Portability of "mv -f"

[Pavel Roskin]

Hello!

How portable is "mv -f" used in autoheader.sh? If it is, I believe we
should switch to using it everywhere to avoid any unwanted interactivity.
Otherwise, it should be replaced with "rm -f" and "cp".

Related question - how portable is "mv" across mount points, i.e. between
$TMPDIR and the current directory? Will "mv -f" help?

Perhaps I'm too paranoid, but I just want consistency. I often avoided "mv
-f" in my makefiles because Autoconf didn't use it. Now it does, but only
in one place.

Regards,
Pavel Roskin