dns_name_fullcompare
namereln = dns_name_fullcompare(name, domain,
dns_name_fullcompare(const dns_name_t *name1, const dns_name_t *name2,
(void)dns_name_fullcompare(name1, name2, &order, &nlabels);
namereln = dns_name_fullcompare(name1, name2, &order, &nlabels);