From mboxrd@z Thu Jan  1 00:00:00 1970
From: Vinod Koul <vinod.koul@intel.com>
Subject: Re: How does ALSALIB commuciates with low level kernel
 API
Date: Mon, 20 Jun 2016 23:13:52 +0530
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To: Chemsi Mehdi <chmsmehdi@gmail.com>
Cc: alsa-devel@alsa-project.org
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On Wed, Jun 15, 2016 at 12:12:24AM +0100, Chemsi Mehdi wrote:
> Dear experts,
> 
> I am too new in ALSA, trying to read a little bit and understand.
> I want to underatnd how ALSA userspace API calls kernel space code ?
> for example when I call  snd_pcm_open() which code is called in kernel
> sound code ?

easist would be to start gdb on alsa-lib snd_pcm_open() and start tracing
the steps.


> and how the link is made ? via IOCTL/write ?

IOCTL, see sound/core/pcm_native.c on kernel side..

-- 
~Vinod