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From: Eli Zaretskii <eliz@gnu.org>
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Subject: Re: master 2c79a8f 2/2: Use posix_spawn if possible.
Date: Sat, 26 Dec 2020 14:16:40 +0200
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> Date: Sat, 26 Dec 2020 14:08:11 +0200
> From: Eli Zaretskii <eliz@gnu.org>
> Cc: emacs-devel@gnu.org
> 
> See Savannah bug #59093 for one subtle issue:
> 
>   https://savannah.gnu.org/bugs/?59093
> 
> Since Emacs also sets its stack limit in some cases, this could be
> directly relevant to us.  (But I didn't look into it close enough to
> tell whether it actually is relevant.)

Btw, given this condition for using posix_spawn:

  +  /* `posix_spawn' doesn't yet support setting up pseudoterminals, so
  +     we fall back to `vfork' if we're supposed to use a
  +     pseudoterminal.  */
  +
  +  bool use_posix_spawn = can_use_posix_spawn && pty == NULL;

I understand that the absolute majority of subprocesses on GNU and
Posix platforms will not use posix_spawn, because we usually do use
PTYs?  If so, one wonders why it is a good idea to complicate our code
and make it more dependent on Gnulib, for such small gains?  Should we
perhaps wait until posix_spawn does support PTYs?