From mboxrd@z Thu Jan  1 00:00:00 1970
From: Clemens Ladisch <clemens@ladisch.de>
Subject: Re: Using MMAP feature
Date: Mon, 23 Jul 2012 12:38:27 +0200
Message-ID: <500D29A3.50204@ladisch.de>
References: <500CF994.5090901@seletech.com>
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To: alberto Villa <a.villa@seletech.com>
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alberto Villa wrote:> Hello,
> I'm going to use the MMAP feature of ALSA.

Why do you need to do this?

> snd_pcm_mmap_begin(capture, &c_area, &c_offset, &c_frames);
>
> it keeps to return c_frames = 0: is it right ? what does this mean?

It means that there are no samples available at the moment.
(Or that you forgot to call snd_pcm_avail_update(), or that you
didn't set c_frames before the call.)


Regards,
Clemens