File Access Permissions - Who may access?

• Access Permissions are split into 3: for the User-owner, the Group-owner and for "others".
• If the User accessing the File is the User-owner of the File, only the "User-owner" permissions are checked.
• Thus, a File with permissions for 'others' but no permissions for 'User-owner' - won't allow the User-owner to access it...
• ...But as we said, the User-owner may always change the permissions of the File, so she can give herself access to the File, and then access the File.
• A similar check is performed if the User accessing the File, belongs to the Group-owner of the File (but is not the User-owner of the File).

Originally written by guy keren