[hackers] Re: [dwm][PATCH v2] Use sigaction(SA_NOCLDWAIT) for SIGCHLD handling

From: Chris Down <chris_AT_chrisdown.name>
Date: Tue, 20 Sep 2022 15:52:33 -0400

Hey Hiltjo,

Chris Down writes:
>signal() semantics are pretty unclearly specified. For example,
>depending on OS kernel and libc, the handler may be returned to SIG_DFL
>(hence the inner call to readd the signal handler). Moving to
>sigaction() means the behaviour is consistently defined.
>
>Using SA_NOCLDWAIT also allows us to avoid calling the non-reentrant
>function die() in the handler.
>
>waitpid() and sigaction() can also fail with EINTR, which may mean our
>zombie handling fails, so block signals while setting things up to be
>careful.

I think this one is good to go -- me and NRK seem to agree about everything
now, and there wasn't any other feedback as far as I'm aware.

Any other feedback blocking merge that I may have missed?

Thanks!

Chris
Received on Tue Sep 20 2022 - 21:52:33 CEST