APauseAudio(3X)

NAME

APauseAudio − pause the specified audio transaction

SYNOPSIS

#include <Alib.h> void
APauseAudio (

Audio ∗ audio,

ATransID xid,

ATransStatus ∗ trans_status_return,

long ∗ status_return );

DESCRIPTION

APauseAudio() pauses the transaction specified in xid. To continue with the operation, call AResumeAudio().

While one transaction is paused, another transaction can play or record.

To stop the transaction so that it cannot be resumed, call AStopAudio().

audio specifies the Audio structure associated with this connection.

xid specifies the transaction ID.

To use APauseAudio() on a series of linked transactions, specify the first transaction in the linked list. The pause affects the current transaction. A call to AResumeAudio() resumes the transaction and continues through the linked list.

trans_status_return receives the transaction status value. Setting this argument to NULL prevents the data from being collected and returned, which may enhance performance.

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 are defined in /opt/audio/include/Alib.h:

typedef long      ATransID; /* Type for transaction ID. */
/* Enumerated type for transaction state. */
typedef enum _ATransState {
    ATSUnknownTransID,
    ATSPlaying,
    ATSRecording,
    ATSLooping,
    ATSPaused,
    ATSStopped,
    ATSLoopStopped,
    ATSPending
} ATransState;
/* Enumerated type and structure for time specification.
*/
typedef enum _ATimeType {
    ATTSamples,
    ATTMilliSeconds,
    ATTFullLength
} ATimeType;
typedef struct _ATime {
    ATimeType                   type;
    union {
        unsigned long           samples;
        unsigned long           milliseconds;
    } u;
} ATime;
/* Structure for transaction status. */
typedef struct _ATransStatus {
    ATransState   state; /* State of transaction when audio
                            server returned the information. */
    ATime         time; /* Number of milliseconds or samples
                            from the beginning of the audio
                            data when the audio server
                            returned the information.        */
} ATransStatus;

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.

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

APauseAudio() was developed by HP.

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