diff --git a/stella/src/macosx/macOSXDisplay.h b/stella/src/macosx/macOSXDisplay.h
new file mode 100644
index 000000000..223d0d898
--- /dev/null
+++ b/stella/src/macosx/macOSXDisplay.h
@@ -0,0 +1,14 @@
+/* macOSXDisplay.h - Header for display size 
+   support functions for the
+   Macintosh OS X SDL port of Stella
+   Mark Grebe <atarimac@cox.net>
+   
+*/
+/* $Id: macOSXDisplay.h,v 1.1 2005-09-07 03:11:33 markgrebe Exp $ */
+
+
+extern "C" {
+uInt16 macOSXDisplayWidth(void);
+uInt16 macOSXDisplayHeight(void);
+}
+