$NetBSD: patch-ah,v 1.2 2007/07/18 11:25:21 tnn Exp $

--- src/df.c.orig	2007-03-18 22:36:43.000000000 +0100
+++ src/df.c
@@ -943,8 +943,10 @@ main (int argc, char **argv)
 	     _("%scannot read table of mounted file systems"), warning);
     }
 
+#if HAVE_SYNC
   if (require_sync)
     sync ();
+#endif
 
   if (optind < argc)
     {
