Instead of using a compare editor, which will show changes between 2 or 3 files by showing each file side-by-side, you can enable quick diff support and see the changes within the text editor (e.g. any text editor based on the Eclipse text editor). This feature can be enabled via the General > Editors > Text Editors > Quick Diff preference page. You should select the Latest CVS Revision as the reference source. This will annotate the text file with diffs against the latest revision in CVS. Here are the following scenarios that are useful:
Open a file and make changes to it. You will see the difference annotations marking the changes. Then if you run Team > Replace with latest. The annotations are removed and the file is clean.
Open a file and make changes to it. You will see the difference annotations marking the changes. Then if you run Team > Commit the annotations are removed and the file is clean.
If you synchronize the file with the server and a new revision is found on the server, the editor will update showing the incoming changes.
If you enable showing the differences in the overview ruler, you can, at a glance, get an idea of how many changes you have made to a file since your last commit. The differencing happens in a background thread to minimize the impact on actual editing of the file.
Note: this feature requires an active connection to your CVS server so that remote contents can be fetched when an editor is opened.