linux 互斥锁应用实例(2)

if (work_area[0] != '\0') //检查读入的内容输出没有

{

pthread_mutex_unlock(&work_mutex); //unlock the mutex如果没有输出，解锁

sleep(1);

}

else

{

break;

}

}

}

pthread_mutex_unlock(&work_mutex);//解锁

printf("\nWaiting for thread to finish...\n");

res = pthread_join(a_thread, &thread_result);//等待另一个线程结束

if (res != 0)

{

perror("Thread join failed");

exit(EXIT_FAILURE);

}

printf("Thread joined\n");

pthread_mutex_destroy(&work_mutex);//销毁互斥锁

exit(EXIT_SUCCESS);

}

void *thread_function(void *arg)

{

sleep(1);

pthread_mutex_lock(&work_mutex);//上锁，抢占资源

while(strncmp("end", work_area, 3) != 0) //判断是不是结束信息end

{

printf("You input %d characters\n", strlen(work_area) -1);//时结束信心的话，就输出输入的字符个数

printf("the characters is %s",work_area);//输出输入的字符内容

work_area[0] = '\0';//设置最后以为为“\0”

pthread_mutex_unlock(&work_mutex);// 输出完成以后就解锁

sleep(1);

pthread_mutex_lock(&work_mutex);//上锁

while (work_area[0] == '\0' ) //判断第一位是不是为\0

{

pthread_mutex_unlock(&work_mutex);//解锁等待

sleep(1);

pthread_mutex_lock(&work_mutex);//上锁再次循环

}