sudo yum install meld
meld is basically a diff viewer and pretty good at it 😉
Now open meld from the menu or from the terminal. And then select New. In the dialog box that appears select “Version Control Browser”. In the Directory box, browse to the folder where you have the code checked out and select ok. And you are all set.
To see the diff with cvs version just double click.
Note: If you are getting issues when you double click, ensure that you do not have any commands for diff in .cvsrc file.
There are other ways of doing this, but thats for some other day.