rdiff

Synopsis: rdiff [OPTIONS] PROJECTS

• Alternate names – patch, pa
• Requires – Repository
• Changes – Nothing

Like the diff command, except it operates directly in the repository and, therefore, requires no working copy. This command is meant for obtaining the differences between one release and another of your project, in a format suitable as input to the patch program (perhaps so you can distribute patch files to users who want to upgrade).

The operation of the patch program is beyond the scope of this book. However, note that if the patch file contains diffs for files in subdirectories, you may need to use the -p option to patch to get it to apply the differences correctly. (See the patch documentation for more about this.) (See also diff.)

Options:

• -c – Prints output in context diff format (the default).
• -D DATE or -D DATE1 -D DATE2 – With one date, this shows the differences between the files as of DATE and the head revisions. With two dates, it shows the differences between the dates.
• -f – Forces the use of head revision if no matching revision is found for the -D or -r flag (otherwise, rdiff would just ignore the file).
• -l – Local. Won't descend into subdirectories.
• -R – Recursive. Descends into subdirectories (the default). You only specify this option to counteract a -l in your .cvsrc.
• -r REV -r REV1 -r REV2 – With one revision, this shows the differences between revision REV of the files and the head revisions. With two, it shows the differences between the revisions.
• -s – Displays a summary of differences. This shows which files have been added, modified, or removed, without showing changes in their content. The output looks like this:

            floss$ cvs -Q rdiff -s -D 1999-08-20 myproj
            File myproj/Random.txt is new; current revision 1.4
            File myproj/README.txt changed from revision 2.1 to 2.20
            File myproj/baar is new; current revision 2.3
       

• -t – Shows the diff between the top two revisions of each file. This is a handy shortcut for determining the most recent changes to a project. This option is incompatible with -D and -r.
• -u – Prints output in unidiff format. Older versions of patch can't handle unidiff format; therefore, don't use -u if you're trying to generate a distributable patch file – use -c instead.
• -V (Obsolete) – CVS reports an error if you try to use this option now. I've included it here only in case you see some old script trying to use it.