@c -*-texinfo-*-
@c This is part of the GNU Emacs Lisp Reference Manual.
@c Copyright (C) 1990, 1991, 1992, 1993, 1994, 1995, 1998, 1999, 2001,
-@c 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009 Free Software Foundation, Inc.
+@c 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009
+@c Free Software Foundation, Inc.
@c See the file elisp.texi for copying conditions.
@setfilename ../../info/windows
@node Windows, Frames, Buffers, Top
The following three functions return size information about a window:
@defun window-height &optional window
-This function returns the number of lines in @var{window}, including its
-mode line and header line, if any. If @var{window} fills its entire
-frame except for the echo area, this is typically one less than the
-value of @code{frame-height} on that frame. The default for
-@var{window} is the selected window.
+This function returns the number of lines in @var{window} (by default
+the selected window), including any mode line and header line.
+The result is almost always less than the value of @code{frame-height}
+for the associated frame, because the latter also includes any echo
+area. Depending on the toolkit in use, the frame height can also
+include the menu bar and tool bar (@pxref{Size and Position}).
+Therefore in general it is not straightforward to compare window and
+frame heights (see @code{window-full-height-p} below).
@example
@group
mode line (if any) or the header line (if any).
@end defun
+@defun window-full-height-p &optional window
+This function returns non-@code{nil} if @var{window} is as tall as the
+frame that contains it. The default for @var{window} is the selected
+window.
+@end defun
+
@defun window-width &optional window
This function returns the number of columns in @var{window}. The
default for @var{window} is the selected window.