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From: Dirk Engling <erdgeist@erdgeist.org>
To: Pawel Jakub Dawidek <pjd@FreeBSD.org>
Subject: Re: pidfile_open incorrectly returns EAGAIN when pidfile is locked
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On Thu, 14 Mar 2013, Pawel Jakub Dawidek wrote:

> Right. Your patch assumes EWOULDBLOCK is equal to EAGAIN, which is true
> on FreeBSD, but is not portable. Also in case pidptr is NULL you compare
> errno three times instead of just one (not a big deal of course, just
> something that could be done a bit more optimal:)).

You're right.

OTOH, wouldn't modifying pidfile_read to return EAGAIN and not EWOULDBLOCK 
totally be worth saving that 2 lines in the patch? ;)

   erdgeist