Changing User Ownership
To apply appropriate permissions, the first thing to consider is ownership. To do this, there is the chown command. The syntax of this command is not hard to understand:
■ chown who what
For instance, the following command changees ownership for the file account to user linda:
■ chown linda account
The chown command has a few options, of which one is particularly useful: -R . You might guess what it does, because this option is available for many other commands as well. It allows you to set ownership recursively, which allows you to set ownership of the current directory and everything below. The following command changes ownership for the directory /home and everything beneath it to user linda:
■ chown -R linda /home/linda
Changing Group Ownership
There are actually two ways to change group ownership. You can do it using chown , but there is also a specific command with the name chgrp that does the job. If you want to use the chown command, use a . or : in front of the group name. The following changes the group owner of directory /home/account to the group account:
chown .account /home/account
You can use chown to change user and/or group ownership in a number of ways, an overview of which follows:
■ chown lisa myfile Sets user lisa as the owner of myfile
■ chown lisa.sales myfile Sets user lisa as user owner and group sales as group owner of myfile
■ chown lisa:sales myfile Sets user lisa as user owner and group sales as group owner of myfile
■ chown .sales myfile Sets group sales as group owner of myfile without changing the user owner
■ chown :sales myfile Sets group sales as group owner of myfile without changing the user owner
You can also use the chgrp command to change group ownership. Consider the following example, where you can use chgrp to set group ownership for the directory / home/account to the group account:
■ chgrp account /home/account
As is the case for chown , you can use the option -R with chgrp as well to change group ownership recursively.