diff --git a/Modules/main.c b/Modules/main.c
index e123976..0d17c34 100644
--- a/Modules/main.c
+++ b/Modules/main.c
@@ -219,7 +219,8 @@
 }
 
 
-/* Return the program name -- some code out there needs this. */
+/* Return the program name -- some code out there needs this
+   (currently _tkinter.c and importdl.c). */
 
 char *
 getprogramname()