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From: Eli Zaretskii <eliz@gnu.org>
Newsgroups: gmane.emacs.devel
Subject: Re: scratch/sigchld-fd 8f0ce42 1/2: Fix deadlock when receiving
 SIGCHLD during 'pselect'.
Date: Wed, 20 Jan 2021 10:52:07 +0200
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On January 20, 2021 10:37:31 AM GMT+02:00, Andreas Schwab <schwab@linux-m68=
k=2Eorg> wrote:
> On Jan 20 2021, Eli Zaretskii wrote:
>=20
> > AFAIU, this is an issue for programs that install a SIGCHLD handler
> > immediately before calling pselect=2E  But Emacs has a SIGCHLD handler
> > installed at all times, so if the signal hits outside of the pselect
> > call, we should be able to detect that reliably=2E
>=20
> No, the race between checking for the signal and entering pselect
> still
> exists=2E

Please tell more, especially what is meant by "checking for the signal"=2E=
  We have a handler installed, so who is or should be checking for it?