diff --git a/uLispZero.ino b/ulisp-zero.ino
similarity index 99%
rename from uLispZero.ino
rename to ulisp-zero.ino
index 1809d71..768ced9 100644
--- a/uLispZero.ino
+++ b/ulisp-zero.ino
@@ -88,6 +88,8 @@ volatile char Escape = 0;
 
 // Forward references
 object *tee;
+void error (PGM_P string);
+void pfstring (PGM_P s);
 
 // Set up workspace