From: Tom Lane <tgl@sss.pgh.pa.us>
To: Andres Freund <andres@anarazel.de>
cc: pgsql-hackers@postgresql.org, Magnus Hagander <magnus@hagander.net>
Subject: Re: pg_basebackup WAL streamer shutdown is bogus - leading to slow tests
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Comments: In-reply-to Andres Freund <andres@anarazel.de>
	message dated "Sun, 16 Jan 2022 01:22:07 -0800"
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Date: Sun, 16 Jan 2022 11:34:42 -0500
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Andres Freund <andres@anarazel.de> writes:
> I don't immediately see a solution for this, other than to add
> StreamCtl->stop_event (mirroring ->stop_socket) and then convert
> CopyStreamPoll() to use WaitForMultipleObjects().  Microsoft's select()
> doesn't support pipes and there's no socketpair().
> Any more straightforward ideas?
> From a cursory look at history, it used to be that pg_basebackup had this
> behaviour on all platforms, but it got fixed for other platforms in
> 7834d20b57a by Tom (assuming the problem wasn't present there).

Hmm --- I see that I thought Windows was unaffected, but I didn't
consider this angle.

Can we send the child process a signal to kick it off its wait?

			regards, tom lane