The following code illustrates how to close a device context.

  ULONG mciDriverEntry (PINSTANCE pInst,
                        USHORT    usMessage,
                        ULONG     ulParam1,
                        ULONG     ulParam2,
                        USHORT    usUserParam)

{
  switch  (usMessage)  {
     case MCI_DEVICESETTINGS:
       return(InsertPage  ((PMCI_DEVICE_SETTINGS_PARMS) ulParam2));
}
}