+/* We define a few private types for special DNS lookups:
+
+ . T_ZNS gets the nameservers of the enclosing zone of a domain
+
+ . T_MXH gets the MX hostnames only (without their priorities)
+
+ . T_CSA gets the domain's Client SMTP Authorization SRV record
+
+*/
+
+#define T_ZNS (-1)
+#define T_MXH (-2)
+#define T_CSA (-3)
+