waveOutUnprepareHeader (Windows CE 5.0)
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.
MMRESULT waveOutUnprepareHeader(HWAVEOUThwo,LPWAVEHDRpwh,UINTcbwh );
Parameters
- hwo
Handle to the waveform-audio output device. - pwh
Pointer to a WAVEHDR structure identifying the data block to be cleaned up. - cbwh
Size, in bytes, of the WAVEHDR structure.
Return Values
One of the values described in the following table is returned.
| Value | Description |
|---|---|
| MMSYSERR_NOERROR | Success. |
| MMSYSERR_INVALHANDLE | Specified device handle is invalid. |
| MMSYSERR_NODRIVER | No device driver is present. |
| MMSYSERR_NOMEM | Unable to allocate or lock memory. |
| WAVERR_STILLPLAYING | Data block pointed to by the pwh parameter is still in the queue. |
Remarks
This function complements waveOutPrepareHeader. You must call this function before freeing the buffer. After passing a buffer to the device driver with the waveOutWrite function, 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.
Requirements
OS Versions: Windows CE 2.0 and later.
Header: Mmsystem.h.
Link Library: Coredll.lib.
See Also
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