From mboxrd@z Thu Jan  1 00:00:00 1970
From: Junio C Hamano <gitster@pobox.com>
Subject: Re: [PATCH] git daemon: avoid calling syslog() from a signal handler
Date: Sat, 05 Jul 2008 00:34:04 -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.1.00.0807031624020.9925@racer> (Johannes
 Schindelin's message of "Thu, 3 Jul 2008 16:27:24 +0100 (BST)")
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Johannes Schindelin <Johannes.Schindelin@gmx.de> writes:

> Signal handlers should never call syslog(), as that can raise signals
> of its own.
>
> Instead, call the syslog() from the master process.

Earlier parts seem to make sense but I am puzzled by these changes.

> @@ -929,7 +945,8 @@ static int service_loop(int socknum, int *socklist)
>  	for (;;) {
>  		int i;
>  
> -		if (poll(pfd, socknum, -1) < 0) {
> +		i = poll(pfd, socknum, 1);
> +		if (i < 0) {
>  			if (errno != EINTR) {
>  				error("poll failed, resuming: %s",
>  				      strerror(errno));
> @@ -937,6 +954,10 @@ static int service_loop(int socknum, int *socklist)
>  			}
>  			continue;
>  		}
> +		if (i == 0) {
> +			check_dead_children();
> +			continue;
> +		}

So you will check every 1ms to see if there are new dead children, but why
is this necessary?