AGetGain(3X)

NAME

AGetGain − get play volume or record gain of specified transaction

SYNOPSIS

#include <Alib.h> void
AGetGain (

Audio ∗ audio,

ATransID xid,

AGainDB ∗ gain_return

long ∗ status_return );

DESCRIPTION

AGetGain() returns the play volume or record gain of the transaction specified in xid.

audio specifies the Audio structure associated with this connection.

xid specifies the transaction ID.

gain_return receives the returned gain value or record gain (decimal value).

status_return receives the returned status of the operation, unless this parameter is passed in as a NULL pointer. If status_return is set to NULL, Alib will do the error handling.

STRUCTURES

The following is defined in /opt/audio/include/Alib.h:

typedef long ATransID; /* Type for transaction ID. */

ERRORS

If status_return is not set to NULL, it can return one of the following values:

0 AENoError No error - the call completed successfully.

2 AEBadAudio The audio structure is invalid. A pointer to a valid audio structure may be missing (use AOpenAudio() to get a valid pointer).

15 AEBadTransactionID The xid parameter does not identify a valid transaction ID.

EXAMPLE

The following example gets the gain for the xid transaction and sets up status to receive an error status.

Audio ∗ audio; /∗ audio connection ∗/

TransID xid; /∗ transaction ID ∗/

AGainDB gain_return; /∗ gain return ∗/

long status; /∗ error status ∗/
.
.
.

/∗ get gain for xid returned by prior call ∗/

AGetGain(audio, xid, &gain_return, &status);

NOTE

In order to ensure that the compiler finds the Audio Library (libAlib.sl) and the Alib.h header file, you must add the following switches:

-L /opt/audio/lib
-I/opt/audio/include

DEPENDENCIES

This function belongs to the Audio Library of functions that manage connections to an audio server. The audio server must run on a system that has audio hardware. To find out whether or not your system has audio hardware, refer to Using the Audio Developer’s Kit or the online help for the Audio control panel. For information about the audio capabilities of a particular system use the online example audioinfo.c.

AUTHOR

AGetGain() was developed by HP.

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