Hallo, Bob Rossi hat gesagt: // Bob Rossi wrote: > I am *really* interested to see if dmix is right for me. > > I have been setting up my sound system in Linux for 2 weeks now. I've > got it to the point where I can play sounds and use the MIC. I really > want to get all of the applications to work without using a sound > daemon. > > I am frustrated with the documentation regarding dmix and so far, have > only heard that people have not got dmix to do what I want it to. I am > hoping that dmix is the solution to my sound daemon problems. > > My questions are... > > 1. Does dmix get between /dev/dsp and the sound driver to do > mixing at the software level?
Well, /dev/dsp is part of "the old" sound architecture on Unix, that has been implemented on Linux in the OSS kernel sound system. ALSA is the new Linux sound system and it still provides backwards compatible /dev/dsp devices. ALSA also provides it's own devices or PCMs, which can be extended in various ways that in general are much more flexible than the OSS layer was. One of these devices is the dmix plugin. It enables sound mixing even on hardware that doesn't support this directly. BUT: to use ALSA dmix you have to use software that is ALSA enabled. You cannot use old OSS software with the ALSA devices, unless you convince this software to use ALSA instead of OSS. There are mainly two way to achieve this: 1) rewrite the software or 2) swindle and cheat the software to let it *think* that it uses OSS devices when it is in fact using an ALSA device. 2 is, what the aoss-library does. So: No, dmix technically does not "get between /dev/dsp and the sound driver", but aoss gets between the application and the real /dev/dsp and routes the audio data over to ALSA's dmix. > 2. Can I set up my machine so that this happens? You should be able to set it up like I described. > 3. Will this allow N applications to open /dev/dsp, so I can run more > than one application that produces sound at a time. Yes, that's the goal. It already works with a lot of software that directly uses ALSA. Depending on your needs you might want to take a look at JACK, too, if you're into low latency inter-application sound sharing. > 4. How does the other /dev/ music devices fit into this? With ALSA you should care so much with the /dev thingies, but more with the PCM devinitions. You don't really need to think in terms of /dev/snd anymore. Better think in terms of "plug devices" linke "hw:0", "default" or "plughw:surround51" > 5. Has anyone ever got this to work? I now almost have this working with the last asoundrc I posted. I hope to fix the remaining problems tomorrow with Jaroslav's recent advices, but of course there still *could* be bugs in several places, for example in the sound applications. ciao -- Frank Barknecht _ ______footils.org__ ------------------------------------------------------- This SF.net email sponsored by: Enterprise Linux Forum Conference & Expo The Event For Linux Datacenter Solutions & Strategies in The Enterprise Linux in the Boardroom; in the Front Office; & in the Server Room http://www.enterpriselinuxforum.com _______________________________________________ Alsa-user mailing list [EMAIL PROTECTED] https://lists.sourceforge.net/lists/listinfo/alsa-user
