Ioctl Requests                                  audiosupport(7I)



NAME
     audiosupport - audio driver support routines and interface

SYNOPSIS
     #include 


DESCRIPTION
     The audio support  module supports audio  drivers  that  use
     the  new audio driver  architecture. It also provides a lim-
     ited number of ioctl(2) functions for  application  program-
     mers.

DATA STRUCTURES
     The following data structures are defined to manage the dif-
     ferent audio device types and  channels.

  Device Types
     The following enumeration lists a number of  generic  device
     types.

       typedef enum {
            UNDEFINED, AUDIO, AUDIOCTL, USER1, USER2, USER3
       } audiodevicetypee;



     Currently, the Solaris audio mixer implements only the AUDIO
     and  AUDIOCTL  audio  device types. See the mixer(7I) manual
     page for details. The USER1, USER2 and  USER3  device  types
     allow  third  parties  to write audio personality modules of
     their own.

  Channel Structure
     This structure is used to get and set state  information  on
     individual channels.

       struct audiochannel {
            pidt               pid;           /* application's process ID */
            uintt              chnumber;     /* device channel */
            audiodevicetypee devtype;      /* device type */
            uintt              infosize;     /* size of channel's */
                                               /* info structure */
            void                *info;         /* channel state information */
       ;
       typedef struct audiochannel audiochannelt;



     The chnumber must specify the specific  channel  number  to
     get  or  set. When the ioctl() returns, the pid contains the
     process ID of the process that has  that  channel  open  and



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Ioctl Requests                                  audiosupport(7I)



     devtype  will  contain the device type. If pid is 0 (zero),
     then the channel is not open. The pointer *info  must  point
     to  a  buffer  large  enough  to hold whatever audio device-
     related state structure that  may  be  returned.  Currently,
     only   the  audioinfot  structure  is  returned.  See  the
     audio(7I) and mixer(7I) man pages for more information.

IOCTLS
     The audio support  driver provides the following ioctls():

     AUDIOGETCHNUMBER     This  ioctl()  returns  the  channel
                             number   pointed   to  by  the  file
                             descriptor. It is  returned  in  the
                             integer pointer of the ioctl() argu-
                             ment.


     AUDIOGETCHTYPE       This ioctl()  returns  the  type  of
                             channel  the process has open. It is
                             returned in the  audiodevicetypee
                             enumeration  pointer  of the ioctl()
                             argument.


     AUDIOGETNUMCHS     This ioctl()  returns  the  number  of
                           channels  the  device  supports. It is
                           returned in the integer pointer of the
                           ioctl() argument.


MACROS
     The following macro can be used to  initialize  data  struc-
     tures.   The   established  convention  is  that  the  state
     corresponding to a field set to -1 will not be modified.

       AUDIOINIT(I, S)



     Where I is a pointer to an info structure and S is the  size
     of that structure.


     The following code segment  demonstrates  how  to  use  this
     macro:

       audioinfot    info;

       AUDIOINIT(&info, sizeof(info));
       info.play.port = AUDIOHEADPHONE;
       err = ioctl(audiofd, AUDIOSETINFO, &info);




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Ioctl Requests                                  audiosupport(7I)



ERORS
     EINVAL     The ioctl() is invalid for this file  descriptor.
                The audiochannelt structure's info pointer does
                not point to a buffer, or the chnumber is bad.


     ENOMEM     The ioctl() failed due to lack of memory.


FILES
     /usr/share/audio/samples      Audio sample files


ATRIBUTES
     See attributes(5) for a description of the following  attri-
     butes:



     
     ATRIBUTE TYPE                ATRIBUTE VALUE              
     Architecture                  SPARC, x86                   
     Availability                  SUNWaudd, SUNWauddx, SUNWaudh
     Stability Level               Evolving                     
    


SEE ALSO
     ioctl(2), attributes(5), audio(7I), mixer(7I), streamio(7I)

FUTURE DIRECTIONS
     Over time, additional  audio  personality  modules  will  be
     added.  Audio  application  programmers  are  encouraged  to
     review this man page with each Solaris release for new audio
     personality modules.




















SunOS 5.11         Last change: 2 January 2002                  3