说明：  1.客户机能得到从服务器发的IP地址. 2.服务器能根据客户机请求发送适当文件. 3.客户机能收到从服务器发过来的文件. 4.程序采用模块化设计方法,根据TCP/IP的层次结构编写而成.
(1. Guest function been issued from the server IP address. 2. Server based on client request to send the appropriate document. 3. Guest function received from the server sent the file. 4. Procedures modular design method, in accordance with TCP/IP hierarchy prepared.)