1. View the time of the file

There are three types of file times:

Last access time (Access): After viewing the file with cat, less, etc., the time changes

Last change time (Modify): After vim modifies the content of the file, all three times are changed

Last change time (Change): After chmod modifies the file permissions or attributes, the time changes

• stat command to view the status of files

 stat 3. log //查看某个文件的状态stat * //查看这个目录下所有文件及文件夹的状态（不递归）

• ll –time command (without –time, the default is mtime)

 ll --time = atime //查看访问时间ll --time = ctime