改变文件或者目录的权限
-R 递归式处理
[ugoa][+-=][rwxXst] || [1234567]{3}
X execute/search only if the file is a directory or already has execute permission for some user s 授予文件以文件所有者/组的权限 t 限制删除和粘滞特性
改变文件属性:
chmod u+w /path/to/file