diff --git a/key/goKey.h b/key/goKey.h
index 2c2021c..5153ede 100644
--- a/key/goKey.h
+++ b/key/goKey.h
@@ -1,5 +1,6 @@
 // Copyright 2016 The go-vgo Project Developers. 
 
+#include <stdlib.h>
 #include "../base/types.h"
 // #include "keycode.h"
 // #include "keypress.h"