(Size and Position): Explain meaning of frame pixel width and height.

lispref/ChangeLog

@@ -2,6 +2,7 @@
 
 	* frames.texi (Size Parameters): Fix typo.
 	(Basic Parameters): For `title', refer to title bar.
+	(Size and Position): Explain meaning of frame pixel width and height.
 
 2007-12-23  Richard Stallman  <rms@gnu.org>
 

lispref/frames.texi

@@ -800,8 +800,14 @@ of the frame is normally the same as the size of the terminal screen.
 
 @defun frame-pixel-height &optional frame
 @defunx frame-pixel-width &optional frame
-These functions return the height and width of @var{frame}, measured in
-pixels.  If you don't supply @var{frame}, they use the selected frame.
+These functions return the height and width of the main display area
+of @var{frame}, measured in pixels.  If you don't supply @var{frame},
+they use the selected frame.
+
+These values include the internal borders, and windows' scroll bars
+and fringes (which belong to individual windows, not to the frame
+itself), but do not include menu bars or tool bars (except when using
+X without an X toolkit).
 @end defun
 
 @defun frame-char-height &optional frame