Linux Common commands-rights management commands

Rights Management Command: chmod

Command name: chmod

Command English Original: Change the permissions mode of a file

Command path:/bin/chmod

Execute Permissions: All Users

Syntax: chmod [{ugoa}{+-=}{rwx}] [file or directory]

[mode=421] [File or directory]

-R Recursive modification

Function Description: Change file or directory permissions

Note

1.U: Owner (user); G: Group; O: Other person (other); +: Increase permissions;-: reduce permissions; =: permission is; r: readable; w: writable; x: executable;

2. Digital representation of permissions

R = 4; W = 2; x = 1 rwxrw-r--= 764; r-x-wx-w-=532;

　　　　

　　　　What the rwx of files and directories mean

File: r:cat/more/head/tail/less

W:vi

X:script command

Directory: R:ls

W:touch/mkdir/rmdir/rm

X:cd

Example: chmod g+w,o-r japanlovestory.list

chmod g=rwx Japanlovestory.list

chmod 640 Japanlovestory.list

Chmod-r 777/tmp/a (recursively modifies the permissions of all directory files under the A directory)

Other Rights Management commands

Command name: Chown

Command English Original: Change file ownership

Command path:/bin/chown

Execute Permissions: All Users

Syntax: chown [user] [file or directory]

Function Description: Change the owner of the file or directory (only root has this permission)

Command name: CHGRP

Command English Original: Change file group ownership

Command path:/BIN/CHGRP

Execute Permissions: All Users
Syntax: chgrp [user Group] [file or directory]

Function Description: Change the file or directory belongs to group example: Chgrp liming Fengjie

Command name: umask

Command English original: the User file-creation mask

Command path: Shell built-in command

Execute Permissions: All Users

Syntax: umask [-S]-s to display new file default permissions rwx

Function Description: Display, set default permissions for files

Example: Umask-s (view default permissions for user-created directories, create a file that does not have umask Execute permissions by default)

Umask 0022 (Show user's permission mask) 022 = 777-755 755 for actual permissions

Umask 022 (set user's permission mask)

Linux Common commands-rights management commands