Name

AuElementNotifyEvent - element notify event structure

Structures

#include <audio/audiolib.h>

typedef union _AuEvent
{ . . . AuElementNotifyEvent auelementnotify; . . .
}AuEvent;

typedef struct _AuElementNotifyEvent
{ int type; AuUint32 serial; AuBool send_event; AuServer *server; AuTime time; AuFlowID flow; unsigned char element_num; unsigned char kind; unsigned char prev_state; unsigned char cur_state; unsigned char reason; AuUint32 num_bytes;
}AuElementNotifyEvent;

Members

type: The event type. ElementNotify events are type AuEventTypeElementNotify.
serial: The serial ID of the event expanded from the 16 bit value sent by the server.
send_event: AuTrue if the event came from a SendEvent protocol request.
server: The connection to the audio server that the event was read from.
time: The server time in milliseconds when the event was generated.
flow: The ID of the flow that caused the event.
element_num: The index of the element that caused the event or AuElementAll to indicate the flow.
kind: The kind of notify event. This will be one of these constants: AuElementNotifyKindLowWater, AuElementNotifyKindHighWater, or AuElementNotifyKindState.
prev_state: The previous state of the element indexed by element_num. This will be one of these constants: AuStateStop, AuStateStart, or AuStatePause.
cur_state: The current state of the element indexed by element_num. This will be one of these constants: AuStateStop, AuStateStart, or AuStatePause.
reason: The reason for the notify event. This will be one of these constants: AuReasonUser, AuReasonUnderrun, AuReasonOverrun, AuReasonEOF, AuReasonWatermark, or AuReasonHardware.
num_bytes: The number of bytes to send or receive. Only valid if the the element indexed by element_num is an ImportClient or ExportClient.

Description

ElementNotify events are sent to client applications to notify them of a watermark condition or state change. If kind is AuElementNotifyKindLowWater, the ImportClient element indexed by element_num in flow is ready to receive num_bytes of audio data from the client application. If kind is AuElementNotifyKindHighWater, the ExportClient element indexed by element_num in flow is ready to send num_bytes of audio data to the client application. If kind is AuElementNotifyKindState, the element indexed by element_num (or flow if element_num is AuElementAll) has made a state transition from prev_state to cur_state triggering the event. Reguardless of kind, prev_state and cur_state contain the old and new states and reason contains the reason for the event.

Name

Structures

Members

Description

See Also