Sent to a MIDI input device driver to deallocate a specified device.
MMSYSERR_NOTENABLED | The driver failed to load or initialize. |
MIDIERR_STILLPLAYING | There are still buffers in the queue. |
If there are input buffers that have been received with the MIDM_ADDBUFFER message and haven't been returned to the application, the driver should fail the close operation by returning MIDIERR_STILLPLAYING. If the close operation is successful, the driver should use the DriverCallback function to send the client a MIM_CLOSE message.
MIDM_OPEN