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Date:   Wed, 28 Nov 2018 06:17:37 +0200
From:   Max Kirillov <max@max630.net>
To:     Junio C Hamano <gitster@pobox.com>
Cc:     Max Kirillov <max@max630.net>, peff@peff.net,
        Carlo Arenas <carenas@gmail.com>, git@vger.kernel.org
Subject: Re: [PATCH] t5562: do not reuse output files
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On Mon, Nov 26, 2018 at 11:06:40AM +0900, Junio C Hamano wrote:
> I am offhand not sure what the right value of wait_after_clean for
> this codepath be, though.  46df6906 ("execv_dashed_external: wait
> for child on signal death", 2017-01-06) made this non-default but
> turned it on for dashed externals (especially to help the case where
> they spawn a pager), as the parent has nothing other than to wait
> for the child to exit in that codepath.  Does the same reasoning
> apply here, too?

As far as I understand, the reason to _not_ wait was that
the child might still be expecting closed stdin even after
receiving SIGTERM, so parent would wait forever. But this is
not clearly the case here. And otherwise there should be no
reason to not wait, as long as we are interested in
synchronous exiting of the child.

In my Linux experiments the child was exiting because of signal
earlier than because of closed stdin, but who knows, maybe
with some bad luck the signal would be delivered after the
closed stdin, and we would still have the issue. After all,
at Linux it was mostly working even without fix.