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Open Sound System
OSS 4.x User's Guide

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sndstat - Open Sound System status device

/dev/sndstat is a text formatted device special file that returns information about available (OSS) sound devices. This device file is obsolete and the ossinfo utility should be used instead.

Notice that the device numbering used in this file is different that the official numbering used by ossinfo and some other utilities. /dev/sndstat uses device numbers that match the "legacy" /dev/dspN, /dev/midiN and /dev/mixerN device files.

Application programs should not use /dev/sndstat to obtain information about the sound devices. The format of this file may change in the future and /dev/sndstat may even be removed from OSS in distant future. OSS 4.0 and later has an ioctl interface for getting detailed and reliable information about the devices.

AUDIO USAGE HISTORY

/dev/sndstat reports some history information about previously run audio applications. This section is a debugging aid for application developers and it will be moved to the ossinfo program in the future.

For example:

History:
/dev/oss/hdaudio0/pcm0.10: pid 6326 cmd 'error_test' OUT Play events:01009:2 Rec events:01002:0
/dev/oss/hdaudio0/pcm0.10: pid 6329 cmd 'mpg123' OUT
/dev/oss/hdaudio0/pcm0.10: pid 6329 cmd 'mpg123' OUT
/dev/oss/hdaudio0/pcm0.10: pid 6329 cmd 'mpg123' OUT

Each line will show the the device name, PID and name of the application (if known) and access mode (IN and/or OUT). There may also be additional info about buffer underruns/overruns and other recording and playback related events.

Each Play and rec events consist of 5-6 digit event code and a parameter separated by a colon. A list of defined event codes and their explanations can be found from http://manuals.opensound.com/developer/oss_error_codes.html. Purpose of these events is to inform application developers by potential problems in their code.

COMPATIBILITY

/dev/sndstat has been available in all OSS versions. However in OSS 4.0 and later this device file should only be used by applications written for earlier OSS versions.

OPTIONS

None

PROGRAMMING INFORMATION

Some applications use /dev/sndstat to find the audio devices available in the system. This method is no longer recommended. Applications should use the SNDCTL_AUDIOINFO ioctl call to find the devices.

SEE ALSO

FILES

/dev/sndstat

AUTHOR

4Front Technologies



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