After making edits to the file, RCS can display the difference between the working file and the latest version. This is helpful when a file has been edited since you last checked it out and see the specific changes made to a file.

The name of the command is rcsdiff. rcsdiff takes the same options as the diff command (see manual on diff). The general form of such a command is:

$ rcsdiff our_file.txt
===================================================================
RCS file: RCS/our_file.txt,v
retrieving revision 1.1
diff -r1.1 our_file.txt
1a2
> Which of it is ours?

The output of rcsdiff is the default output for the system's diff command. For this example, the output is the ed format.