io-audio

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Caution: This version of this document is no longer maintained. For the latest documentation, see http://www.qnx.com/developers/docs.

io-audio

Start an audio driver


Note: You must be root to start this manager.

Syntax:

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

Runs on:

Neutrino

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:
Driver: Shared object:
4dwave deva-ctrl-4dwave.so
audiopci deva-ctrl-audiopci.so
cs4281 deva-ctrl-cs4281.so
cs46xx deva-ctrl-cs46xx.so
ess1938 deva-ctrl-ess1938.so
geode deva-ctrl-geode.so
i8x0 deva-ctrl-i8x0.so
nmg6 deva-ctrl-nmg6.so
via686 deva-ctrl-via686.so
vortex deva-ctrl-vortex.so
ymfds1 deva-ctrl-ymfds1.so
-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.


Note: 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.


Note: 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.

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

Note: 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-ctrl-4dwave.so
Sound driver for the Trident 4DWave!.
deva-ctrl-audiopci.so
Sound driver for the AudioPCI chip family.
deva-ctrl-cs4281.so
Sound driver for the CS4281.
deva-ctrl-cs46xx.so
Sound driver for the CS46xx family of chips.
deva-ctrl-ess1938.so
Sound driver for the ESS1938.
deva-ctrl-geode.so
Sound driver for the National Semiconductor Geode family of chips.
deva-ctrl-i8x0.so
Sound driver for the Intel 8X0.
deva-ctrl-nmg6.so
Sound driver for the Neomagic 6 family of chips.
deva-ctrl-via686.so
Sound driver for the VIA686.
deva-ctrl-vortex.so
Sound driver for the Vortex.
deva-ctrl-ymfds1.so
Sound driver for the Yamaha DS1.
deva-mixer-ac97.so
Mixer DLL for the AC97 codec.
deva-ak4531.so
Mixer DLL for the AK4531 codec.
deva-util-restore.so
Shared object used to restore an audio driver's state.

See also:

Connecting Hardware in the Neutrino User's Guide