Callbacks in BACI: device.property.get(CB)

interface CB<type> : CB {
oneway void execute(in <type> value, in Completion c, in CBDescOut desc);
oneway void cb_done(in <type> value, in Completion c, in CBDescOut desc);
};

interface CB<event_set_name> : CB {
oneway void <event_1_name>(..., in CBDescOut desc);
oneway void <event_2_name>(..., in CBDescOut desc);
...
}
...
void subscribe_<event_set_name>(in CB<event_set_name> cb, in CBDescIn desc);
void unsubscribe_<event_set_name>(in CB<event_set_name> cb);