GNU bug report logs - #17036
Continuation for Emacs: invoking a process on exit?

Previous Next

Full log

View this message in rfc822 format

From: Eli Zaretskii <eliz <at> gnu.org>
To: Reuben Thomas <rrt <at> sc3d.org>
Cc: 17036 <at> debbugs.gnu.org, schwab <at> linux-m68k.org, monnier <at> iro.umontreal.ca
Subject: bug#17036: Continuation for Emacs: invoking a process on exit?
Date: Thu, 20 Mar 2014 05:45:18 +0200

> Date: Wed, 19 Mar 2014 21:14:22 +0000
> From: Reuben Thomas <rrt <at> sc3d.org>
> Cc: Stefan Monnier <monnier <at> iro.umontreal.ca>, Andreas Schwab <schwab <at> linux-m68k.org>, 
> 	17036 <at> debbugs.gnu.org
> 
> > Don't believe the sales people.  MS's execvp is buggy, and even if we
> > forget about those bugs, it won't do what is expected here: it won't
> > keep the file descriptors open in the original process still open in
> > the overlaid process.  That's because there's no 'exec' system call on
> > Windows, so execvp is _emulated_: the original process simply invokes
> > the new one as its child process, and then immediately exits.
> >
> 
> That's good enough for restart-emacs.

Maybe so, it's hard to say, since you never described what that should
do.

> > So the answer to Stefan is: no, this cannot be done on Windows, not
> > without some custom code to let the re-executed Emacs inherit all of
> > the file descriptors which were open in the original Emacs process.
> >
> 
> It's fine for what i had in mind, namely Emacs simply launching another
> command with arguments, much as a Lisp callcc. This could be documented as
> a limitation on Windows.

I very much doubt that this limitation would not render the whole
issue moot on Windows.  E.g., how will restart-emacs then be different
from a simple call-process?  But again, since you didn't say what the
feature is supposed to do, ...

Previous Next

GNU bug tracking system
Copyright (C) 1999 Darren O. Benham, 1997,2003 nCipher Corporation Ltd, 1994-97 Ian Jackson.