diff --git a/libc/fmtlock.c b/libc/fmtlock.c
index 5c7afbc..60bce97 100644
--- a/libc/fmtlock.c
+++ b/libc/fmtlock.c
@@ -1,27 +1,16 @@
-/*
- * The authors of this software are Rob Pike and Ken Thompson.
- *              Copyright (c) 2002 by Lucent Technologies.
- * Permission to use, copy, modify, and distribute this software for any
- * purpose without fee is hereby granted, provided that this entire notice
- * is included in all copies of any software which is or includes a copy
- * or modification of this software and in all copies of the supporting
- * documentation for such software.
- * THIS SOFTWARE IS BEING PROVIDED "AS IS", WITHOUT ANY EXPRESS OR IMPLIED
- * WARRANTY.  IN PARTICULAR, NEITHER THE AUTHORS NOR LUCENT TECHNOLOGIES MAKE
- * ANY REPRESENTATION OR WARRANTY OF ANY KIND CONCERNING THE MERCHANTABILITY
- * OF THIS SOFTWARE OR ITS FITNESS FOR ANY PARTICULAR PURPOSE.
- */
-#include <stdarg.h>
-#include "plan9.h"
-#include "fmt.h"
-#include "fmtdef.h"
+#include <u.h>
+#include <libc.h>
+
+static Lock fmtl;
 
 void
 __fmtlock(void)
 {
+	lock(&fmtl);
 }
 
 void
 __fmtunlock(void)
 {
+	unlock(&fmtl);
 }