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AcxRtStreamNotifyPacketComplete function (acxstreams.h)

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The driver calls AcxRtStreamNotifyPacketComplete when a packet has completed. The packet completion time and the 0-based Packet index are included to improve client performance. The ACX framework will set any notification events associated with the stream.

Syntax

NTSTATUS AcxRtStreamNotifyPacketComplete(
  ACXSTREAM Stream,
  ULONGLONG CompletedPacket,
  ULONGLONG QPCCompletion
);

Parameters

Stream

An existing ACXSTREAM Object. An ACXSTREAM object represents an audio stream created by a circuit. The stream is composed of a list of elements created based on the parent circuit's elements.

CompletedPacket

A 0-based Packet index indicating the packet that was just completed.

QPCCompletion

The packet completion time, as returned by KeQueryPerformanceCounter. This value should be as close as possible to the actual hardware completion (for example, the driver can call KeQueryPerformanceCounter from in its Interrupt Service Routine).

Return value

Returns STATUS_SUCCESS if the call was successful. Otherwise, it returns an appropriate error code. For more information, see Using NTSTATUS Values.

Remarks

AcxRtStreamNotifyPacketComplete must be called at DISPATCH_LEVEL or below.

Example

Example usage is shown below.

completedPacket = (ULONG)InterlockedIncrement((LONG*)&m_CurrentPacket) - 1;

InterlockedExchange64(&m_LastPacketStart.QuadPart, m_CurrentPacketStart.QuadPart);
InterlockedExchange64(&m_CurrentPacketStart.QuadPart, QPC.QuadPart);

// Tell ACX we've completed the packet.
(void)AcxRtStreamNotifyPacketComplete(m_Stream, completedPacket, QPC.QuadPart);

ACX requirements

Minimum ACX version: 1.0

For more information about ACX versions, see ACX version overview.

Requirements

Requirement Value
Header acxstreams.h
IRQL <= DISPATCH_LEVEL

See also