Events.
* This is an union passed to the callback, that allows the frontend to know
* which type of event was triggered (via type). It is then possible to
* typecast the pointer to the right structure, or use the union field, in order
* to access event-specific data.
Events. * This is an union passed to the callback, that allows the frontend to know * which type of event was triggered (via type). It is then possible to * typecast the pointer to the right structure, or use the union field, in order * to access event-specific data.