+
+/*
+ * Error return codes from gethostbyname() and gethostbyaddr()
+ */
+
+extern int h_errno;
+
+#define HOST_NOT_FOUND 1 /* Authoritive Answer Host not found */
+#define TRY_AGAIN 2 /* Non-Authoritive Host not found, or SERVERFAIL */
+#define NO_RECOVERY 3 /* Non recoverable errors, FORMERR, REFUSED, NOTIMP */
+#define NO_ADDRESS 4 /* Valid host name, no address, look for MX record */