ACMDM_STREAM_CLOSE

See also ACMDM_STREAM_CONVERT, ACMDM_STREAM_OPEN, ACMDM_STREAM_PREPARE, ACMDM_STREAM_RESET, ACMDM_STREAM_SIZE, ACMDM_STREAM_UNPREPARE, ACMDRVOPENDESC, ACMDRVSTREAMHEADER, ACMDRVSTREAMINSTANCE, ACMDRVSTREAMSIZE

lParam1 = (LPARAM) pacmDSI  // see below
lParam2 = reserved          // should be ignored

Sent to an Audio Compression Manager (ACM) driver to close a previously opened conversion stream. This message is usually sent to an ACM driver in response to an acmStreamClose call.

• Return MMSYSERR_NOERROR if the operation is successful or ACMERR_BUSY if the conversion stream is in a state that does not allow the stream to be closed. For example, this error should be returned if a driver is performing asynchronous conversions for the stream and pending buffers are in the queue. This error should only be possible for asynchronous drivers.

lParam1

Address of the ACMDRVSTREAMINSTANCE structure for the conversion stream that is to be closed.

An ACM driver must support this message if it supports the ACMDM_STREAM_OPEN message. Before calling the driver, the lParam1 parameter of the ACMDM_STREAM_CLOSE message will be validated. This parameter will contain a valid pointer to an ACMDRVSTREAMINSTANCE structure with the same information as the corresponding ACMDM_STREAM_OPEN message. The driver does not need to check for this condition.