"Linux" File hidden properties

Chattr setting hidden properties of a file

#chattr [+-=] [asacdistu] File or directory

Parameters:

+: Add a special parameter, other existing parameters will not move

-: Delete A special parameter, other existing parameters will not move

=: only the following parameters

A: When a is set, the access time of this file (or directory) Atime will not be modified. You can avoid over-accessing disks for slow I/O machines.

S: General files are written to disk in an asynchronous format, and if you add s this property, any modifications to the file will be "synchronized" to the disk.

A: After setting a, this file will only add data, not delete or modify the data, only root can set this property.

C: After this property is set, it will automatically compress the file, when it is read, it will be automatically decompressed, but when it is stored, it will be compressed and then stored.

D: When the dump program is executed, setting the D property will cause the file (or directory) to not be backed up by dump.

I: It can make a file cannot be deleted, renamed, set the connection and cannot write or add data. Only root can set this property.

S: When the file is set to the S property, if the file is deleted, it will be completely deleted from this hard disk space.

U: In contrast to S, when you use U to configure a file, if the file is deleted, the data content actually exists on the disk.

Lsattr Show file Hidden properties

#lsattr [-adr] File or directory

Parameters:

-A: Show hidden properties as well

-D: If a directory is followed, only the properties of the directory itself, not the file name within the directory

-r: Data along with subdirectories are also listed

"Linux" File hidden properties