Re: CEDET calls cpp -E -dM -x c++ /dev/null

[Eli Zaretskii]

> Date: Wed, 1 Jul 2009 21:25:47 +0200
> From: Lennart Borgman <address@hidden>
> Cc: address@hidden, address@hidden, address@hidden
> 
> On Wed, Jul 1, 2009 at 9:20 PM, Eli Zaretskii<address@hidden> wrote:
> >> Date: Wed, 1 Jul 2009 21:06:17 +0200
> >> From: Lennart Borgman <address@hidden>
> >> Cc: Alex Ott <address@hidden>, "Eric M. Ludlam" <address@hidden>
> >>
> >> CEDET does the call above in semantic-gcc-setup. Doing that from the
> >> command line using MingGW on w32 fails.
> >>
> >> It fails because /dev/null is not valid on w32. Shouldn't it be NUL
> >> there?
> >
> > Yes.
> >
> >> However looking through Emacs lisp sources I see several uses
> >> of just /dev/null.
> >
> > They are all bugs, unless they are intended to work only with Unix and
> > GNU systems.
> 
> Thanks Eli. Should we file a bug report for this so it perhaps will
> not be forgotten?

Yes, please.

> >> Wouldn't it be better to use some defsubst for this?
> >
> > We already have one: the Lisp variable null-device holds the name of
> > the device appropriate for the underlying OS.
> 
> I think Info would be glad to know. Somewhere in "Operating System Interface"?

I guess so.  "Operating System Environment" sounds like a good place.
shell-file-name and shell-command-switch should probably be documented
as well.