GCC编译器问题

Question

我是一个学习Linux的小白，按照教程敲的代码，但是执行之后的结果却很诡异，不知道怎么回事，希望大佬们可以帮忙看一下
我先贴出自己的程序：
#include <pthread.h>
#include <stdio.h>
#include <unistd.h>
#include <stdlib.h>
#include <string.h>
#include <signal.h>
#include <errno.h>
#include <limits.h>
#include <syspes.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <sysan.h>
 
pthread_mutex_t mutex=PTHREAD_MUTEX_INITIALIZER;
 
void prepare()
{
        pthread_mutex_lock(&mutex);
        printf("I am prepare\n");
}
void parent()
{
        pthread_mutex_unlock(&mutex);
        printf("I am parent\n");
}
void child()
{
        pthread_mutex_unlock(&mutex);
        printf("I am child\n");
}
void *thread_fun(void *arg)
{
        sleep(1);
        pid_t pid;
        pthread_atfork(prepare,parent,child);
        pid=fork();
        if(pid == 0)
        {
                pthread_mutex_lock(&mutex);
                printf("child process\n");
                pthread_mutex_unlock(&mutex);
        }
        if(pid > 0)
        {
                pthread_mutex_lock(&mutex);
                printf("parent process\n");
                pthread_mutex_unlock(&mutex);
        }
}
 
int main()
{
        pthread_t tid;
        if(pthread_create(&tid,NULL,thread_fun,NULL))
        {
                printf("create new thread failure\n");
                return ;
        }
 
        pthread_mutex_lock(&mutex);
        sleep(1);
        printf("main process\n");
        pthread_mutex_unlock(&mutex);
        pthread_join(tid,NULL);
 
        pthread_mutex_destroy(&mutex);
        return 0;
}
然后我的执行结果却是这样的

Answer 1

你的意思是不是I am child 和 child process的输出位置很奇怪

Answer 2

我也遇到过这样的情况，还没有解决。就是他的输出位置不对应该是：
main process
I am prepare
I am parent
parent process
I am child
child process
root@xiaoyi..........
但是结果却是上面的那种情况，不知道为什么？

Answer 3

事实wait
void *thread_fun(void *arg)
{
        int status = 0;
        sleep(1);
        pid_t pid;
        pthread_atfork(prepare,parent,child);
        pid=fork();
        if(pid == 0)
        {
                pthread_mutex_lock(&mutex);
                printf("child process\n");
                pthread_mutex_unlock(&mutex);
        }
        if(pid > 0)
        {
                pthread_mutex_lock(&mutex);
                printf("parent process\n");
                pthread_mutex_unlock(&mutex);
                wait(&status);
        }
}

Answer 4

试试wait
void *thread_fun(void *arg)
{
        int status = 0;
        sleep(1);
        pid_t pid;
        pthread_atfork(prepare,parent,child);
        pid=fork();
        if(pid == 0)
        {
                pthread_mutex_lock(&mutex);
                printf("child process\n");
                pthread_mutex_unlock(&mutex);
        }
        if(pid > 0)
        {
                pthread_mutex_lock(&mutex);
                printf("parent process\n");
                pthread_mutex_unlock(&mutex);
                wait(&status);
        }
}