--- expect-5.28/exp_strf.c	Fri May  3 22:01:25 1996
+++ expect-5.28.pld/exp_strf.c	Sun Jan 31 20:18:39 1999
@@ -97,8 +97,9 @@
 static int weeknumber();
 adddecl(static int iso8601wknum();)
 #else
-
+#if !((__GLIBC__ == 2) && (__GLIBC_MINOR__ >= 1))
 extern char *strchr(const char *str, int ch);
+#endif /* GNU libc-2.1 */
 extern char *getenv(const char *v);
 static int weeknumber(const struct tm *timeptr, int firstweekday);
 adddecl(static int iso8601wknum(const struct tm *timeptr);)