rrset_data_delete
ub_rrset_key_delete, rrset_data_delete, alloc);
void rrset_data_delete(void* data, void* userdata);
else if(fptr == &rrset_data_delete) return 1;
ub_rrset_key_delete, rrset_data_delete, alloc);
void rrset_data_delete(void* data, void* userdata);
else if(fptr == &rrset_data_delete) return 1;