cdif is a post-processor of the Unix diff command. It highlights deleted, changed and added words based on word context. You may want to compare character-by-character rather than word-by-word. Option -B option can be used for that purpose. If only one file is specified, cdif reads that file (stdin if no file) as a output from diff command. Lines those don't look like diff output are simply ignored and printed. Note that this requires fdescfs(5) mounted. WWW: https://github.com/kaz-utashiro/cdif