From mboxrd@z Thu Jan  1 00:00:00 1970
From: Clemens Ladisch <clemens@ladisch.de>
Subject: Re: ioctl(arg) - uninitialised byte(s) in alsa lib
Date: Wed, 12 Mar 2008 13:15:43 +0100
Message-ID: <47D7C96F.8010109@ladisch.de>
References: <47D7C358.6050401@xwaves.net>
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To: Mathieu Monney <zittix_all@xwaves.net>
Cc: alsa-devel@alsa-project.org
List-Id: alsa-devel@alsa-project.org

Mathieu Monney wrote:
> I'm currently working on a small audio stack on top of alsa and I'm
> getting some "Syscall param ioctl(arg) contains uninitialized byte(s)"
> errors when I run my program using valgrind.
>
> ==14279==    by 0x40DE911: snd_pcm_prepare (in /usr/lib/libasound.so.2.0.0)

The ioctl call is in src/pcm/pcm_hw.c:

	if (ioctl(fd, SNDRV_PCM_IOCTL_PREPARE) < 0) {

Apparently, valgrind doesn't detect the cases where there is no third
argument.


Regards,
Clemens