AuElementNotifyEvent(3)AuElementNotifyEvent(3)NameAuElementNotifyEvent - 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 AuEventType‐
ElementNotify.
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 AuElemen‐
tAll to indicate the flow.
kind The kind of notify event. This will be one of these con‐
stants: AuElementNotifyKindLowWater, AuElementNotifyKindHigh‐
Water, or AuElementNotifyKindState.
prev_state
The previous state of the element indexed by element_num.
This will be one of these constants: AuStateStop, AuStateS‐
tart, or AuStatePause.
cur_state The current state of the element indexed by element_num.
This will be one of these constants: AuStateStop, AuStateS‐
tart, 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 AuElementNotifyKind‐
LowWater, 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.
See Also
AuAnyEvent, AuErrorEvent, AuGrabNotifyEvent, AuMakeSendNotifyAction,
AuMonitorNotifyEvent.
audiolib - Network Audio System C Language Interface
audiolib - events 1.9.4 AuElementNotifyEvent(3)
