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From: Junio C Hamano <gitster@pobox.com>
Subject: Re: [PATCH] git daemon: avoid calling syslog() from a signal handler
Date: Sat, 05 Jul 2008 10:26:57 -0700
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Cc: Brian Foster <brian.foster@innova-card.com>, git@vger.kernel.org
To: Johannes Schindelin <Johannes.Schindelin@gmx.de>
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In-Reply-To: <alpine.DEB.1.00.0807051201320.3334@eeepc-johanness> (Johannes
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Johannes Schindelin <Johannes.Schindelin@gmx.de> writes:

>> So you will check every 1ms to see if there are new dead children, but why
>> is this necessary?
>
> This comes from me not reading the man page for poll() properly.  Of 
> course, I want to check every second: syslog timestamps the messages with 
> a resolution of 1 second, AFAIR, or at least some of them do.

Hmm.

The question was not about the millisecond typo, but about why time-out at
all.

We would need to somehow break out of poll() after handling the SIGCHLD
signal and I guess timing the syscall out would be the most obvious way,
but somehow it felt awkward.

Another way would be to set up a pipe to ourself that is included in the
poll() and write a byte to the pipe from the signal handler.