mkdir命令是常用的命令，用来建立空目录，它还有2个常用参数：

• -m, --mode=模式 设定权限 (类似 chmod)，而不是 rwxrwxrwx 减 umask
• -p, --parents 需要时创建上层目录，如目录早已存在则不当作错误

下面是英文原版

-m, --mode=MODE set file mode (as in chmod), not a=rwx - umask

-p, --parents no error if existing, make parent directories as needed

-v, --verbose print a message for each created directory

-Z set SELinux security context of each created directory

to the default type

--context[=CTX] like -Z, or if CTX is specified then set the SELinux

or SMACK security context to CTX

--help display this help and exit

--version output version information and exit