WORD waveOutUnprepareHeader(hWaveOut, lpWaveOutHdr, wSize)
This function cleans up the preparation performed by waveOutPrepareHeader. The function must be called after the device driver is finished with a data block. You must call this function before freeing the data buffer.
HWAVEOUT hWaveOut
Specifies a handle to the waveform output device.
LPWAVEHDR lpWaveOutHdr
Specifies a pointer to a WAVEHDR structure identifying the data block to be cleaned up.
WORD wSize
Specifies the size of the WAVEHDR structure.
Returns zero if the function was successful. Otherwise, it returns an error number. Possible error returns are:
MMSYSERR_INVALHANDLE
Specified device handle is invalid.
WAVERR_STILLPLAYING
lpWaveOutHdr is still in the queue.
This function is the complementary function to waveOutPrepareHeader. You must
call this function before freeing the data buffer with GlobalFree. After passing a buffer
to the device driver with waveOutWrite, you must wait until the driver is finished with the buffer before calling waveOutUnprepareHeader.
Unpreparing a buffer that has not been prepared has no effect, and the function returns zero.
waveOutPrepareHeader