audio_support(7I)						  Ioctl Requests						 audio_support(7I)

NAME

       audio_support - audio driver support routines and interface

SYNOPSIS

       #include <sys/audio.h>

DESCRIPTION

       The audio support  module supports audio drivers that use the new audio driver  architecture. It also provides a limited number of ioctl(2)
       functions for application programmers.

DATA STRUCTURES

       The following data structures are defined to manage the different 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
	      } audio_device_type_e;

       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 audio_channel {
		   pid_t			 pid;		/* application's process ID */
		   uint_t			 ch_number;	/* device channel */
		   audio_device_type_e dev_type;      /* device type */
		   uint_t			 info_size;	/* size of channel's */
								     /* info structure */
		   void 		    *info;		/* channel state information */
	      ;
	      typedef struct audio_channel audio_channel_t;

       The  ch_number  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 dev_type 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
       audio_info_t structure is returned.  See the audio(7I) and mixer(7I) man pages for more information.

IOCTLS

       The audio support  driver provides the following ioctls():

       AUDIO_GET_CH_NUMBER	       This ioctl() returns the channel number pointed to by the file descriptor. It is returned  in  the  integer
				       pointer of the ioctl() argument.

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

       AUDIO_GET_NUM_CHS	       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 structures. The established convention is that the state corresponding to a field set to
       -1 will not be modified.

	      AUDIO_INIT(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:

	      audio_info_t    info;

	      AUDIO_INIT(&info, sizeof(info));
	      info.play.port = AUDIO_HEADPHONE;
	      err = ioctl(audio_fd, AUDIO_SETINFO, &info);

ERRORS

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

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

FILES

       /usr/share/audio/samples

	    Audio sample files

ATTRIBUTES

       See attributes(5) for a description of the following attributes:

       +-----------------------------+------------------------------+
       |      ATTRIBUTE TYPE	     |	     ATTRIBUTE 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 5.10							  2 January 2002						 audio_support(7I)