ACMDM_STREAM_RESET

This message requests an ACM driver to stop conversion operations for the specified stream.

Parameters

dwDriverID

Specifies a driver instance identifier. The driver returns this value in response to the ACM_Open function.

hDriver

Handle to a driver.

uMsg

Specifies this message.

lParam1

Pointer to an ACMDRVSTREAMINSTANCE structure.

lParam2

Contains the fdwReset parameter of the acmStreamReset function.

Return Values

MMSYSERR_NOERROR indicates success. Otherwise, the driver returns one of the MMSYSERR error values declared in the Mmsystem.h header file or one of the ACMERR error values declared in the Msacm.h header file.

Remarks

The ACM (Waveapi.dll) sends the ACMDM_STREAM_RESET message by calling the ACM driver’s ACM_IOControl entry point through the DeviceIoControl function. The ACM sends this message when an application calls the acmStreamReset function.

Only asynchronous drivers receive this message. If a client calls acmStreamReset for a synchronous driver, the ACM returns MMSYSERR_NOERROR without calling the driver.

When an asynchronous driver receives this message, it sets the ACMSTREAMHEADER_STATUSF_DONE flag and clears the ACMSTREAMHEADER_STATUSF_INQUEUE flag in every ACMDRVSTREAMHEADER structure contained in its conversion queue.

For more information about stream conversions, see the Windows NT DDK.