MPT_CONTEXT_CB_SHIFT
#define MPT_CBI(handle) (handle >> MPT_CONTEXT_CB_SHIFT)
#define MPT_CBI_TO_HID(cbi) ((cbi) << MPT_CONTEXT_CB_SHIFT)
(((x) >> MPT_CONTEXT_CB_SHIFT) & (MPT_NUM_REPLY_HANDLERS - 1))