线程函数pthread_join

#include <stdio.h>
#include <stdlib.h>
#include <pthread.h>

void *thrd_func1(void *arg);
void *thrd_func2(void *arg);

int main()
{
    pthread_t tid1,tid2;
    void *tret;
 
    if (pthread_create(&tid1,NULL,thrd_func1,NULL)!=0) {
        printf("Create thread 1 error!\n");
        exit(1);
    }

    if (pthread_create(&tid2,NULL,thrd_func2,NULL)!=0) {
        printf("Create thread 2 error!\n");
        exit(1);
    }
   
    if (pthread_join(tid1,&tret)!=0){
        printf("Join thread 1 error!\n");
        exit(1);
    }
    printf("Thread 1 exit code: %d.\n",(int *)tret);

    if (pthread_join(tid2,&tret)!=0){
        printf("Join thread 2 error!\n");
        exit(1);
    }
    printf("Thread 2 exit code: %d.\n",(int *)tret);
    return 0;
}

void *thrd_func1(void *arg)
{
    printf("Thread 1 returning!\n");
    sleep(3);
    return ((void *)1); // 自动退出线程
}

void *thrd_func2(void *arg){
    printf("Thread 2 returning!\n");
    sleep(8);
    pthread_exit((void *)2);  // 线程主动退出，
}