waveInUnprepareHeader function (mmeapi.h)

The waveInUnprepareHeader function cleans up the preparation performed by the waveInPrepareHeader function. This function must be called after the device driver fills a buffer and returns it to the application. You must call this function before freeing the buffer.

Syntax

MMRESULT waveInUnprepareHeader(
  HWAVEIN   hwi,
  LPWAVEHDR pwh,
  UINT      cbwh
);

Parameters

hwi

Handle to the waveform-audio input device.

pwh

Pointer to a WAVEHDR structure identifying the buffer to be cleaned up.

cbwh

Size, in bytes, of the WAVEHDR structure.

Return value

Returns MMSYSERR_NOERROR if successful or an error otherwise. Possible error values include the following.

Remarks

This function complements the waveInPrepareHeader function.

You must call this function before freeing the buffer. After passing a buffer to the device driver with the waveInAddBuffer function, you must wait until the driver is finished with the buffer before calling waveInUnprepareHeader. Unpreparing a buffer that has not been prepared has no effect, and the function returns zero.

Requirements

See also

Waveform Audio

Waveform Functions