diff --git a/lib/cdio.c b/lib/cdio.c
index d138b797..b648839d 100644
--- a/lib/cdio.c
+++ b/lib/cdio.c
@@ -1,5 +1,5 @@
 /*
-    $Id: cdio.c,v 1.5 2003/04/02 14:54:52 rocky Exp $
+    $Id: cdio.c,v 1.6 2003/04/04 00:41:10 rocky Exp $
 
     Copyright (C) 2003 Rocky Bernstein <rocky@panix.com>
     Copyright (C) 2001 Herbert Valerio Riedel <hvr@gnu.org>
@@ -28,7 +28,7 @@
 #include "logging.h"
 #include "cdio_private.h"
 
-static const char _rcsid[] = "$Id: cdio.c,v 1.5 2003/04/02 14:54:52 rocky Exp $";
+static const char _rcsid[] = "$Id: cdio.c,v 1.6 2003/04/04 00:41:10 rocky Exp $";
 
 
 const char *track_format2str[5] = 
@@ -151,6 +151,8 @@ cdio_get_arg (const CdIo *obj, const char key[])
 
 /*!
   Return a string containing the default CD device if none is specified.
+
+  NULL is returned if we couldn't get a default device.
  */
 char *
 cdio_get_default_device (const CdIo *obj)
diff --git a/lib/cdio.h b/lib/cdio.h
index c951c6ad..f577d37e 100644
--- a/lib/cdio.h
+++ b/lib/cdio.h
@@ -1,5 +1,5 @@
 /*
-    $Id: cdio.h,v 1.5 2003/04/03 12:16:27 rocky Exp $
+    $Id: cdio.h,v 1.6 2003/04/04 00:41:10 rocky Exp $
 
     Copyright (C) 2001 Herbert Valerio Riedel <hvr@gnu.org>
     Copyright (C) 2003 Rocky Bernstein <rocky@panix.com>
@@ -107,6 +107,8 @@ extern "C" {
 
   /*!
     Return a string containing the default CD device if none is specified.
+
+    NULL is returned if we couldn't get a default device.
   */
   char * cdio_get_default_device (const CdIo *obj);