From alsa-devel-owner@alsa.jcu.cz  Fri Nov  6 10:34:32 1998
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Date: Fri, 6 Nov 1998 10:25:37 +0100 (CET)
From: Jaroslav Kysela <perex@jcu.cz>
To: Andrew Clausen <clausen@alphalink.com.au>
cc: alsa list <alsa-devel@jcu.cz>
Subject: Re: mmap
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On Fri, 6 Nov 1998, Andrew Clausen wrote:

> Hi,
> 
> What are the arguments for and against mmap()?  I would have thought
> that
> its a Good Thing, because it allows memory used for DMA buffers (for
> example) to be accessed directly by the application.
> 
> Is mmap() supported by ALSA?

mmap() isn't good thing.. You can only save only one sample copy between
user and you cannot do things like sample converting for non-standard
hardware such as SoundBlaster 16, GUS GF1 etc.... Realtime scheduling
gives good latency for playback and record at current time...

							Jaroslav

-----
Jaroslav Kysela <perex@jcu.cz>
Academic Computer Centre, University of South Bohemia
Branisovska 31, C. Budejovice, CZ-370 05 Czech Republic


