OSS

Kernel

Device Drivers  --->
        <M> Sound card support  --->
             --- Sound card support
             < >   Advanced Linux Sound Architecture --->
             < >   Open Sound System (DEPRECATED)  --->

Ebuild

There are many more or less active overlays for ebuilds. Most of them require layman to have git or mercurial support:

Alternatively, repositories that use git can benefit from Portage's native git sync support and the eselect repository command:

Install

Build the modules and add /etc/init.d/oss to the default runlevel:

Compatibility

• Many application only provide support for ALSA, therefore it is a good idea to keep both USE flags

USE="... alsa oss ..."

OSS will create ALSA devices for those applications.

• to be able to use OSS4 with GNOME or other gstreamer dependent desktop environments like xfce4. Once again, media-plugins/gst-plugins-oss4 which is included in media-libs/gst-plugins-good! was dropped from the official tree, so you will have to make your own ebuild (quite easy for this one) or else grab one somewhere (bar-overlay, for example).

CMI878x

Unlike ALSA, OSS4 has fewer complex options to configure, so you won't need any `soundon.user'. Especially if your setup isn't complex or are using more than one sound card. In the latter case, you may want to keep a `soundon.user' file to be able to choose your first card (default card). And then, insert a few lines correcting devices nodes which can be problematic.

<syntaxhighlight lang="bash">#!/bin/sh
# $ID: /usr/lib/oss/soundon.user, 2012/07/27 12:57:40 -tclover Exp $
modprobe -a oss_{cmi878x,hdaudio}
/usr/sbin/ossdetect -diu
/usr/sbin/ossdevlinks 
# Remapping ossdevlinks links
if [ -d /dev/oss/oss_cmi878x ]; then
	ln -sf /dev/oss/oss_cmi878x0/pcm1 /dev/dsp
	ln -sf /dev/oss/oss_cmi878x0/pcm1 /dev/dsp_ac3
	ln -sf /dev/oss/oss_cmi878x0/pcm1 /dev/dsp_in
	ln -sf /dev/oss/oss_cmi878x0/pcm1 /dev/dsp_mmap
	ln -sf /dev/oss/oss_cmi878x0/pcm1 /dev/dsp_multich
	ln -sf /dev/oss/oss_cmi878x0/pcm1 /dev/dsp_out
	vmixctl attach /dev/oss/oss_cmi878x0/pcm1 /dev/oss/oss_cmi878x0/pcm1
else
	ln -sf /dev/oss/oss_hdaudio0/pcm0 /dev/dsp
	ln -sf /dev/oss/oss_hdaudio0/pcmin0 /dev/dsp_in
#	ln -sf /dev/oss/oss_hdaudio0/spdout0 /dev/dsp
	ln -sf /dev/oss/oss_hdaudio0/spdout0 /dev/dsp_ac3
#	ln -sf /dev/oss/oss_hdaudio0/spdin0 /dev/dsp_in
	ln -sf /dev/oss/oss_hdaudio0/spdout0 /dev/dsp_mmap
	ln -sf /dev/oss/oss_hdaudio0/spdout0 /dev/dsp_multich
	ln -sf /dev/oss/oss_hdaudio0/spdout0 /dev/dsp_out
#	vmixctl attach /dev/oss/oss_hdaudio0/pcm0 /dev/oss/oss_hdaudio0/pcmin0
fi
# vim:fenc=utf-8:ft=sh:ci:pi:sts=0:sw=2:ts=2:</syntaxhighlight>

The previous script will check if there are devices nodes, so a sound card, with CMI878x driver and then relink almost everything to it or else use HDAudio.

CONFIG_PROTECT="... /usr/lib/oss/soundon.user ..."

Or else, create a file like `~/.scripts/soundon.user' and edit `/etc/init.d/oss' to your liking.

<syntaxhighlight lang="bash">/usr/sbin/soundon
/root/.scripts/soundon.user
/usr/sbin/savemixer -L</syntaxhighlight>

Now you can enjoy Open Sound System. I found the sound with OSS4 to be better than what I can get with ALSA. There was a time when my CMI878x sound works only with OSS4 but a few things changed.

OSS4 has its own mixer so using extra sound daemons like pulseaudio, esd etc. is not necessary.

osstest

Maybe it just works, test all audio devices with the following command:

ossxmix

ossxmix is the graphical tool to configure devices: