diff --git a/ZlibDbg/App/main.vp b/ZlibDbg/App/main.vp
index 2655ce6..375fb92 100644
--- a/ZlibDbg/App/main.vp
+++ b/ZlibDbg/App/main.vp
@@ -5,6 +5,7 @@ import zlib.zinflate as zinflate
 import zlib.zdef as zdef
 import string
 import stdlib
+import stdio
 import testcheck
 import t, c