1. ► A cbValueChangeCallback is a one-time callback and must be re-registered.
2. ► A checker will typically register itself at cbNextSim time.
3. ► Callbacks are functions which called by the simulation kernel at appropriate points during
4. ► In s_cb_data, the user_data field cannot be NULL.
5. ► In s_cb_data, the cb_rtn field is used to provide the function pointer which will be called when the callback event happens.
6. ► In s_cb_data, the obj field is used to point to the handle on which the callback is registered.
7. ► In C++ callbacks are implemented using object pointers.
8. ► cbReadWriteSync callbacks are called before cbReadOnlySynch callbacks.
9. ► A cbValueChange callback can be directly registered from vlog_startup_routines called
10. ► Callbacks can only be implemented using function pointers in any language.