diff -aur slim-1.3.1.orig/switchuser.cpp slim-1.3.1/switchuser.cpp
--- slim-1.3.1.orig/switchuser.cpp	2008-09-26 02:54:15.000000000 +0200
+++ slim-1.3.1/switchuser.cpp	2009-07-20 15:23:06.105573161 +0200
@@ -9,6 +9,7 @@
    (at your option) any later version.
 */
 
+#include <cstdio>
 #include "switchuser.h"
 
 using namespace std;