oss2jack - A Linux kernel based approach to using OSS applications with the Jack Audio Connection Kit

Author: Kor Nielsen <knielsen@xdas.com>

oss2jack uses Jeremy Elson's useful fusd library to create a userspace character device, which is also a jackd client. It supports mono and stereo streams, with virtually any sample rate thanks to libsamplerate. Only the commonly-used OSS ioctls are currently supported.


May 8, 2007 - fusd updates

Monty at xiph.org has been leading a push to get fusd included in the linux kernel, intended for use with oss2pulse. He has imported my fork (with some important changes) into the xiph subversion repository at http://svn.xiph.org/trunk/fusd/. Those of you looking for compatibility with the latest kernels would be best to start there.

May 2, 2006 - New Releases of oss2jack and fusd

fusd-kor-1.10-11 fixes issues compiling with the 2.6.15 kernel. oss2jack-0.25 adds the following new features:

Oct 30, 2005 - fusd updates

Quite a few people seem to have problems with the status device not showing up with newer versions of gentoo's udev. Fortunately, this device is only used for diagnostics and is not actually used by oss2jack.

Also, the fusd samples do not function correctly with udev, as they are trying to create devices by name rather than class. fusd-kor (with udev) is only known to work correctly with oss2jack at this time.

Sept 22, 2005 - Mailing list

Thanks to user demand, there is now an oss2jack-user mailing list.

Sept 18, 2005 - New Release

oss2jack-0.24 fixes a few minor bugs preventing smooth operation with asterisk. In addition, oss2jack can now host jackd, allowing you to run a long chain of oss2jack / jackd processes. :)

Sept 17, 2005, - New Release / Documentation

oss2jack-0.23 features some input fixes, as well as a working implementation of SNDCTL_DSP_CHANNELS.

fusd-kor-1.10-10 now works with kernel 2.6.13. Backwards compatibility is yet to be tested, so if it doesn't work on earlier kernels, use fusd-kor-1.10-9.

I have finally released some detailed installation instructions. These instructions are biased towards Ubuntu, but users of other distributions should be able to get some use out of them as well.

Jun 18, 2005 - New Release

New features:

oss2jack-0.21 requires my latest fusd hack, fusd-kor-1.10-9. Please install the latest version of fusd before compiling oss2jack.

Jun 12, 2005 - Development Update

New features in subversion:

I have discovered an issue with the software package audacity. Audacity's UI hangs when playing audio through oss2jack. This appears to be caused by a fusd limitation with regards to simultaneous writes and ioctls from seperate threads. I have a preliminary fix for fusd, which I will release when I am comfortable with its stability.

After running various development versions of oss2jack over the course of a week, I noticed the memory usage of my machine slowly increasing. I suspect there is a memory leak in the fusd kernel module. If anyone else has seen similar issues, please let me know.

Jun 5, 2005

I have set up a public Subversion repository for oss2jack. To check out the latest development version of oss2jack, run the following command:

   svn co https://fort2.xdas.com/svn/public/oss2jack/trunk oss2jack

Feb 10, 2005

Some users pointed out a major problem with yesterday's fusd release. That version of fusd was mistakingly looking for /dev/.devfsd, and would cause shutdown problems if it wasn't found. That issue should be fixed in version 1-10-8. Remember to recompile oss2jack after upgrading your fusd libraries. I also released a new version of oss2jack which cleans up some compiler warnings.

Feb 9, 2005

I have just released oss2jack 0.14. This new release works with my new udev version of fusd, and implements the SNDCTL_DSP_SETFMT ioctl to allow GStreamer based apps such as rhythmbox to work.

I've added some more hacks to my fusd fork, version 1.10-7. This release works with udev under kernel 2.6 (and should continue to work with devfs, although I haven't tested it).

To get it to work, you will have to put a couple lines at the top of your udev rules file (found at /etc/udev/rules.d/50-udev.rules for Gentoo users):

# fusd devices
KERNEL="control", NAME="fusd/%k"
KERNEL="status", NAME="fusd/%k"

I know this is a little sloppy; I will try to fix it later.

Feb 6, 2005

I recently upgraded to udev from devfs, and now oss2jack no longer runs. I will have to make some modifications to fusd to support udev and/or regular filesystems.



oss2jack has been tested with the following applications:


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