FreeBSD's sound system lineage....

Diane Bruce db at
Mon Jul 23 17:57:25 UTC 2007

On Tue, Jul 24, 2007 at 12:44:48AM +0800, Ariff Abdullah wrote:
> On Mon, 23 Jul 2007 09:28:03 -0700
> Julian Elischer <julian at> wrote:
> > Alexander Leidinger wrote:
> > > Quoting Julian Elischer <julian at> (Mon, 23 Jul 2007
> > > 07:24:36 -0700):
> > >> The OSS people have offered us the use (from memory) of their
> > >ALSA<->OSS > shim library. It would be nice if one of the sound
> > >people > would talk to them and see if the offer still stands.

I looked at that months ago.

> > >
> > > It needs kernel support which we don't have. I don't know how
> > > hard/easy it is to provide this support.

As far as I could see, a simple kqueue shim would handle the event side.

> > That's where we probably need someone like Ariff to have a look at
> > it.
> >
> > I think they also offered to help us get that support.
> >
> ALSA is purely userland stuffs, much like other things like SDL,

Yes. I agree, I believe kqueue would help us here.

> pulseaudio, arts, jack, yada yada, so on. All you need to do is grab
> plain alsa library, replacing alsa kernel call -> oss ioctl (much
> like NetBSD/OpenBSD did with their sunaudio -> liboss), and produce
> appropriate libalsa depending on your target (linux binary for linux

I've got a partial shim already started. My major problem was the docs
for ALSA are terrible, at least the ones I saw. I don't like
trying to navigate a wiki for docs.

> apps). Leveraging hardware features provided by ALSA call is a
> different story, though.

About all I could see ALSA did was it adds the equivalent of our vchans
and an event driven interface. All very overly complex with bells and whistles.

I've started digging through my ALSA code shim. I think I could use help.
I wanted to be GPL clean, I think I am so far. ;-)

Any volunteers?

- Diane
- db at db at

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