三个同步与互斥问题之生产者与消费者

#include<stdio.h>

#include<pthread.h>

pthread_mutex_t mutex;

#define Max 10

pthread_cond_t pro;

pthread_cond_t con;

int buffer=0;//全局变量----一开始为0，只有生产者可以执行

void deal_produce(void *arg)

{//消费---

int i;

for(i=1;i<=Max;i++)

{//

pthread_mutex_lock(&mutex);

while(buffer!=0) pthread_cond_wait(&pro,&mutex);//锁住生产者,在有产品的时候

printf("producer produce item :%d\n",i);

buffer=i;

pthread_cond_signal(&con);//通知消费者

pthread_mutex_unlock(&mutex);

}

pthread_exit(NULL);

}

void deal_consume(void *arg)

{//生产

int i;

for(i=1;i<=Max;i++)

{//加锁，消费的时候不准生产

pthread_mutex_lock(&mutex);

while(buffer==0) pthread_cond_wait(&con,&mutex);

printf("consumer consume item :%d\n",i);

buffer=0;//！？buffer--?

if(buffer==0) pthread_cond_signal(&pro);//没货待产

pthread_mutex_unlock(&mutex);

}

pthread_exit(NULL);

}

int main()

{

pthread_t consumer,producer;

pthread_mutex_init(&mutex,0);

//0 :NULL

//API :int pthread_mutex_init(pthread_mutex_t *mutex, const pthread_mutexattr_t *mutexattr)

pthread_cond_init(&pro,0);

pthread_cond_init(&con,0);

pthread_create(&producer,NULL,&deal_produce,NULL);

pthread_create(&consumer,NULL,&deal_consume,NULL);

pthread_join(consumer);

pthread_join(producer);

pthread_cond_destroy(&pro);

pthread_cond_destroy(&con);

exit(0);

}