pthread 实现生产者消费者问题

经典的生产者消费者问题，在这里用信号量和互斥量来实现生产和消费者模型

#include<cstdlib>
#include<cstdio>
#include<unistd.h>
#include<pthread.h>
#include<semaphore.h>
int t = 0;
sem_t empty,full;
pthread_mutex_t mutex;
void*  producer(void* arg){
    int* time=(int*) arg;
    while(true){
        sem_wait(&empty);
        pthread_mutex_lock(&mutex);
        //add
        t++;
        printf("producer add 1 to %d\n", t);
        pthread_mutex_unlock(&mutex);
        sem_post(&full);
        sleep(*time);
    }
}

void* customer(void* arg){

    while(true){
        sem_wait(&full);
        pthread_mutex_lock(&mutex);
        //delete
        t--;
        printf("customer delete 1 to %d\n", t);
        pthread_mutex_unlock(&mutex);
        sem_post(&empty);
        sleep(4);
    }
}

int main(){
    pthread_t pthread_producer,pthread_producer_2;
    pthread_t pthread_customer;
    pthread_mutex_init(&mutex,NULL);
    sem_init(&full,0,0);
    sem_init(&empty,0,10);
    int a = 2;
    int b = 3;
    pthread_create(&pthread_producer,NULL,producer,&a);
    pthread_create(&pthread_producer_2,NULL,producer,&b);
    pthread_create(&pthread_customer,NULL,customer,NULL);
    pthread_join(pthread_customer,NULL);
    pthread_join(pthread_producer,NULL);
    pthread_join(pthread_producer_2,NULL);
    return 0;
}