Re: diffutils 2.8 and -u/-U options

[Karl Berry]

    > Is there an environment variable that one can set to make diff ignore
    > these POSIX silliness

Indeed, I set
  _POSIX2_VERSION=0
because of precisely this problem.  vc-mode on RCS files no longer
works in the latest Emacs (not that that's very late) with the latest
diff otherwise.

I was annoyed with POSIX, as usual, that it was necessary, but I was
grateful that the envvar could be set, so I did not have to hack the
source (of either emacs or diff or both).

(In my opinion (and the opinion of the GNU coding standards) this sort
of thing is exactly what POSIXLY_CORRECT was intended for.  Oh well ...)

karl