LinuxPermissions

Permissions matrix

Codes for permissions combinations

• 7 = 4 (r) + 2(w) + 1(x)
• 6 = 4 (r) + 2(w)
• 5 = 4 (r) + 1(x)
• 3 = 2(w) + 1(x)
• 0 - none

Special permissions

Ownership

Setting user and group owner

chown *user_name* *file/dir* - set user owner

chgrp *group_name* *file/dir* - set group owner

Mode

Applying permissions for user owner, group owner, and others

'chmod *SUGO*" - set S-special permission and permissions for U-user G-group, O - others

Default settings

Default settings applies for created files an dirrectories. To find default settings enter umask command, Result shows the numbers substracted from 777 permissions (ex. result of umask 027 means default permission 750)

To change default permissions temporarily enter umask XYZ' with XYZ as a new settings

To change default permissions permanently go to /etc/profile file and edit settings