读者—写者问题的读写操作限制(包括读者优先和写者优先)：

1)写—写互斥，即不能有两个写者同时进行写操作。

2)读—写互斥，即不能同时有一个线程在读，而另一个线程在写。

3)读—读允许，即可以有一个或多个读者在读。

-readers-the problem was the restrictions on reading and writing operations (including readers wrote priority and priority) : 1) write-write mutex, and that is not written there were two parallel write. 2) read-write exclusive, and that is not also a thread reading, and writing in another thread. 3) Reading-time permitting, there may be one or more readers in Reading.