep(10);
pthread_join(sock_listen_tid,NULL);
return 0;
}
void* listen_thread(void* arg)
{
//省略
return ((void*)0);
}

左看右看找不到错在那，尝试去掉pthread_join, 竟然正常了。

注意这句：

sock_listen_tid = pthread_create(&sock_listen_tid,NULL,listen_thread,NULL);

pthread_create的返回值赋给了sock_listen_tid，这行代码看起来的确的确的确有些怪~

看函数说明 man 3 pthread_create

函数返回值描述如下：

RETURN VALUE

If successful, the pthread_create() function shall return zero; otherwise,

an error number shall be returned to indicate the error.

ERRORS

The pthread_create() function shall fail if:

EAGAIN The system lacked the necessary resources to create another thread,

or the system-imposed limit on the total number of threads in a

process {PTHREAD_THREADS_MAX} would be exceeded.

EINVAL The value specified by attr is invalid.

EPERM The caller does not have appropriate permission to set the required

scheduling parameters or scheduling policy.

The pthread_create() function shall not return an error code of [EINTR].

The following sections are informative.

如果创建成功, pthread_create将返回0. 赋值给sock_listen_tid等于0。然后执行pthread_join(0, NULL)，相当于等待线程号为0的线程，当然segmentation fault