waveInUnprepareHeader
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4/8/2010
This function cleans up the preparation performed by waveInPrepareHeader. The function must be called after the device driver fills a data buffer and returns it to the application. You must call this function before freeing the data 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
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 |
Buffer pointed to by the pwh parameter is still in the queue. |
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
| Header | mmsystem.h |
| Library | coredll.lib |
| Windows Embedded CE | Windows CE 2.0 and later |
| Windows Mobile | Windows Mobile Version 5.0 and later |