Since we might end up using the bulk type event logger in more places going forward, I would do something similar as we done with other event pipe types, represent them as a struct and potentially add getter/setters init/fini and alloc/free (if you need heap allocation). Since this type is currently only used in Mono's EP implementation you should define this type within Mono specific EP sources, like ep-rt-mono.h/ep-rt-mono.c.