若干个生产者和消费者共同存取有限大小的缓冲区。存取规则如下：1.生产 者或消费者每个时刻只能有1 个进程生产或消费1 个产品；2.不能向满缓冲 区放产品；不能向空缓冲区取产品。-A number of producers and consumers to access the common buffer of limited size. Access rules as follows: 1. Producers or consumers each time there can be on