@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 Free Software Foundation, Inc.
+@c 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009 Free Software Foundation, Inc.
@c See the file elisp.texi for copying conditions.
@setfilename ../../info/windows
@node Windows, Frames, Buffers, Top
@deffn Command split-window &optional window size horizontal
This function splits a new window out of @var{window}'s screen area. It
-returns the new window. @var{window} defaults to the selected window.
-When you split the selected window, it remains selected.
+returns the new window. The default for @var{window} is the selected
+window. When you split the selected window, it remains selected.
If @var{horizontal} is non-@code{nil}, then @var{window} splits into two
side by side windows. The original window keeps the leftmost @var{size}
@deffn Command delete-window &optional window
This function removes @var{window} from display and returns @code{nil}.
-@var{window} defaults to the selected window. An error is signaled if
-@var{window} is the only window on its frame.
+The default for @var{window} is the selected window. An error is
+signaled if @var{window} is the only window on its frame.
@end deffn
@deffn Command delete-other-windows &optional window
This function makes @var{window} the only window on its frame, by
-deleting the other windows in that frame. @var{window} defaults to the
-selected window. The return value is @code{nil}.
+deleting the other windows in that frame. The default for @var{window}
+is the selected window. The return value is @code{nil}.
@end deffn
@deffn Command delete-windows-on &optional buffer-or-name frame
This function deletes all windows showing @var{buffer-or-name}. If
-there are no windows showing @var{buffer-or-name}, it does nothing.
-@var{buffer-or-name} may be a buffer or the name of an existing buffer
-and defaults to the current buffer.
+there are no windows showing @var{buffer-or-name}, it does nothing. The
+optional argument @var{buffer-or-name} may be a buffer or the name of an
+existing buffer and defaults to the current buffer.
@code{delete-windows-on} operates frame by frame. If a frame has
several windows showing different buffers, then those showing
(@pxref{Dedicated Windows}), and there are other frames left, that
window's frame is deleted.
-The argument @var{frame} specifies which frames to operate on. This
-function does not use it in quite the same way as the other functions
-which scan all windows; specifically, the values @code{t} and @code{nil}
-have the opposite of their meanings in other functions. Here are the
-full details:
+The optional argument @var{frame} specifies which frames to operate on.
+This function does not use it in quite the same way as the other
+functions which scan all windows; specifically, the values @code{t} and
+@code{nil} have the opposite of their meanings in other functions. Here
+are the full details:
@itemize @bullet
@item
only window. A newly created window becomes the least recently used
window until it is selected. A minibuffer window is never a candidate.
A dedicated window (@pxref{Dedicated Windows}) is never a candidate
-unless the @var{dedicated} argument is non-@code{nil}, so if all
-existing windows are dedicated, the function returns @code{nil}.
+unless the optional argument @var{dedicated} is non-@code{nil}.
-The argument @var{frame} specifies which windows are considered.
+The optional argument @var{frame} specifies which windows are
+considered.
@itemize @bullet
@item
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. A
dedicated window (@pxref{Dedicated Windows}) is never a candidate unless
-the @var{dedicated} argument is non-@code{nil}, so if all existing
-windows are dedicated, the function returns @code{nil}.
+the optional argument @var{dedicated} is non-@code{nil}.
If there are two candidate windows of the same size, this function
prefers the one that comes first in the cyclic ordering of windows,
starting from the selected window (@pxref{Cyclic Window Ordering}).
-The argument @var{frame} specifies which set of windows to consider, see
-@code{get-lru-window} above.
+The optional argument @var{frame} specifies which set of windows to
+consider, see @code{get-lru-window} above.
@end defun
@cindex window that satisfies a predicate
@cindex minibuffer window, and @code{next-window}
This function returns the window following @var{window} in the cyclic
ordering of windows. This is the window @kbd{C-x o} selects if typed
-when @var{window} is selected. @var{window} defaults to the selected
-window.
+when @var{window} is selected. The default for @var{window} is the
+selected window.
-The value of the argument @var{minibuf} specifies whether the minibuffer
-is included in the window order. Normally, when @var{minibuf} is
-@code{nil}, the minibuffer is included only if it is currently
-``active''; this matches the behavior of @kbd{C-x o}. (The minibuffer
-window is active while the minibuffer is in use; see @ref{Minibuffers}.)
+The value of the optional argument @var{minibuf} specifies whether the
+minibuffer is included in the window order. Normally, when
+@var{minibuf} is @code{nil}, the minibuffer is included only if it is
+currently ``active''; this matches the behavior of @kbd{C-x o}. (The
+minibuffer window is active while the minibuffer is in use; see
+@ref{Minibuffers}.)
If @var{minibuf} is @code{t}, the cyclic ordering includes the
minibuffer window even if it is not active. If @var{minibuf} is neither
@code{t} nor @code{nil}, the minibuffer window is not included even if
it is active.
-The argument @var{all-frames} specifies which frames to consider. Here
-are the possible values and their meanings:
+The optional argument @var{all-frames} specifies which frames to
+consider. Here are the possible values and their meanings:
@table @asis
@item @code{nil}
the selected window. In an interactive call, @var{count} is the numeric
prefix argument.
-The argument @var{all-frames} has the same meaning as in
+The optional argument @var{all-frames} has the same meaning as in
@code{next-window}, but the @var{minibuf} argument of @code{next-window}
is always effectively @code{nil}. This function returns @code{nil}.
@end deffn
@defun window-list &optional frame minibuf window
This function returns a list of all windows on @var{frame}, starting
-with @var{window}. @var{frame} defaults to the selected frame;
-@var{window} defaults to the selected window.
+with @var{window}. The default for @var{frame} is the selected frame;
+the default for @var{window} is the selected window.
The value of @var{minibuf} specifies if the minibuffer window shall be
included in the result list. If @var{minibuf} is @code{t}, the result
@defun set-window-buffer window buffer-or-name &optional keep-margins
This function makes @var{window} display @var{buffer-or-name} as its
-contents. It returns @code{nil}. @var{buffer-or-name} must be a
-buffer, or the name of an existing buffer. This is the fundamental
-primitive for changing which buffer is displayed in a window, and all
-ways of doing that call this function.
+contents. It returns @code{nil}. The default for @var{window} is the
+selected window. The argument @var{buffer-or-name} must specify a
+buffer or the name of an existing buffer.
+
+@code{set-window-buffer} is the fundamental primitive for changing which
+buffer is displayed in a window, and all ways of doing that call this
+function.
@example
@group
However, if @var{keep-margins} is non-@code{nil}, display margins and
fringe widths of @var{window} remain unchanged. @xref{Fringes}.
-This function signals an error when @var{window} is @dfn{strongly}
-dedicated to its buffer (@pxref{Dedicated Windows}) and does not already
-display @var{buffer-or-name}.
+@code{set-window-buffer} signals an error when @var{window} is
+@dfn{strongly} dedicated to its buffer (@pxref{Dedicated Windows}) and
+does not already display @var{buffer-or-name}.
-This function runs @code{window-scroll-functions} before running
-@code{window-configuration-change-hook}.
+Note that this function runs @code{window-scroll-functions} before
+running @code{window-configuration-change-hook}.
@end defun
@defvar buffer-display-count
@end defvar
@defun window-buffer &optional window
-This function returns the buffer that @var{window} is displaying.
-@var{window} defaults to the selected window.
+This function returns the buffer that @var{window} is displaying. The
+default for @var{window} is the selected window.
@example
@group
cyclic ordering of windows, starting from the selected window.
@xref{Cyclic Window Ordering}.
-@var{BUFFER-OR-NAME} may be a buffer or a buffer name and defaults to
-the current buffer. The argument @var{all-frames} specifies which
-windows to consider:
+The argument @var{BUFFER-OR-NAME} may be a buffer or a buffer name and
+defaults to the current buffer. The optional argument @var{all-frames}
+specifies which windows to consider:
@itemize @bullet
@item
@defun get-buffer-window-list &optional buffer-or-name minibuf all-frames
This function returns a list of all windows currently displaying
-@var{buffer-or-name}. @var{buffer-or-name} may be a buffer or the name
-of an existing buffer and defaults to the current buffer.
+@var{buffer-or-name}. The argument @var{buffer-or-name} may be a buffer
+or the name of an existing buffer and defaults to the current buffer.
The two remaining arguments work like the same-named arguments of
@code{next-window}; they are @emph{not} like the optional arguments of
displays the buffer in the selected window. This means that a human can
see the buffer and subsequent keyboard commands will apply to it.
Contrast this with @code{set-buffer}, which makes @var{buffer-or-name}
-the current buffer but does not display it in the selected window,
+the current buffer but does not display it in the selected window;
see @ref{Current Buffer}.
If @var{buffer-or-name} is @code{nil}, @code{switch-to-buffer} chooses a
for the described features.
@deffn Command switch-to-buffer-other-window buffer-or-name &optional norecord
-This function makes @var{buffer-or-name} the current buffer, displays it
-in a window not currently selected, and selects that window. The
-handling of the buffer is the same as in @code{switch-to-buffer}.
+This function makes the buffer specified by @var{buffer-or-name} current
+and displays it in a window not currently selected. It then selects
+that window. The handling of the buffer is the same as in
+@code{switch-to-buffer}.
The currently selected window is absolutely never used to do the job.
If it is the only window, then it is split to make a distinct window for
don't care which other buffer is used; you just want to make sure that
@var{buffer-or-name} is no longer displayed.
-@var{buffer-or-name} may be a buffer or the name of an existing buffer
-and defaults to the current buffer.
+The argument @var{buffer-or-name} may be a buffer or the name of an
+existing buffer and defaults to the current buffer.
If a window displaying @var{buffer-or-name} is dedicated
(@pxref{Dedicated Windows}), and is not the only window on its frame,
This command makes @var{buffer-or-name} appear in some window, but it
does not select that window and does not make the buffer specified by
@var{buffer-or-name} current. The identity of the selected window is
-unaltered by this function. @var{buffer-or-name} must be a buffer, or
-the name of an existing buffer.
+unaltered by this function. The argument @var{buffer-or-name} must be a
+buffer or the name of an existing buffer.
@var{not-this-window} non-@code{nil} means to display the specified
buffer in a window other than the selected one, even if it is already
@code{display-buffer} returns the window chosen to display
@var{buffer-or-name}.
-If the argument @var{frame} is non-@code{nil}, it specifies which frames
-to check when deciding whether the buffer is already displayed. If the
-buffer is already displayed in some window on one of these frames,
-@code{display-buffer} simply returns that window. Here are the possible
-values of @var{frame}:
+If the optional argument @var{frame} is non-@code{nil}, it specifies
+which frames to check when deciding whether the buffer is already
+displayed. If the buffer is already displayed in some window on one of
+these frames, @code{display-buffer} simply returns that window. Here
+are the possible values of @var{frame}:
@itemize @bullet
@item
@defopt pop-up-windows
This variable specifies whether @code{display-buffer} is allowed to
split (@pxref{Splitting Windows}) an existing window . If it is
-non-@code{nil}, @code{display-buffer} tries to the split the largest or
-least recently used window on the selected frame. (If the selected
-frame is a minibuffer-only frame, it tries to split a window on another
-frame instead.) If @code{pop-up-windows} is nil or the variable
-@code{pop-up-frames} (see below) is non-@code{nil},
+non-@code{nil}, @code{display-buffer} tries to the split the largest
+or least recently used window on the selected frame. (If the selected
+frame is a minibuffer-only frame, it tries to split a window on
+another frame instead.) If @code{pop-up-windows} is @code{nil} or the
+variable @code{pop-up-frames} (see below) is non-@code{nil},
@code{display-buffer} does not split any window.
@end defopt
@end defopt
@defopt pop-up-frame-alist
-This variable holds an alist specifying frame parameters used when
-@code{display-buffer} makes a new frame. @xref{Frame Parameters}, for
-more information about frame parameters.
+This variable holds an alist specifying frame parameters used by the
+default value of @code{pop-up-frame-function} for making new frames.
+@xref{Frame Parameters}, for more information about frame parameters.
@end defopt
@defopt special-display-buffer-names
buffer and @code{nil} otherwise. More precisely, the return value is
the value assigned by the last call of @code{set-window-dedicated-p} for
@var{window} or @code{nil} if that function was never called with
-@var{window} as its argument. @var{window} defaults to the selected
-window.
+@var{window} as its argument. The default for @var{window} is the
+selected window.
@end defun
@defun set-window-dedicated-p window flag
@end itemize
@cindex cursor
-As far as the user is concerned, point is where the cursor is, and
+ As far as the user is concerned, point is where the cursor is, and
when the user switches to another buffer, the cursor jumps to the
position of point in that buffer.
@defun window-point &optional window
This function returns the current position of point in @var{window}.
For a nonselected window, this is the value point would have (in that
-window's buffer) if that window were selected. @var{window} defaults to
-the selected window.
+window's buffer) if that window were selected. The default for
+@var{window} is the selected window.
When @var{window} is the selected window and its buffer is also the
current buffer, the value returned is the same as point in that buffer.
@cindex window end position
@defun window-end &optional window update
This function returns the position where display of its buffer ends in
-@var{window}. @var{window} defaults to the selected window.
+@var{window}. The default for @var{window} is the selected window.
Simply changing the buffer text or moving point does not update the
value that @code{window-end} returns. The value is updated only when
@end defun
@defun window-line-height &optional line window
-This function returns information about text line @var{line} in @var{window}.
-If @var{line} is one of @code{header-line} or @code{mode-line},
-@code{window-line-height} returns information about the corresponding
-line of the window. Otherwise, @var{line} is a text line number
-starting from 0. A negative number counts from the end of the window.
-The argument @var{line} defaults to the current line in @var{window};
-@var{window}, to the selected window.
+This function returns the height of text line @var{line} in
+@var{window}. If @var{line} is one of @code{header-line} or
+@code{mode-line}, @code{window-line-height} returns information about
+the corresponding line of the window. Otherwise, @var{line} is a text
+line number starting from 0. A negative number counts from the end of
+the window. The default for @var{line} is the current line in
+@var{window}; the default for @var{window} is the selected window.
If the display is not up to date, @code{window-line-height} returns
@code{nil}. In that case, @code{pos-visible-in-window-p} may be used
@cindex vertical fractional scrolling
@cindex vertical scroll position
-@dfn{Vertical fractional scrolling} means shifting text in a window up
-or down by a specified multiple or fraction of a line. Each window has
-a @dfn{vertical scroll position}, which is a number, never less than
+ @dfn{Vertical fractional scrolling} means shifting text in a window
+up or down by a specified multiple or fraction of a line. Each window
+has a @dfn{vertical scroll position}, which is a number, never less than
zero. It specifies how far to raise the contents of the window.
Raising the window contents generally makes all or part of some lines
disappear off the top, and all or part of some other lines appear at the
bottom. The usual value is zero.
-The vertical scroll position is measured in units of the normal line
+ The vertical scroll position is measured in units of the normal line
height, which is the height of the default font. Thus, if the value is
.5, that means the window contents are scrolled up half the normal line
height. If it is 3.3, that means the window contents are scrolled up
somewhat over three times the normal line height.
-What fraction of a line the vertical scrolling covers, or how many
+ What fraction of a line the vertical scrolling covers, or how many
lines, depends on what the lines contain. A value of .5 could scroll a
line whose height is very short off the screen, while a value of 3.3
could scroll just part of the way through a tall line or an image.
@defun window-vscroll &optional window pixels-p
This function returns the current vertical scroll position of
-@var{window}. @var{window} defaults to the selected window. If
-@var{pixels-p} is non-@code{nil}, the return value is measured in
+@var{window}. The default for @var{window} is the selected window.
+If @var{pixels-p} is non-@code{nil}, the return value is measured in
pixels, rather than in units of the normal line height.
@example
@defun window-hscroll &optional window
This function returns the total leftward horizontal scrolling of
@var{window}---the number of columns by which the text in @var{window}
-is scrolled left past the left margin. @var{window} defaults to the
-selected window.
+is scrolled left past the left margin. The default for
+@var{window} is the selected window.
The return value is never negative. It is zero when no horizontal
scrolling has been done in @var{window} (which is usually the case).
@end example
@end defun
-Here is how you can determine whether a given position @var{position} is
-off the screen due to horizontal scrolling:
+ Here is how you can determine whether a given position @var{position}
+is off the screen due to horizontal scrolling:
@example
@group
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. @var{window} defaults to
-the selected window.
+value of @code{frame-height} on that frame. The default for
+@var{window} is the selected window.
@example
@group
@end defun
@defun window-width &optional window
-This function returns the number of columns in @var{window}.
-@var{window} defaults to the selected window.
+This function returns the number of columns in @var{window}. The
+default for @var{window} is the selected window.
The return value does not include the window's scroll bar or the column
of @samp{|} characters that separates side-by-side windows. Moreover,
@defun window-full-width-p &optional window
This function returns non-@code{nil} if @var{window} is as wide as the
-frame that contains it; otherwise @code{nil}. @var{window} defaults to
-the selected window.
+frame that contains it; otherwise @code{nil}. The default for
+@var{window} is the selected window.
@end defun
@defun window-edges &optional window
This function returns a list of the edge coordinates of @var{window}.
-@var{window} defaults to the selected window.
+The default for @var{window} is the selected window.
The order of the list is @code{(@var{left} @var{top} @var{right}
@var{bottom})}, all elements relative to 0, 0 at the top left corner of
@cindex changing window size
@cindex window size, changing
-The window size functions fall into two classes: high-level commands
+ The window size functions fall into two classes: high-level commands
that change the size of windows and low-level functions that access
window size. Emacs does not permit overlapping windows or gaps between
windows, so resizing a window always affects at least one other window.
@defun fit-window-to-buffer &optional window max-height min-height
This function makes @var{window} the right height to display its
-contents exactly. @var{window} defaults to the selected window.
-
-The argument @var{max-height} specifies the maximum height the window
-is allowed to be; @code{nil} means use the frame height. The argument
-@var{min-height} specifies the minimum height for the window;
-@code{nil} means use @code{window-min-height}. All these height
-values include the mode line and/or header line.
+contents exactly. The default for @var{window} is the selected window.
+
+The optional argument @var{max-height} specifies the maximum height the
+window is allowed to be; @code{nil} means use the maximum permissible
+height of a window on @var{window}'s frame. The optional argument
+@var{min-height} specifies the minimum height for the window; @code{nil}
+means use @code{window-min-height}. All these height values include the
+mode line and/or header line.
+
+This function can delete windows when their height shrinks below
+@var{min-height}. It returns non-@code{nil} if it orderly resized
+@var{window}, and @code{nil} otherwise.
@end defun
@deffn Command shrink-window-if-larger-than-buffer &optional window
This command shrinks @var{window} vertically to be as small as possible
while still showing the full contents of its buffer---but not less than
-@code{window-min-height} lines. @var{window} defaults to the selected
-window.
+@code{window-min-height} lines. The default for @var{window} is
+the selected window.
However, this command does nothing if the window is already too small to
display the whole text of the buffer, or if part of the contents are
@code{window-min-height} automatically deletes it, and no window may be
created shorter than this. The value is measured in line units. When
the window wants a mode line and/or a header line, they are counted as
-one line each. The default value of this variable is @code{4}. A value
-less than @code{1} is ignored.
+one line each. The default value is @code{4}. A value less than
+@code{1} is ignored.
@end defopt
@defopt window-min-width
@defun current-window-configuration &optional frame
This function returns a new object representing @var{frame}'s current
-window configuration. @var{frame} defaults to the selected frame.
+window configuration. The default for @var{frame} is the selected
+frame.
@end defun
@defun set-window-configuration configuration
additional information with windows.
@defun window-parameter window parameter
-This function returns @var{window}'s value for @var{parameter}.
-@var{window} defaults to the selected window. If @var{window} has no
-setting for @var{parameter}, this function returns @code{nil}.
+This function returns @var{window}'s value for @var{parameter}. The
+default for @var{window} is the selected window. If @var{window}
+has no setting for @var{parameter}, this function returns @code{nil}.
@end defun
@defun window-parameters &optional window
This function returns all parameters of @var{window} and their values.
-@var{window} defaults to the selected window. The return value is an
-association list of elements of the form @code{(@var{parameter}
+The default for @var{window} is the selected window. The return value
+is an association list of elements of the form @code{(@var{parameter}
. @var{value})}.
@end defun
@defun set-window-parameter window parameter value
This function sets @var{window}'s value of @var{parameter} to
-@var{value} and returns @var{value}. @var{window} defaults to the
-selected window.
+@var{value} and returns @var{value}. The default for @var{window}
+is the selected window.
@end defun
Currently, window parameters are not saved in window configurations and
Windows}) is what you need here.
@end defvar
-@defvar redisplay-end-trigger-functions
-This abnormal hook is run whenever redisplay in a window uses text that
-extends past a specified end trigger position. You set the end trigger
-position with @code{set-window-redisplay-end-trigger}. The functions
-are called with two arguments: the window, and the end trigger position.
-Storing @code{nil} for the end trigger position turns off the feature,
-and the trigger value is automatically reset to @code{nil} just after
-the hook is run.
-@end defvar
-
-@defun set-window-redisplay-end-trigger window position
-This function sets @var{window}'s end trigger position at
-@var{position}.
-@end defun
-
-@defun window-redisplay-end-trigger &optional window
-This function returns @var{window}'s current end trigger position.
-If @var{window} is @code{nil} or omitted, it uses the selected window.
-@end defun
-
@defvar window-configuration-change-hook
A normal hook that is run every time you change the window configuration
of an existing frame. This includes splitting or deleting windows,
frame selected.
@end defvar
+ In addition, you can use @code{jit-lock-register} to register a Font
+Lock fontification function, which will be called whenever part of the
+buffer needs to be refontified (usually because it has been changed).
+@xref{Other Font Lock Variables}.
+
@ignore
arch-tag: 3f6c36e8-df49-4986-b757-417feed88be3
@end ignore