[root@system1 11]# ls [0-9][0-9]
33
[root@system1 11]# ls [a-Z][a-Z]
ls: cannot access [a-Z][a-Z]: No such file or directory
[root@system1 11]# ls [1,2,3][,3,4,5]
ls: cannot access [1,2,3][,3,4,5]: No such file or directory
[root@system1 11]# ls [1,2,3][,3]
ls: cannot access [1,2,3][,3]: No such file or directory
[root@system1 11]# ls [1,2,3][3]
ls: cannot access [1,2,3][3]: No such file or directory
[root@system1 11]# ls [3][3]
ls: cannot access [3][3]: No such file or directory
[root@system1 11]# ls
22
[root@system1 11]# pwd
/root/11
[root@system1 11]#
原文：https://www.cnblogs.com/passwd/p/12182042.html