@c -*-texinfo-*-
@c This is part of the GNU Emacs Lisp Reference Manual.
-@c Copyright (C) 1990, 1991, 1992, 1993, 1994, 1995, 1998, 1999, 2004
-@c Free Software Foundation, Inc.
+@c Copyright (C) 1990, 1991, 1992, 1993, 1994, 1995, 1998, 1999, 2002, 2003,
+@c 2004, 2005, 2006 Free Software Foundation, Inc.
@c See the file elisp.texi for copying conditions.
@setfilename ../info/windows
@node Windows, Frames, Buffers, Top
* Size of Window:: Accessing the size of a window.
* Resizing Windows:: Changing the size of a window.
* Coordinates and Windows:: Converting coordinates to windows.
+* Window Tree:: The layout and sizes of all windows in a frame.
* Window Configurations:: Saving and restoring the state of the screen.
* Window Hooks:: Hooks for scrolling, window size changes,
redisplay going past a certain point,
@end smallexample
Normally, Emacs indicates the border between two side-by-side windows
-with a scroll bar (@pxref{Window Frame Parameters,Scroll Bars}) or @samp{|}
+with a scroll bar (@pxref{Layout Parameters,Scroll Bars}) or @samp{|}
characters. The display table can specify alternative border
characters; see @ref{Display Tables}.
@end deffn
The following functions choose one of the windows on the screen,
offering various criteria for the choice.
-@defun get-lru-window &optional frame
+@defun get-lru-window &optional frame dedicated
This function returns the window least recently ``used'' (that is,
selected). If any full-width windows are present, it only considers
these. The selected window is always the most recently used window.
The selected window can be the least recently used window if it is the
only window. A newly created window becomes the least recently used
window until it is selected. A minibuffer window is never a
-candidate. Dedicated windows are never candidates, and if all
+candidate. Dedicated windows are never candidates unless the
+@var{dedicated} argument is non-@code{nil}, so if all
existing windows are dedicated, the value is @code{nil}.
The argument @var{frame} controls which windows are considered.
@end itemize
@end defun
-@defun get-largest-window &optional frame
+@defun get-largest-window &optional frame dedicated
This function returns the window with the largest area (height times
width). If there are no side-by-side windows, then this is the window
with the most lines. A minibuffer window is never a candidate.
-Dedicated windows are never candidates, and if all existing windows
+Dedicated windows are never candidates unless the
+@var{dedicated} argument is non-@code{nil}, so if all existing windows
are dedicated, the value is @code{nil}.
If there are two candidate windows of the same size, this function
widths of @var{window} remain unchanged. @xref{Fringes}.
@end defun
+@defvar buffer-display-count
+This buffer-local variable records the number of times a buffer is
+displayed in a window. It is incremented each time
+@code{set-window-buffer} is called for the buffer.
+@end defvar
+
@defun window-buffer &optional window
This function returns the buffer that @var{window} is displaying. If
@var{window} is omitted, this function returns the buffer for the
@defun set-window-point window position
This function positions point in @var{window} at position
@var{position} in @var{window}'s buffer. It returns @var{position}.
+
+If @var{window} is selected, and its buffer is current,
+this simply does @code{goto-char}.
@end defun
@node Window Start
@end defopt
@defopt scroll-preserve-screen-position
-If this option is non-@code{nil}, the scroll functions move point so
-that the vertical position of the cursor is unchanged, when that is
-possible.
+If this option is @code{t}, scrolling which would move the current
+point position out of the window chooses the new position of point
+so that the vertical position of the cursor is unchanged, if possible.
+
+If it is non-@code{nil} and not @code{t}, then the scrolling functions
+always preserve the vertical position of point, if possible.
@end defopt
@defopt next-screen-context-lines
bound for automatic scrolling, i.e. automatic scrolling will not
scroll a window to a column less than the specified one.
-@deffn Command scroll-left &optional count
+@deffn Command scroll-left &optional count set-minimum
This function scrolls the selected window @var{count} columns to the
left (or to the right if @var{count} is negative). The default
for @var{count} is the window width, minus 2.
-The return value is the total amount of leftward horizontal scrolling in
-effect after the change---just like the value returned by
-@code{window-hscroll} (below).
-@end deffn
-
-@deffn Command scroll-right &optional count
-This function scrolls the selected window @var{count} columns to the
-right (or to the left if @var{count} is negative). The default
-for @var{count} is the window width, minus 2.
-
The return value is the total amount of leftward horizontal scrolling in
effect after the change---just like the value returned by
@code{window-hscroll} (below).
Once you scroll a window as far right as it can go, back to its normal
position where the total leftward scrolling is zero, attempts to scroll
any farther right have no effect.
+
+If @var{set-minimum} is non-@code{nil}, the new scroll amount becomes
+the lower bound for automatic scrolling; that is, automatic scrolling
+will not scroll a window to a column less than the value returned by
+this function. Interactive calls pass non-@code{nil} for
+@var{set-minimum}.
+@end deffn
+
+@deffn Command scroll-right &optional count set-minimum
+This function scrolls the selected window @var{count} columns to the
+right (or to the left if @var{count} is negative). The default
+for @var{count} is the window width, minus 2. Aside from the direction
+of scrolling, this works just like @code{scroll-left}.
@end deffn
@defun window-hscroll &optional window
window size. Emacs does not permit overlapping windows or gaps between
windows, so resizing one window affects other windows.
-@deffn Command enlarge-window size &optional horizontal preserve-before
+@deffn Command enlarge-window size &optional horizontal
This function makes the selected window @var{size} lines taller,
stealing lines from neighboring windows. It takes the lines from one
window at a time until that window is used up, then takes from another.
size of a fixed-size window, @code{enlarge-window} gets an error
instead.
-If @var{preserve-before} is non-@code{nil}, this function does not
-change the size of the siblings above or to the left of the selected
-window. Only the size of the siblings below or to the right of the
-selected window are changed.
-
If @var{size} is negative, this function shrinks the window by
@minus{}@var{size} lines or columns. If that makes the window smaller
than the minimum size (@code{window-min-height} and
@end example
@end deffn
-@deffn Command shrink-window size &optional horizontal preserve-before
+@deffn Command shrink-window size &optional horizontal
This function is like @code{enlarge-window} but negates the argument
@var{size}, making the selected window smaller by giving lines (or
columns) to the other windows. If the window shrinks below
@end example
@end deffn
+@defun adjust-window-trailing-edge window delta horizontal
+This function makes the selected window @var{delta} lines taller or
+@var{delta} columns wider, by moving the bottom or right edge. This
+function does not delete other windows; if it cannot make the
+requested size adjustment, it signals an error. On success, this
+function returns @code{nil}.
+@end defun
+
@defun fit-window-to-buffer &optional window max-height min-height
This function makes @var{window} the right height to display its
contents exactly. If @var{window} is omitted or @code{nil}, it uses
argument because it always uses the frame that @var{window} is on.
@end defun
+@node Window Tree
+@section The Window Tree
+@cindex window tree
+
+ A @dfn{window tree} specifies the layout, size, and relationship
+between all windows in one frame.
+
+@defun window-tree &optional frame
+This function returns the window tree for frame @var{frame}.
+If @var{frame} is omitted, the selected frame is used.
+
+The return value is a list of the form @code{(@var{root} @var{mini})},
+where @var{root} represents the window tree of the frame's
+root window, and @var{mini} is the frame's minibuffer window.
+
+If the root window is not split, @var{root} is the root window itself.
+Otherwise, @var{root} is a list @code{(@var{dir} @var{edges} @var{w1}
+@var{w2} ...)} where @var{dir} is @code{nil} for a horizontal split,
+and @code{t} for a vertical split, @var{edges} gives the combined size and
+position of the subwindows in the split, and the rest of the elements
+are the subwindows in the split. Each of the subwindows may again be
+a window or a list representing a window split, and so on. The
+@var{edges} element is a list @code{(@var{left}@var{ top}@var{ right}@var{ bottom})}
+similar to the value returned by @code{window-edges}.
+@end defun
+
@node Window Configurations
@section Window Configurations
@cindex window configurations