time support: For portability, also include <time.h>
diff --git a/include/config.h.in b/include/config.h.in
index 7621126..2fe8965 100644
--- a/include/config.h.in
+++ b/include/config.h.in
@@ -78,6 +78,9 @@
 /* Define to 1 if you have the <sys/types.h> header file. */
 #undef HAVE_SYS_TYPES_H
 
+/* Define to 1 if you have the <time.h> header file. */
+#undef HAVE_TIME_H
+
 /* Define to 1 if you have the <unistd.h> header file. */
 #undef HAVE_UNISTD_H