+#if !HAVE_DECL_GETNAMEINFO
+/* Convert socket address to printable node and service names.
+ For more details, see the POSIX:2001 specification
+ <http://www.opengroup.org/susv3xsh/getnameinfo.html>. */
+extern int getnameinfo(const struct sockaddr *restrict sa, socklen_t salen,
+ char *restrict node, socklen_t nodelen,
+ char *restrict service, socklen_t servicelen,
+ int flags);
+
+#endif
+
+/* Possible flags for getnameinfo. */
+#ifndef NI_NUMERICHOST
+# define NI_NUMERICHOST 1
+#endif
+#ifndef NI_NUMERICSERV
+# define NI_NUMERICSERV 2
+#endif