io-audio

Start an audio driver

You must be root to start this manager.

Syntax:

io-audio [-d driver [driver_options]] [-o opt[,opt[,opt]]]
         [v[v]...]

Options:

-d driver [driver_options]
Load the specified driver and pass it the given driver_options. For information on the drivers and their syntax and options, see the deva-* entries.
-o global_options
Global options. The global_options variable can be any of the following:
  • config_write_delay= time

    The time in seconds after the last change before soundcard settings are written to disk, (a value of -1 prevents the settings from ever being written).

  • max_dma_buf_size= size

    The maximum size, in kilobytes, for the DMA buffer.

  • disable_sw_mixer

    On cards that have only a single channel in hardware, do not use software techniques to increase the maximum number of playing channels.

See the list of shared objects (below) for details about local options for specific drivers.
-v
Increase the level of verbose output.

Description:

The io-audio manager provides support for dynamically loaded audio-driver modules. This utility enables you to load the audio drivers specified by the -d options when you start io-audio.

  • You can start more than one driver by using multiple -d command-line options, but don't try to start more than one instance of io-audio.
  • Graphics drivers run at a higher priority than applications, but they shouldn't run at a higher priority than the audio, or else breaks in the audio occur. You can use the on command to adjust the priorities of the audio and graphics drivers.

Once io-audio has started, you can dynamically load and unload drivers using the mount and umount commands. E.g. this command:

io-audio -dvortex -daudiopci &

gives the same result as this sequence:

io-audio &
mount -T io-audio vortex
mount -T io-audio audiopci
When searching for shared objects, the io-audio manager uses the LD_LIBRARY_PATH environment variable.

To unload a module, use a command like this:

umount /dev/snd/controlC0

Examples:

Provide support for Aureal Vortex sound card:

io-audio -vv -d vortex &

Files:

The io-audio command can load the following shared objects:

deva-mixer-ac97.so
Mixer DLL for the AC97 codec.