diff --git a/config.h b/config.h
index bd1dac1..76c7514 100644
--- a/config.h
+++ b/config.h
@@ -325,6 +325,11 @@ const char *gai_strerror(int);
 #define AI_CANONNAME    0x0002  /* Request for canonical name.  */
 #endif
 
+#ifndef AI_ADDRCONFIG
+#define AI_ADDRCONFIG   0x0020  /* Use configuration of this host to choose
+                                   returned address type..  */
+#endif
+
 #ifndef EAI_NONAME
 #define EAI_NONAME      -2    /* NAME or SERVICE is unknown.  */
 #endif
@@ -335,15 +340,16 @@ const char *gai_strerror(int);
 #define EAI_MEMORY      -10   /* Memory allocation failure.  */
 #endif
 #ifndef EAI_SYSTEM
-#define EAI_SYSTEM      -11   /* System error returned in rrno'.  */
+#define EAI_SYSTEM      -11   /* System error returned in `errno'.  */
 #endif
 #endif
 
+#ifndef INET6_ADDRSTRLEN
+#define INET6_ADDRSTRLEN 46
+#endif
+
 #ifndef HAVE_INET_NTOP
 const char *inet_ntop(int, const void *, char *, socklen_t);
-#ifndef INET6_ADDRSTRLEN
-#define INET6_ADDRSTRLEN 48
-#endif
 #endif
 
 /* tftp-hpa version and configuration strings */