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#include #include #include void *producter_f(void *arg); void *consumer_f(void *arg); int buffer_has_item = 0; /*设置缓存数量*/ pthread_mutex_t mutex; /*设置互斥*/ int running = 1; int main (void) { pthread_t consumer_t; /*线程参数*/ pthread_t producter_t; /*不知道这句为什么不给我变蓝色，初始化互斥*/ pthread_mutex_init(&mutex, NULL); /*创建线程*/ pthread_create(&producter_t, NULL, (void *)producter_f, NULL); pthread_create(&consumer_t, NULL, (void *)consumer_f, NULL); usleep(1); running = 0; /*等待线程退出，一个线程不能够被多个线程等待*/ pthread_join(consumer_t, NULL); pthread_join(producter_t, NULL); /*销毁互斥*/ pthread_mutex_destroy(&mutex); return 0; } void *producter_f(void *arg) { while (running) { pthread_mutex_lock(&mutex); /*加锁，进入互斥区*/ buffer_has_item++; printf("product ,num:%d\n", buffer_has_item); pthread_mutex_unlock(&mutex); /*解锁，离开互斥区*/ } } void *consumer_f(void *arg) { while (running) { pthread_mutex_lock(&mutex); buffer_has_item--; printf("consumer,num:%d\n",buffer_has_item); pthread_mutex_unlock(&mutex); } } /* *生产者消费者问题的信号量控制，可以与上述程序进行对比，出处--同上 */ #include #include #include void *producter_f(void *arg); void *consumer_f(void *arg); sem_t sem; int running = 1; int main (void) { pthread_t consumer_t; pthread_t producter_t; sem_init(&sem, 0, 16); /*信号量初始化*/ pthread_create(&producter_t, NULL, (void*)producter_f, NULL); pthread_create(&consumer_t, NULL, (void *)consumer_f, NULL); sleep(1); running = 0; pthread_join(consumer_t, NULL); pthread_join(producter_t, NULL); sem_destroy(&sem); /*销毁信号量*/ return 0; } void *producter_f(void *arg) { int semval = 0; /*信号量的初始值*/ while (running) { usleep(1); sem_post(&sem); /*信号量+1*/ sem_getvalue(&sem, &semval);/*得到信号量的值*/ printf("pro,num:%d\n",semval); } } void *consumer_f(void *arg) { int semval = 0; while (running) { usleep(1); sem_wait(&sem); /*信号量-1*/ sem_getvalue(&sem, &semval); printf("con num:%d\n",semval); } } /* *条件变量来控制线程的同步，根据百度百科代码改编而成，不肯定没有错误 */ #include #include #include void decrement_count(void); void increment_count(void); /**/ pthread_mutex_t count_lock; /**/ pthread_cond_t count_nonzero; unsigned count; int main(void) { pthread_t decrement_t; pthread_t increment_t; /*初始化互斥*/ pthread_mutex_init(&count_lock, NULL); pthread_create(&decrement_t, NULL, (void*)&decrement_count, NULL); pthread_create(&increment_t, NULL, (void*)&decrement_count, NULL ); usleep(1); pthread_join(decrement_t, NULL); pthread_join(increment_t, NULL); pthread_mutex_destroy(&count_lock); return 0; } void decrement_count(void) { pthread_mutex_lock(&count_lock); while (count == 0) {/*使线程阻塞在一个条件变量上线程可以被函数pthread_cond_signal函数唤醒*/ pthread_cond_wait(&count_nonzero, &count_lock); } count = count - 1; pthread_mutex_unlock(&count_lock); } void increment_count(void) { pthread_mutex_lock(&count_lock); if (count == 0) {/*它用来释放被阻塞在条件变量cond上的一个线程*/ pthread_cond_signal(&count_nonzero); } count = count + 1; pthread_mutex_unlock(&count_lock); } |
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