#define _POSIX_C_SOURCE 200112L
#include "stdio.h"
#include "unistd.h"
#include "pthread.h"
#include "string.h"

#include "time.h"

//定义且初始化互斥量
pthread_mutex_t mutex = PTHREAD_MUTEX_INITIALIZER;

//线程1
void* task1(void* p)
{
	char str[100];
	pthread_mutex_lock(&mutex);//获取互斥量
	while (1)
	{
		scanf("%s", str);
		if (!strcmp(str, "end"))//等待输入接收到end字符串
		{
			pthread_mutex_unlock(&mutex);//释放互斥量
			return NULL;//结束
		}
	}
	
	return 0;
}


int main()
{
	pthread_t thread;
	pthread_create(&thread, NULL, task1, NULL);
	sleep(1);//等待线程先获取互斥量

	struct timespec wait;
	clock_gettime(CLOCK_REALTIME, &wait);
	wait.tv_sec += 5;//等待到5秒后
	if (!pthread_mutex_timedlock(&mutex, &wait))//获取信号量，等待子线程结束，被阻塞的信号释放
	{
		fputs("end ok\n", stdout);
	}
	else
	{
		fputs("timeout\n", stdout);
	}

	
	return 0;
}

mutex做全局变量，不需要函数初始化，初始化等于PTHREAD_MUTEX_INITIALIZER即可

 thread_mutex_unlock(&mutex) 释放互斥量

pthread_mutex_lock(&mutex) 获取互斥量，未获得则一直阻塞

pthread_mutex_timedlock(&mutex) //扩展：阻塞一段时间无法获取则不再阻塞，返回超时

pthread_mutex_trylock() 尝试获取互斥量，无法获取不阻塞立刻返回