This message is used in an MMDRV_MESSAGE_PARAMS structure passed to the WAV_IOControl function to request a waveform input driver to stop recording and return all buffers in the input queue to the caller.
MMSYSERR_NOERROR indicates success. Otherwise, the driver returns one of the MMSYSERR or WAVERR error values declared in the Mmsystem.h header file.
The ACM sends this message by calling the audio driver’s WAV_IOControl entry point through the DeviceIoControl function.
For each buffer remaining in the driver’s input queue, the driver sets WHDR_DONE and clears WHDR_INQUEUE in the dwFlags member of the buffer’s WAVEHDR structure. It also sets the dwBytesRecorded member of the structure. Finally, the driver issues the callback message WIM_DATA for each buffer.