The midiInUnprepareHeader function cleans up the preparation performed by the midiInPrepareHeader function.
MMRESULT midiInUnprepareHeader( HMIDIIN hmi, LPMIDIHDR pmh, UINT cbmh );
Handle to the MIDI input device.
Pointer to a MIDIHDR structure identifying the buffer to be cleaned up.
Size of the MIDIHDR structure.
Returns MMSYSERR_NOERROR if successful or an error otherwise. Possible error values include the following.
||The buffer pointed to by lpMidiInHdr is still in the queue.|
||The specified pointer or structure is invalid.|
||The specified device handle is invalid.|
This function is complementary to midiInPrepareHeader. You must use this function before freeing the buffer. After passing a buffer to the device driver by using the midiInAddBuffer function, you must wait until the driver is finished with the buffer before using midiInUnprepareHeader. Unpreparing a buffer that has not been prepared has no effect, and the function returns MMSYSERR_NOERROR.
|Minimum supported client||Windows 2000 Professional [desktop apps only]|
|Minimum supported server||Windows 2000 Server [desktop apps only]|
|Header||mmeapi.h (include Windows.h)|