linux ptheard 生产者消费者

 1 #include <stdio.h>
 2 #include <stdlib.h>
 3 #include <pthread.h>
 4 
 5 pthread_mutex_t mutex;
 6 pthread_cond_t cond_full;
 7 pthread_cond_t cond_empty;
 8 
 9 int g_iBufSize = ;
 
 void *thread_producer(void* arg)
 {
     while(true)
     {
         printf("thread_producer:pthread_mutex_lock\n");
         pthread_mutex_lock(&mutex);
         // 拿到lock就可以访问，不会冲突，但是不一定满足条件，cond是为了在满足条件的时候通知另一个进程
         if( != g_iBufSize) //如果条件不满足就调用wait函数等待条件满足
         {
             printf("thread_producer：pthread_cond_wait cond_empty \n");
             pthread_cond_wait(&cond_empty, &mutex); // 这句话的前提是先有锁，这时候会自动先解锁，等到时机来临在加锁
         }
         
         //前面的wait操作已经包含了枷锁，这里直接访问
         printf("thread_producer>>>>>\n");
         g_iBufSize = ;
         
         printf("thread_producer: pthread_cond_signal\n");
         pthread_cond_signal(&cond_full);
    
         pthread_mutex_unlock(&mutex);
     }
     return NULL;
 }
 
 void *thread_consumer(void* arg)
 {
     while(true)
     {
         printf("thread_consumer:pthread_mutex_lock\n");
         pthread_mutex_lock(&mutex);
         if( == g_iBufSize)
         {
             printf("thread_consumer: pthread_cond_wait\n");
             pthread_cond_wait(&cond_full, &mutex);
         }
         
         printf("thread_consumer>>>\n");
         g_iBufSize = ;
         
         printf("thread_consumer: pthread_cond_signal\n");
         pthread_cond_signal(&cond_empty);
         
         pthread_mutex_unlock(&mutex);
 
     }
     return NULL;
 }
 
 //g++ -o bin1 -lpthread mutithread.cpp
 
 int main()
 {
     void *retval1, *retval2;
     pthread_t thread_id_1, thread_id_2;
     
     pthread_mutex_init(&mutex, NULL);
     pthread_cond_init(&cond_full, NULL);
     pthread_cond_init(&cond_empty, NULL);
     
     pthread_cond_signal(&cond_empty);
     pthread_create(&thread_id_1, NULL, thread_producer, NULL);//int pthread_create(pthread_t *tidp, const pthread_attr_t *attr, (void*)(*start_rtn)(void*),void *arg);
     pthread_create(&thread_id_2, NULL, thread_consumer, NULL);
      
     pthread_join(thread_id_1, &retval1); // 阻塞等线程执行完
     pthread_join(thread_id_2, &retval2);
     
     pthread_cond_destroy(&cond_full);
     pthread_cond_destroy(&cond_empty);
     pthread_mutex_destroy(&mutex);
     
     return ;
 }