创建一个控制进程，此进程包含n个线程。用这n个线程来表示n个读者或写者。每个线程按相应测试数据文件的要求进行读写操作。用信号量机制分别实现读者优先和写者优先问题。运行结果显示要求：要求在每个线程创建、发出读写申请、开始读写操作和结束读写操作时分别显示一行提示信息，以确定所有处理都遵守相应的读写操作限制。

读者-写者问题的读写操作限制-Create a control process, this process contains n threads. Use of these n threads to represent n-reader or writer. Each thread according to the requirements of the corresponding test data file read and write operations. Semaphore mechanism are used to achieve the reader and the writer first priority. Running results show requirements: requires each thread to create, send the application to read and write and began to read and write operations and the end of the read and write operations showed the line of tips to make sure that all deal with the corresponding read and write operations are to comply with restrictions. Readers- read and write operations to write the problem of limited