linux进阶43——多线程程序设计(三)：线程等待

函数定义

#include int pthread_join(pthread_t tid, void **rval_ptr);

阻塞调用线程&＃xff0c;直到指定的线程终止。

返回值

成功返回0&＃xff0c;失败返回错误码。

错误码定义如下&＃xff1a;

ERRORSEDEADLKA deadlock was detected (e.g., two threads tried to join with each other); or thread specifies the calling thread.&＃xff08;检测到死锁&＃xff09;EINVAL thread is not a joinable thread.&＃xff08;不是可连接的线程&＃xff09;EINVAL Another thread is already waiting to join with this thread.&＃xff08;另一个线程已经在等待加入这个线程&＃xff09;ESRCH No thread with the ID thread could be found.&＃xff08;找不到对应ID的线程&＃xff09;

参数

tid&＃xff1a;等待退出的线程id

rval_ptr&＃xff1a;线程退出的返回值指针

示例

#include
#include
#include void *myThread(void *str)
{for(int i &＃61; 0; i <5; i&＃43;&＃43;){sleep(2);printf("child thread is : %d\n", i);}return NULL;
}int main()
{pthread_t tid;int ret, i;ret &＃61; pthread_create(&tid, NULL, myThread, NULL);if(ret !&＃61; 0){printf("thread create error!\n");return -1;}ret &＃61; pthread_join(tid, NULL);if(ret !&＃61; 0){printf("thread join error!\n");return -2;}for(i &＃61; 0; i <5; i&＃43;&＃43;){sleep(1);printf("main thread is : %d\n", i);}return 0;
}


编译运行&＃xff1a;

[root&＃64;192 pthread]# gcc -lpthread pthread_join.c -o pthread_join
[root&＃64;192 pthread]# ./pthread_join
child thread is : 0
child thread is : 1
child thread is : 2
child thread is : 3
child thread is : 4
main thread is : 0
main thread is : 1
main thread is : 2
main thread is : 3
main thread is : 4