client创建udp原始套接字，将数据存入buf中，进行网络的捕包，从中过滤识别出80端口的包，打印出五元组的信息。server端开启守护进程，接受前端发送的信息，并将其保存到文件中。-create udp raw socket client, the data stored in buf, make the network packet capture, filter identified 80 ports from which the package, print out the five

类似于qq的聊天工具，采用socket编程，用于了多线程，select，还有心跳机制，守护进程！-Similar to qq chat tool, using socket programming for a multi-threaded, select, and heartbeat mechanism, the daemon!

User-space proxy arp daemon, hand for small networks and training.