diff --git a/cpdfcommandrun.ml b/cpdfcommandrun.ml
index 501370b..63b157e 100644
--- a/cpdfcommandrun.ml
+++ b/cpdfcommandrun.ml
@@ -1 +1,4 @@
-let _ = Cpdfcommand.go ()
+let _ =
+  match Filename.basename Sys.argv.(0) with
+    "cpdf.top" -> ()
+  | _ -> Cpdfcommand.go ()