进行文件传输，可以控制发送端和接收端的传输文件内容（由用户自主填充）、时间、大小、以及传输协议的选择。并且可以记录文件的相关信息并返回出错提示(File transfer, you can control the sending and receiving side of the transmission, file content (by the user self filling), time, size, and the choice of transmission protocol. A