How to Manage File and Folder Permissions in Linux

Command line: File permissions

The commands for modifying file permissions and ownership are:

chmod – change permissions

chown – change ownership.

• chmod – the command to modify permissions
• R – this modifies the permission of the parent folder and the child objects within
• ugo+rw – this gives User, Group, and Other read and write access.

The breakdown of permissions looks like this:

• u – user
• g – group
• o – other

The 'other' entry is the dangerous one, as it effectively gives everyone permission for the folder/file. The permissions you can give to a file or folder are:

• r – read
• w – write
• x – execute

Using the -R switch is important. If you have a number of sub-folders and files within the SHARE directory, and you want the permissions to apply from the parent object (the containing folder) to the child objects (the sub-folders and files), you must use the -R (recursive) switch so the same permissions are applied all the way to the deepest folder, contained within the parent.

Command line: File ownership

sudo chown -R bethany /DATA/SHARE

• chown – the command for changing ownership
• R – the recursive switch to make sure all child objects get the same ownership changes
• bethany – the new owner of the folder
• /DATA/SHARE – the directory to be modified