From mboxrd@z Thu Jan  1 00:00:00 1970
From: Paolo Bonzini <bonzini@gnu.org>
Subject: Re: poll() emulation in git
Date: Thu, 06 Sep 2012 17:15:02 +0200
Message-ID: <5048BDF6.2000602@gnu.org>
References: <00c001cd8b59$028e41c0$07aac540$@schmitz-digital.de> <50474001.5030407@gnu.org> <00d801cd8b6b$844bbcd0$8ce33670$@schmitz-digital.de> <50476EFD.2000500@gnu.org> <010301cd8c38$4256bb90$c70432b0$@schmitz-digital.de> <5048B3D0.2070809@gnu.org> <010a01cd8c3e$25609500$7021bf00$@schmitz-digital.de>
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Cc: git@vger.kernel.org, 'Junio C Hamano' <gitster@pobox.com>,
	'Erik Faye-Lund' <kusmabite@gmail.com>, bug-gnulib@gnu.org,
	rsbecker@nexbridge.com
To: Joachim Schmitz <jojo@schmitz-digital.de>
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Il 06/09/2012 16:44, Joachim Schmitz ha scritto:
>> > Yes, it's an usleep(autocorrect * 100000) basically (poll takes
>> > milliseconds, not micro).
> OK, it is _supposed_ to do this usleep(), but is does not, as poll() returns early with EFAULT in this case:
>   /* EFAULT is not necessary to implement, but let's do it in the
>      simplest case. */
>   if (!pfd)
>     {
>       errno = EFAULT;
>       return -1;
>     }
> 
> poll() is doing this before calling select(), so won't sleep.
> So there's a bug in {gnulib|git}'s poll(), right?
> 

Yes, it should be "if (!pfd && nfd)".

Paolo