Hi Oko,
QEMU_OSS_DAC_DEV and
QEMU_OSS_ADC_DEV just happen to be
/dev/dsp by default.. a common Linuxism.
Code:
$ qemu -audio-help
Audio options:
QEMU_AUDIO_DAC_FIXED_SETTINGS: boolean, default = 1
Use fixed settings for host DAC
QEMU_AUDIO_DAC_FIXED_FREQ: integer, default = 44100
Frequency for fixed host DAC
QEMU_AUDIO_DAC_FIXED_FMT: format, default = S16, (one of: U8 S8 U16 S16)
Format for fixed host DAC
QEMU_AUDIO_DAC_FIXED_CHANNELS: integer, default = 2
Number of channels for fixed DAC (1 - mono, 2 - stereo)
QEMU_AUDIO_DAC_VOICES: integer, default = 1
Number of voices for DAC
QEMU_AUDIO_ADC_FIXED_SETTINGS: boolean, default = 1
Use fixed settings for host ADC
QEMU_AUDIO_ADC_FIXED_FREQ: integer, default = 44100
Frequency for fixed host ADC
QEMU_AUDIO_ADC_FIXED_FMT: format, default = S16, (one of: U8 S8 U16 S16)
Format for fixed host ADC
QEMU_AUDIO_ADC_FIXED_CHANNELS: integer, default = 2
Number of channels for fixed ADC (1 - mono, 2 - stereo)
QEMU_AUDIO_ADC_VOICES: integer, default = 1
Number of voices for ADC
QEMU_AUDIO_TIMER_PERIOD: integer, default = 0
Timer period in HZ (0 - use lowest possible)
QEMU_AUDIO_PLIVE: boolean, default = 0
(undocumented)
QEMU_AUDIO_LOG_TO_MONITOR: boolean, default = 0
print logging messages to montior instead of stderr
Available drivers:
Name: oss
Description: OSS http://www.opensound.com
Theoretically supports many playback voices
Theoretically supports many capture voices
Options:
QEMU_OSS_FRAGSIZE: integer, default = 4096
Fragment size in bytes
QEMU_OSS_NFRAGS: integer, default = 4
Number of fragments
QEMU_OSS_MMAP: boolean, default = 0
Try using memory mapped access
QEMU_OSS_DAC_DEV: string, default = /dev/dsp
Path to DAC device
QEMU_OSS_ADC_DEV: string, default = /dev/dsp
Path to ADC device
QEMU_OSS_DEBUG: boolean, default = 0
Turn on some debugging messages
Name: sdl
Description: SDL http://www.libsdl.org
One playback voice
Does not support capture
Options:
QEMU_SDL_SAMPLES: integer, default = 1024
Size of SDL buffer in samples
Name: none
Description: Timer based audio emulation
Theoretically supports many playback voices
Theoretically supports many capture voices
No options
Name: wav
Description: WAV renderer http://wikipedia.org/wiki/WAV
One playback voice
Does not support capture
Options:
QEMU_WAV_FREQUENCY: integer, default = 44100
Frequency
QEMU_WAV_FORMAT: format, default = S16, (one of: U8 S8 U16 S16)
Format
QEMU_WAV_DAC_FIXED_CHANNELS: integer, default = 2
Number of channels (1 - mono, 2 - stereo)
QEMU_WAV_PATH: string, default = qemu.wav
Path to wave file
Options are settable through environment variables.
Example:
export QEMU_AUDIO_DRV=wav
export QEMU_WAV_PATH=$HOME/tune.wav
(for csh replace export with setenv in the above)
qemu ...
So you can either
export QEMU_AUDIO_DRV=sdl or
export QEMU_OSS_{ADC,DAC}_DEV=/dev/audio.
Hope that helps.