Open Sound System
OSS 4.x Programmer's Guide

Do you have problems with sound/audio application development? Don't panic! Click here for help!

DSP_CH_MASK audio device capability

Preferred channel configuration


This capability field (caps&DSP_CH_MASK) returns information about the preferred channel configuration for the device. This field can be used as a hing in some special cases. Normal applications should not check this field.

The following values are possible.

DSP_CH_ANYThere is no preferred channel mode.
DSP_CH_MONOThe preferred mode is mono (1 channels).
DSP_CH_STEREOThe preferred mode is stereo (2 channels).
DSP_CH_MULTIThe preferred mode is multichannels (3 or more channels).

The value of this field doesn't mean that the device can be used only with this channel configuration. All the other configurations are definitely possible. The min_channels and max_channels information returned by SNDCTL_AUDIOINFO tells exactly how many channels the device can support natively.

The application can use this field if it needs to decide what is the default mode to be used with the device. The end user must have a way to override this decision.

Audio device capabilities like DSP_CH_MASK can be checked using the SNDCTL_AUDIOINFO or SNDCTL_DSP_GETCAPS ioctl calls.

Copyright (C) 4Front Technologies, 2007. All rights reserved.
Back to index OSS web site