diff --git a/src/test.c b/src/test.c
index 333850dde..3be1cb6ac 100644
--- a/src/test.c
+++ b/src/test.c
@@ -67,7 +67,7 @@ extern int errno;
 #endif /* !STREQ */
 
 #if !defined (member)
-#  define member(c, s) ((c) ? (index ((s), (c)) ? 1 : 0) : 0)
+#  define member(c, s) ((c) ? (strchr ((s), (c)) ? 1 : 0) : 0)
 #endif /* !member */
 
 extern gid_t getgid (), getegid ();