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dsp(7) [debian man page]

7(16 December 2012)													       7(16 December 2012)

NAME
dsp - Open Sound System audio devices DESCRIPTION
/dev/dsp is the default audio device in the system. It's connected to the main speakers and the primary recording source (such as micro- phone). The system administrator can set /dev/dsp to be a symbolic link to the desired default device. The ossinfo utility can be used to list the available audio devices in the system. /dev/dsp_mmap, /dev/dsp_ac3, /dev/dsp_multich and /dev/dsp_spdifout are default audio devices for specific applications such as games or media (DVD) players. DIRECT ACCESS AUDIO DEVICE FILES
OSS 4.0 (and later) will create audio devices under /dev/oss/<device> directory. For example /dev/oss/sblive0/pcm0 is the first audio device that belongs to the first Sound Blaster Live! or Audigy card in the system. These direct devices are used when an application needs to access specific audio device (instead of the default one). You can use the ossinfo(1) utility with the -a option to get a list of the available audio devices in the system. LEGACY AUDIO DEVICE FILES
Traditionally OSS has created device files like /dev/dsp0 to /dev/dspN for each audio device in the system. OSS 4.0 still supports this legacy naming. These files are symbolic links to the actual device files located under /dev/oss. The ossdevlinks(8) utility is used to manage these links and it will be automatically invoked when OSS is started. COMPATIBILITY
o The /dev/dsp (default() audio device file will be supported by all OSS implementations and versions. o The special purpose audio default devices (such as /dev/dsp_mmap) are only supported by OSS 4.0 and later. o The legacy audio device files (such as /dev/dsp1) are supported by all OSS versions and implementations. o New style audio device files (under /dev/oss) are only supported by OSS 4.0 and later. However some independent OSS implementations may only support the legacy naming even they are otherwise OSS 4.0 compatible. o /dev/dsp0 doesn't exist in all Linux systems which use /dev/dsp for the same purpose. In such systems /dev/dsp points to the first audio device and /dev/dsp1 to the second. PROGRAMMING INFORMATION
See the Audio Programming section of the OSS Programmer's Guide (DSP(2)) for more info. OPTIONS
None FILES
o /dev/dsp Default audio device o /dev/dsp_mmap Default audio device for applications using mmap(2) o /dev/dsp_ac3 Default audio device for applications sending Dolby Digital (AC3) audio to an external receiver. o /dev/dsp_multich Default multichannel (4.0-7.1) audio output device o /dev/dsp_spdifout Default digital audio (S/PDIF) output device o /dev/oss/<driver>/pcmN Direct access device files for individual audio devices. o /dev/dsp0 to /dev/dspN Legacy style direct access audio device files. AUTHOR
4Front Technologies OSS Devices 7(16 December 2012)

Check Out this Related Man Page

mixerctl(1)							   User Commands						       mixerctl(1)

NAME
mixerctl - audio mixer control command line application SYNOPSIS
/usr/sbin/mixerctl [-a | -d dev] [-iv] [-e | -o] DESCRIPTION
Some audio devices support the audio mixer functionality. See mixer(7I) for a complete description of the audio mixer. The mixerctl command is used to control the mode of the audio mixer and to get information about the audio mixer and the audio device. See audio(7I) for details. OPTIONS
The following options are supported. If none are specified, option -i is assumed: -a The command applies to all audio devices. -d dev The dev argument specifies an alternate audio control device for the command to use. -e Enables the audio mixer function if the audio device supports it. If supported, the audio mixer may be enabled at any time. The command silently ignores the enable option if the audio mixer is already enabled. -i Prints the audio device type information for the device and indicates whether the audio device uses the audio mixer. If the device does use the audio mixer, this option displays the audio mixer's mode. -o Turns off the audio mixer function if the audio device supports it. If supported, the audio mixer may be turned off if only one process has the device opened with the O_RDWR flag, or, if two different processes have the device opened, one with the O_RDONLY flag and the other with the O_WRONLY flag. (See open(2).) The command silently ignores the disable option if the audio mixer function is already disabled. -v Verbose mode. Prints the audio_info_t structure for the device, along with the device type information. This option implies the -i option. ENVIRONMENT VARIABLES
AUDIODEV If the -d and -a options are not specified, the AUDIODEV environment variable is consulted. If set, AUDIODEV will contain the full path name of the user's default audio device. The default audio device will be converted into a control device, and then used. If the AUDIODEV variable is not set, /dev/audioctl is used. FILES
/dev/audioctl /dev/sound/{0...n}ctl ATTRIBUTES
See attributes(5) for descriptions of the following attributes: +-----------------------------+-----------------------------+ | ATTRIBUTE TYPE | ATTRIBUTE VALUE | +-----------------------------+-----------------------------+ |Architecture |SPARC, x86 | +-----------------------------+-----------------------------+ |Availability |SUNWauda | +-----------------------------+-----------------------------+ |Stability Level |Evolving | +-----------------------------+-----------------------------+ SEE ALSO
audioconvert(1), audioplay(1), audiorecord(1), open(2), attributes(5), usb_ac(7D), audio(7I), audio_support(7I), mixer(7I) SunOS 5.10 12 Mar 2001 mixerctl(1)
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