diff --git a/input.c b/input.c
index 49f153d2..d356f721 100644
--- a/input.c
+++ b/input.c
@@ -1,4 +1,4 @@
-/* $Id: input.c,v 1.102 2009-11-08 23:02:56 tcunha Exp $ */
+/* $Id: input.c,v 1.103 2009-11-28 14:59:26 tcunha Exp $ */
 
 /*
  * Copyright (c) 2007 Nicholas Marriott <nicm@users.sourceforge.net>
@@ -266,6 +266,7 @@ input_parse(struct window_pane *wp)
 
 	ictx->wp = wp;
 
+	/* If there is a mode set, don't want to update the screen. */
 	if (wp->mode == NULL)
 		screen_write_start(&ictx->ctx, wp, &wp->base);
 	else
diff --git a/tty.c b/tty.c
index 1fb4a140..2a1d4b1f 100644
--- a/tty.c
+++ b/tty.c
@@ -1,4 +1,4 @@
-/* $Id: tty.c,v 1.178 2009-11-28 14:56:11 tcunha Exp $ */
+/* $Id: tty.c,v 1.179 2009-11-28 14:59:26 tcunha Exp $ */
 
 /*
  * Copyright (c) 2007 Nicholas Marriott <nicm@users.sourceforge.net>
@@ -534,6 +534,7 @@ tty_write(void (*cmdfn)(
 	struct client		*c;
 	u_int		 	 i;
 
+	/* wp can be NULL if updating the screen but not the terminal. */
 	if (wp == NULL)
 		return;