WIDM_GETPOS

This message is used in an MMDRV_MESSAGE_PARAMS structure passed to the WAV_IOControl function to request a waveform input driver to return the current input position within a waveform. The input position is relative to the first recorded sample of the waveform.

Parameters

uDeviceId

Device identifier—0, 1, 2, and so on—for the target device.

uMsg

Specifies this message.

dwUser

Specifies a device instance identifier.

dwParam1

Specifies a pointer to an MMTIME structure.

dwParam2

Specifies the size, in bytes, of MMTIME.

Return Values

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

Remarks

The ACM sends this message by calling the audio driver’s WAV_IOControl entry point through the DeviceIoControl function.

The wType member of MMTIME indicates the time format requested by the client. If the driver cannot support the requested format, it returns the position in a format that it does support and changes the wType member accordingly.

The position is reset to 0 when the driver receives either of the messages WODM_OPEN or WODM_RESET.