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       dsp - Open Sound System audio devices


       /dev/dsp  is  the default audio device in the system. It's connected to
       the  main  speakers  and  the  primary  recording   source   (such   as
       microphone). 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.


       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.


       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.


       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

       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.


       See the  Audio  Programming  section  of  the  OSS  Programmer's  Guide
       (DSP(2)) for more info.




       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.


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