--- ./Arena/Implementation/icon.c.org	Thu Mar 21 07:28:53 1996
+++ ./Arena/Implementation/icon.c	Tue Apr 30 00:22:54 1996
@@ -46,7 +46,9 @@
 #if defined __QNX__ || (defined(sco) && !defined(sco_os5))
 #define index strchr
 #else
+#if !defined(index)
 extern char *index();
+#endif
 #endif
 
 static char basis_64[] =
