Re: scratch/sigchld-fd 8f0ce42 1/2: Fix deadlock when receiving SIGCHLD during 'pselect'.

[Eli Zaretskii]

On January 20, 2021 11:18:19 AM GMT+02:00, Andreas Schwab 
<schwab@linux-m68k.org> wrote:
> On Jan 20 2021, Eli Zaretskii wrote:
> 
> > Please tell more, especially what is meant by "checking for the
> signal".  We have a handler installed, so who is or should be checking
> for it?
> 
> The check that the signal occured and what to pass to pselect so it
> doesn't block waiting for the condition that just occured.

If/when the signal arrives, the handler removes the file descriptor of the 
process from the set on which pselect will wait.  Isn't that sufficient to 
prevent us from waiting for a dead process?
If not, why not?