diff -Nur slim-1.3.1.orig/switchuser.cpp slim-1.3.1/switchuser.cpp
--- slim-1.3.1.orig/switchuser.cpp	2008-09-25 19:54:15.000000000 -0500
+++ slim-1.3.1/switchuser.cpp	2009-11-09 12:05:40.694438191 -0600
@@ -9,6 +9,7 @@
    (at your option) any later version.
 */
 
+#include <stdio.h>
 #include "switchuser.h"
 
 using namespace std;