C语言互斥锁-条件变量实现公共缓存区数据读写

#include 
#include 
#include 
#include 
#include 
#include 
#include 
#include 

char buffer[128]; 
int has_data=0;
pthread_mutex_t mutex;
pthread_cond_t cond;
pthread_cond_t cond2;

void read_buf(void)
{
	do
	{
		pthread_mutex_lock(&mutex);//锁定互斥锁
		if(has_data==0)
		{
			/*阻塞线程,等待另外一个线程发送信号，同时为公共数据区解锁*/
			pthread_cond_wait(&cond,&mutex);
		}
		else if(has_data==1)
		{
			printf("the data : %s\n",buffer);
			has_data=0;
			pthread_cond_signal(&cond2);
		}
		pthread_mutex_unlock(&mutex);//打开互斥锁
	}while(strcmp(buffer,"#")!=0);
	pthread_exit(NULL);
}

void write_buf(void)
{
	char input[128];
	do
	{
		pthread_mutex_lock(&mutex);
		if(has_data==0)
		{
			memset(input,'\0',128);
			printf("input data:\t");
			scanf("%s",input);
			sprintf(buffer,"%s",input);
			has_data=1;
			pthread_cond_signal(&cond);//条件改变，唤醒阻塞的线程
		
		}
		else if(has_data==1)
		{
			pthread_cond_wait(&cond2,&mutex);
		}
		pthread_mutex_unlock(&mutex);
	}while(strcmp(input,"#")!=0);
	pthread_exit(NULL);
}
int main(int argc,char **argv)
{
	pthread_t id,id2;
	pthread_cond_init(&cond,NULL);
	pthread_cond_init(&cond2,NULL);
	pthread_mutex_init(&mutex,NULL);
	pthread_create(&id,NULL,(void *)read_buf,NULL);//返回值为0，创建成功
	pthread_create(&id2,NULL,(void *)write_buf,NULL);
	pthread_join(id,NULL);
	pthread_join(id2,NULL);
	pthread_mutex_destroy(&mutex);
	pthread_cond_destroy(&cond);
	return 0;
}