Windows下编写基于消息的网络应用程序，掌握阻塞与非阻塞网络程序的编写，理解在Windows平台下，采用异步选择机制可以提高网络应用程序的性能。-Under Windows-based news network to prepare applications, obstructive and non-blocking network to master the preparation of procedures, understanding the Windows platform, usi