Yunduan CUI graphical user interfaces make easy tasks easy, while command line interfaces make difficult tasks possible Part 1 学习Shell 1. 什么是 Shell? Shell 是用户与操作系统交流的程序,它读取用户的键盘输入并交由操作系统执行相应的命令.所有linux都支持一个叫做 bash 的shell,它的全称是 "Bourne Again SHell&quo…