$ diff --git diff: unrecognized option '--git' I think diff should say at this point "real diff, at least up to year 2010, does not have a --git option, you are probably getting that idea from git output" or something.
That is what it says, though not in so many words. Having an option for each VS would really be a headache (SCCS, RCS, CVS, hg, darcs, bzr, tla, git, ...).
