From 7ae9bb1196aa3c5c56d12da09d465b63106713f0 Mon Sep 17 00:00:00 2001
From: Simon Lieb <simon@tibu.fr>
Date: Thu, 8 Aug 2013 21:03:11 +0200
Subject: [PATCH] Write usage() message on stderr.

---
 slow.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/slow.c b/slow.c
index 32a4b9f..c61c0a3 100644
--- a/slow.c
+++ b/slow.c
@@ -8,7 +8,7 @@
 char *argv0;
 
 void usage() {
-	printf("usage: %s [-t usec] [-F]\n", argv0);
+	fprintf(stderr, "usage: %s [-t usec] [-F]\n", argv0);
 	exit(EXIT_FAILURE);
 }