Use this function to query the current event filter.
SDL_bool SDL_GetEventFilter(SDL_EventFilter* filter, void** userdata)
the current callback function will be stored here; see Remarks for details
the pointer that is passed to the current event filter will be stored here
Returns SDL_TRUE on success or SDL_FALSE if there is no event filter set.
You can add your code example here
This function can be used to "chain" filters, by saving the existing filter before replacing it with a function that will call that saved filter.