A module may also want to react to certain Simics events. This may both be events related to the simulated machine, like processor exceptions or control register writes, and other kinds of events, like Simics stopping the simulation and returning to the command line. In Simics such events are referred to as haps. To react to a hap a module can register a callback function to the hap. This callback function will then be called every time the hap occurs. Again, a complete list of all haps, descriptions of what parameters the callback functions should take and all functions used to register callbacks and manipulate haps can be found in the Simics Reference Manual.
DML has no built-in features for hap, so you should refer to the C/C++ and Python explanation in section 6.8.