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660 lines
28 KiB
Plaintext
@c This is part of the Emacs manual.
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@c Copyright (C) 1985, 1986, 1987, 1993, 1994, 1995, 1997, 2000, 2001,
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@c 2002, 2003, 2004, 2005, 2006 Free Software Foundation, Inc.
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@c See file emacs.texi for copying conditions.
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@node Buffers, Windows, Files, Top
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@chapter Using Multiple Buffers
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@cindex buffers
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The text you are editing in Emacs resides in an object called a
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@dfn{buffer}. Each time you visit a file, a buffer is created to hold the
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file's text. Each time you invoke Dired, a buffer is created to hold the
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directory listing. If you send a message with @kbd{C-x m}, a buffer named
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@samp{*mail*} is used to hold the text of the message. When you ask for a
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command's documentation, that appears in a buffer called @samp{*Help*}.
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@cindex selected buffer
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@cindex current buffer
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At any time, one and only one buffer is @dfn{current}. It is also
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called the @dfn{selected buffer}. Often we say that a command operates on
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``the buffer'' as if there were only one; but really this means that the
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command operates on the current buffer (most commands do).
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When Emacs has multiple windows, each window has its own chosen
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buffer and displays it; at any time, only one of the windows is
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selected, and its chosen buffer is the current buffer. Each window's
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mode line normally displays the name of the window's chosen buffer
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(@pxref{Windows}).
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Each buffer has a name, which can be of any length, and you can select
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any buffer by giving its name. Most buffers are made by visiting files,
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and their names are derived from the files' names. But you can also create
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an empty buffer with any name you want. A newly started Emacs has a buffer
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named @samp{*scratch*} which can be used for evaluating Lisp expressions in
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Emacs. The distinction between upper and lower case matters in buffer
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names.
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Each buffer records individually what file it is visiting, whether it is
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modified, and what major mode and minor modes are in effect in it
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(@pxref{Major Modes}). Any Emacs variable can be made @dfn{local to} a
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particular buffer, meaning its value in that buffer can be different from
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the value in other buffers. @xref{Locals}.
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@cindex buffer size, maximum
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A buffer's size cannot be larger than some maximum, which is defined
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by the largest buffer position representable by the @dfn{Emacs integer}
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data type. This is because Emacs tracks buffer positions using that
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data type. For 32-bit machines, the largest buffer size is 256
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megabytes.
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@menu
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* Select Buffer:: Creating a new buffer or reselecting an old one.
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* List Buffers:: Getting a list of buffers that exist.
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* Misc Buffer:: Renaming; changing read-onlyness; copying text.
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* Kill Buffer:: Killing buffers you no longer need.
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* Several Buffers:: How to go through the list of all buffers
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and operate variously on several of them.
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* Indirect Buffers:: An indirect buffer shares the text of another buffer.
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* Buffer Convenience:: Convenience and customization features for
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buffer handling.
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@end menu
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@node Select Buffer
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@section Creating and Selecting Buffers
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@cindex change buffers
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@cindex switch buffers
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@table @kbd
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@item C-x b @var{buffer} @key{RET}
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Select or create a buffer named @var{buffer} (@code{switch-to-buffer}).
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@item C-x 4 b @var{buffer} @key{RET}
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Similar, but select @var{buffer} in another window
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(@code{switch-to-buffer-other-window}).
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@item C-x 5 b @var{buffer} @key{RET}
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Similar, but select @var{buffer} in a separate frame
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(@code{switch-to-buffer-other-frame}).
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@item C-x @key{LEFT}
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Select the previous buffer in the list of existing buffers.
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@item C-x @key{RIGHT}
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Select the next buffer in the list of existing buffers.
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@item C-u M-g M-g
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@itemx C-u M-g g
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Read a number @var{n} and move to line @var{n} in the most recently
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selected buffer other than the current buffer.
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@end table
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@kindex C-x b
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@findex switch-to-buffer
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To select the buffer named @var{bufname}, type @kbd{C-x b @var{bufname}
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@key{RET}}. This runs the command @code{switch-to-buffer} with argument
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@var{bufname}. You can use completion to enter the buffer
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name (@pxref{Completion}). An empty argument to @kbd{C-x b}
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specifies the buffer that was current most recently among those not
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now displayed in any window.
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@kindex C-x @key{LEFT}
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@kindex C-x @key{RIGHT}
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@findex next-buffer
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@findex previous-buffer
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For conveniently switching between a few buffers, use the commands
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@kbd{C-x @key{LEFT}} and @kbd{C-x @key{RIGHT}}. @kbd{C-x @key{RIGHT}}
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(@code{previous-buffer}) selects the previous buffer (following the order
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of most recent selection in the current frame), while @kbd{C-x @key{LEFT}}
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(@code{next-buffer}) moves through buffers in the reverse direction.
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@kindex C-x 4 b
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@findex switch-to-buffer-other-window
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@vindex even-window-heights
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To select a buffer in a window other than the current one, type
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@kbd{C-x 4 b @var{bufname} @key{RET}}. This runs the command
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@code{switch-to-buffer-other-window} which displays the buffer
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@var{bufname} in another window. By default, if displaying the buffer
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causes two vertically adjacent windows to be displayed, the heights of
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those windows are evened out; to countermand that and preserve the
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window configuration, set the variable @code{even-window-heights} to
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@code{nil}.
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@kindex C-x 5 b
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@findex switch-to-buffer-other-frame
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Similarly, @kbd{C-x 5 b @var{buffer} @key{RET}} runs the command
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@code{switch-to-buffer-other-frame} which selects a buffer in another
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frame.
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@vindex display-buffer-reuse-frames
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You can control how certain buffers are handled by these commands by
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customizing the variables @code{special-display-buffer-names},
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@code{special-display-regexps}, @code{same-window-buffer-names}, and
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@code{same-window-regexps}. See @ref{Force Same Window}, and
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@ref{Special Buffer Frames}, for more about these variables. In
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addition, if the value of @code{display-buffer-reuse-frames} is
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non-@code{nil}, and the buffer you want to switch to is already
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displayed in some frame, Emacs will just raise that frame.
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Most buffers are created by visiting files, or by Emacs commands that
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want to display some text, but you can also create a buffer explicitly
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by typing @kbd{C-x b @var{bufname} @key{RET}}. This makes a new, empty
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buffer that is not visiting any file, and selects it for editing. Such
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buffers are used for making notes to yourself. If you try to save one,
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you are asked for the file name to use. The new buffer's major mode is
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determined by the value of @code{default-major-mode} (@pxref{Major
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Modes}).
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Note that @kbd{C-x C-f}, and any other command for visiting a file,
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can also be used to switch to an existing file-visiting buffer.
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@xref{Visiting}.
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@kbd{C-u M-g M-g}, that is @code{goto-line} with a prefix argument
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of just @kbd{C-u}, reads a number @var{n} using the minibuffer,
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selects the most recently selected buffer other than the current
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buffer in another window, and then moves point to the beginning of
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line number @var{n} in that buffer. This is mainly useful in a buffer
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that refers to line numbers in another buffer: if point is on or just
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after a number, @code{goto-line} uses that number as the default for
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@var{n}. Note that prefix arguments other than just @kbd{C-u} behave
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differently. @kbd{C-u 4 M-g M-g} goes to line 4 in the @emph{current}
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buffer, without reading a number from the minibuffer. (Remember that
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@kbd{M-g M-g} without prefix argument reads a number @var{n} and then
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moves to line number @var{n} in the current buffer.)
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Emacs uses buffer names that start with a space for internal purposes.
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It treats these buffers specially in minor ways---for example, by
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default they do not record undo information. It is best to avoid using
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such buffer names yourself.
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@node List Buffers
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@section Listing Existing Buffers
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@table @kbd
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@item C-x C-b
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List the existing buffers (@code{list-buffers}).
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@end table
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@cindex listing current buffers
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@kindex C-x C-b
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@findex list-buffers
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To display a list of existing buffers, type @kbd{C-x C-b}. Each
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line in the list shows one buffer's name, major mode and visited file.
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The buffers are listed in the order that they were current; the
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buffers that were current most recently come first.
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@samp{*} in the first field of a line indicates the buffer is
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``modified.'' If several buffers are modified, it may be time to save
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some with @kbd{C-x s} (@pxref{Save Commands}). @samp{%} indicates a
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read-only buffer. @samp{.} marks the current buffer. Here is an
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example of a buffer list:@refill
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@smallexample
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CRM Buffer Size Mode File
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. * .emacs 3294 Emacs-Lisp ~/.emacs
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% *Help* 101 Help
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search.c 86055 C ~/cvs/emacs/src/search.c
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% src 20959 Dired by name ~/cvs/emacs/src/
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* *mail* 42 Mail
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% HELLO 1607 Fundamental ~/cvs/emacs/etc/HELLO
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% NEWS 481184 Outline ~/cvs/emacs/etc/NEWS
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*scratch* 191 Lisp Interaction
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* *Messages* 1554 Fundamental
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@end smallexample
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@noindent
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Note that the buffer @samp{*Help*} was made by a help request; it is
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not visiting any file. The buffer @code{src} was made by Dired on the
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directory @file{~/cvs/emacs/src/}. You can list only buffers that are
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visiting files by giving the command a prefix argument, as in
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@kbd{C-u C-x C-b}.
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@code{list-buffers} omits buffers whose names begin with a space,
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unless they visit files: such buffers are used internally by Emacs.
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@need 2000
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@node Misc Buffer
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@section Miscellaneous Buffer Operations
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@table @kbd
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@item C-x C-q
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Toggle read-only status of buffer (@code{toggle-read-only}).
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@item M-x rename-buffer @key{RET} @var{name} @key{RET}
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Change the name of the current buffer.
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@item M-x rename-uniquely
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Rename the current buffer by adding @samp{<@var{number}>} to the end.
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@item M-x view-buffer @key{RET} @var{buffer} @key{RET}
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Scroll through buffer @var{buffer}.
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@end table
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@kindex C-x C-q
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@vindex buffer-read-only
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@cindex read-only buffer
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A buffer can be @dfn{read-only}, which means that commands to change
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its contents are not allowed. The mode line indicates read-only
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buffers with @samp{%%} or @samp{%*} near the left margin. Read-only
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buffers are usually made by subsystems such as Dired and Rmail that
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have special commands to operate on the text; also by visiting a file
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whose access control says you cannot write it.
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@findex toggle-read-only
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If you wish to make changes in a read-only buffer, use the command
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@kbd{C-x C-q} (@code{toggle-read-only}). It makes a read-only buffer
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writable, and makes a writable buffer read-only. This
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works by setting the variable @code{buffer-read-only}, which has a local
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value in each buffer and makes the buffer read-only if its value is
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non-@code{nil}. If you have files under version control, you may find
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it convenient to bind @kbd{C-x C-q} to @code{vc-toggle-read-only}
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instead. Then, typing @kbd{C-x C-q} not only changes the read-only
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flag, but it also checks the file in or out. @xref{Version
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Control}.
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@findex rename-buffer
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@kbd{M-x rename-buffer} changes the name of the current buffer. You
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specify the new name as a minibuffer argument; there is no default.
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If you specify a name that is in use for some other buffer, an error
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happens and no renaming is done.
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@findex rename-uniquely
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@kbd{M-x rename-uniquely} renames the current buffer to a similar
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name with a numeric suffix added to make it both different and unique.
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This command does not need an argument. It is useful for creating
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multiple shell buffers: if you rename the @samp{*shell*} buffer, then
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do @kbd{M-x shell} again, it makes a new shell buffer named
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@samp{*shell*}; meanwhile, the old shell buffer continues to exist
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under its new name. This method is also good for mail buffers,
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compilation buffers, and most Emacs features that create special
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buffers with particular names. (With some of these features, such as
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@kbd{M-x compile}, @kbd{M-x grep} an @kbd{M-x info}, you need to
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switch to some other buffer before using the command, in order for it
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to make a different buffer.)
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@findex view-buffer
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@kbd{M-x view-buffer} is much like @kbd{M-x view-file} (@pxref{Misc
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File Ops}) except that it examines an already existing Emacs buffer.
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View mode provides commands for scrolling through the buffer
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conveniently but not for changing it. When you exit View mode with
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@kbd{q}, that switches back to the buffer (and the position) which was
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previously displayed in the window. Alternatively, if you exit View
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mode with @kbd{e}, the buffer and the value of point that resulted from
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your perusal remain in effect.
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The commands @kbd{M-x append-to-buffer} and @kbd{M-x insert-buffer}
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can be used to copy text from one buffer to another. @xref{Accumulating
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Text}.
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@node Kill Buffer
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@section Killing Buffers
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@cindex killing buffers
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If you continue an Emacs session for a while, you may accumulate a
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large number of buffers. You may then find it convenient to @dfn{kill}
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the buffers you no longer need. On most operating systems, killing a
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buffer releases its space back to the operating system so that other
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programs can use it. Here are some commands for killing buffers:
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@table @kbd
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@item C-x k @var{bufname} @key{RET}
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Kill buffer @var{bufname} (@code{kill-buffer}).
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@item M-x kill-some-buffers
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Offer to kill each buffer, one by one.
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@end table
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@findex kill-buffer
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@findex kill-some-buffers
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@kindex C-x k
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@kbd{C-x k} (@code{kill-buffer}) kills one buffer, whose name you
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specify in the minibuffer. The default, used if you type just
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@key{RET} in the minibuffer, is to kill the current buffer. If you
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kill the current buffer, another buffer becomes current: one that was
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current in the recent past but is not displayed in any window now. If
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you ask to kill a file-visiting buffer that is modified (has unsaved
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editing), then you must confirm with @kbd{yes} before the buffer is
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killed.
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The command @kbd{M-x kill-some-buffers} asks about each buffer, one by
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one. An answer of @kbd{y} means to kill the buffer. Killing the current
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buffer or a buffer containing unsaved changes selects a new buffer or asks
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for confirmation just like @code{kill-buffer}.
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The buffer menu feature (@pxref{Several Buffers}) is also convenient
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for killing various buffers.
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@vindex kill-buffer-hook
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If you want to do something special every time a buffer is killed, you
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can add hook functions to the hook @code{kill-buffer-hook} (@pxref{Hooks}).
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@findex clean-buffer-list
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If you run one Emacs session for a period of days, as many people do,
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it can fill up with buffers that you used several days ago. The command
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@kbd{M-x clean-buffer-list} is a convenient way to purge them; it kills
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all the unmodified buffers that you have not used for a long time. An
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ordinary buffer is killed if it has not been displayed for three days;
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however, you can specify certain buffers that should never be killed
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automatically, and others that should be killed if they have been unused
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for a mere hour.
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@cindex Midnight mode
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@vindex midnight-mode
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@vindex midnight-hook
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You can also have this buffer purging done for you, every day at
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midnight, by enabling Midnight mode. Midnight mode operates each day at
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midnight; at that time, it runs @code{clean-buffer-list}, or whichever
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functions you have placed in the normal hook @code{midnight-hook}
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(@pxref{Hooks}).
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To enable Midnight mode, use the Customization buffer to set the
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variable @code{midnight-mode} to @code{t}. @xref{Easy Customization}.
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@node Several Buffers
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@section Operating on Several Buffers
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@cindex buffer menu
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The @dfn{buffer-menu} facility is like a ``Dired for buffers''; it allows
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you to request operations on various Emacs buffers by editing an Emacs
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buffer containing a list of them. You can save buffers, kill them
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(here called @dfn{deleting} them, for consistency with Dired), or display
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them.
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@table @kbd
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@item M-x buffer-menu
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Begin editing a buffer listing all Emacs buffers.
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@item M-x buffer-menu-other-window.
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Similar, but do it in another window.
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@end table
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@findex buffer-menu
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@findex buffer-menu-other-window
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The command @code{buffer-menu} writes a list of all Emacs
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buffers@footnote{Buffers which don't visit files and whose names begin
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with a space are omitted: these are used internally by Emacs.} into the
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buffer @samp{*Buffer List*}, and selects that buffer in Buffer Menu
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mode.
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The buffer is read-only, and can be
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changed only through the special commands described in this section.
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The usual Emacs cursor motion commands can be used in the @samp{*Buffer
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List*} buffer. The following commands apply to the buffer described on
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the current line.
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@table @kbd
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@item d
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Request to delete (kill) the buffer, then move down. The request
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shows as a @samp{D} on the line, before the buffer name. Requested
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deletions take place when you type the @kbd{x} command.
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@item C-d
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Like @kbd{d} but move up afterwards instead of down.
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@item s
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Request to save the buffer. The request shows as an @samp{S} on the
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line. Requested saves take place when you type the @kbd{x} command.
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You may request both saving and deletion for the same buffer.
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@item x
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Perform previously requested deletions and saves.
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@item u
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Remove any request made for the current line, and move down.
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@item @key{DEL}
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Move to previous line and remove any request made for that line.
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@end table
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The @kbd{d}, @kbd{C-d}, @kbd{s} and @kbd{u} commands to add or remove
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flags also move down (or up) one line. They accept a numeric argument
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as a repeat count.
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These commands operate immediately on the buffer listed on the current
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line:
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@table @kbd
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@item ~
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Mark the buffer ``unmodified.'' The command @kbd{~} does this
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immediately when you type it.
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@item %
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Toggle the buffer's read-only flag. The command @kbd{%} does
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this immediately when you type it.
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@item t
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Visit the buffer as a tags table. @xref{Select Tags Table}.
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@end table
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There are also commands to select another buffer or buffers:
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@table @kbd
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@item q
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Quit the buffer menu---immediately display the most recent formerly
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visible buffer in its place.
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@item @key{RET}
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@itemx f
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Immediately select this line's buffer in place of the @samp{*Buffer
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List*} buffer.
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@item o
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Immediately select this line's buffer in another window as if by
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@kbd{C-x 4 b}, leaving @samp{*Buffer List*} visible.
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@item C-o
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Immediately display this line's buffer in another window, but don't
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select the window.
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@item 1
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Immediately select this line's buffer in a full-screen window.
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@item 2
|
|
Immediately set up two windows, with this line's buffer selected in
|
|
one, and the previously current buffer (aside from the buffer
|
|
@samp{*Buffer List*}) displayed in the other.
|
|
@item b
|
|
Bury the buffer listed on this line.
|
|
@item m
|
|
Mark this line's buffer to be displayed in another window if you exit
|
|
with the @kbd{v} command. The request shows as a @samp{>} at the
|
|
beginning of the line. (A single buffer may not have both a delete
|
|
request and a display request.)
|
|
@item v
|
|
Immediately select this line's buffer, and also display in other windows
|
|
any buffers previously marked with the @kbd{m} command. If you have not
|
|
marked any buffers, this command is equivalent to @kbd{1}.
|
|
@end table
|
|
|
|
There is also a command that affects the entire buffer list:
|
|
|
|
@table @kbd
|
|
@item T
|
|
Delete, or reinsert, lines for non-file buffers. This command toggles
|
|
the inclusion of such buffers in the buffer list.
|
|
@end table
|
|
|
|
What @code{buffer-menu} actually does is create and switch to a
|
|
suitable buffer, and turn on Buffer Menu mode in it. Everything else
|
|
described above is implemented by the special commands provided in
|
|
Buffer Menu mode. One consequence of this is that you can switch from
|
|
the @samp{*Buffer List*} buffer to another Emacs buffer, and edit
|
|
there. You can reselect the @samp{*Buffer List*} buffer later, to
|
|
perform the operations already requested, or you can kill it, or pay
|
|
no further attention to it.
|
|
|
|
The list in the @samp{*Buffer List*} buffer looks exactly like the
|
|
buffer list described in @ref{List Buffers}, because they really are
|
|
the same. The only difference between @code{buffer-menu} and
|
|
@code{list-buffers} is that @code{buffer-menu} switches to the
|
|
@samp{*Buffer List*} buffer in the selected window;
|
|
@code{list-buffers} displays the same buffer in another window. If
|
|
you run @code{list-buffers} (that is, type @kbd{C-x C-b}) and select
|
|
the buffer list manually, you can use all of the commands described
|
|
here.
|
|
|
|
Normally, the buffer @samp{*Buffer List*} is not updated
|
|
automatically when buffers are created and killed; its contents are
|
|
just text. If you have created, deleted or renamed buffers, the way
|
|
to update @samp{*Buffer List*} to show what you have done is to type
|
|
@kbd{g} (@code{revert-buffer}). You can make this happen regularly
|
|
every @code{auto-revert-interval} seconds if you enable Auto Revert
|
|
mode in this buffer, as long as it is not marked modified. Global
|
|
Auto Revert mode applies to the @samp{*Buffer List*} buffer only if
|
|
@code{global-auto-revert-non-file-buffers} is non-@code{nil}.
|
|
@inforef{Autorevert,, emacs-xtra}, for details.
|
|
|
|
The command @code{buffer-menu-other-window} works the same as
|
|
@code{buffer-menu}, except that it displays the buffers list in
|
|
another window.
|
|
|
|
@node Indirect Buffers
|
|
@section Indirect Buffers
|
|
@cindex indirect buffer
|
|
@cindex base buffer
|
|
|
|
An @dfn{indirect buffer} shares the text of some other buffer, which
|
|
is called the @dfn{base buffer} of the indirect buffer. In some ways it
|
|
is the analogue, for buffers, of a symbolic link between files.
|
|
|
|
@table @kbd
|
|
@findex make-indirect-buffer
|
|
@item M-x make-indirect-buffer @key{RET} @var{base-buffer} @key{RET} @var{indirect-name} @key{RET}
|
|
Create an indirect buffer named @var{indirect-name} whose base buffer
|
|
is @var{base-buffer}.
|
|
@findex clone-indirect-buffer
|
|
@item M-x clone-indirect-buffer @key{RET}
|
|
Create an indirect buffer that is a twin copy of the current buffer.
|
|
@item C-x 4 c
|
|
@kindex C-x 4 c
|
|
@findex clone-indirect-buffer-other-window
|
|
Create an indirect buffer that is a twin copy of the current buffer, and
|
|
select it in another window (@code{clone-indirect-buffer-other-window}).
|
|
@end table
|
|
|
|
The text of the indirect buffer is always identical to the text of its
|
|
base buffer; changes made by editing either one are visible immediately
|
|
in the other. But in all other respects, the indirect buffer and its
|
|
base buffer are completely separate. They have different names,
|
|
different values of point, different narrowing, different markers,
|
|
different major modes, and different local variables.
|
|
|
|
An indirect buffer cannot visit a file, but its base buffer can. If
|
|
you try to save the indirect buffer, that actually works by saving the
|
|
base buffer. Killing the base buffer effectively kills the indirect
|
|
buffer, but killing an indirect buffer has no effect on its base buffer.
|
|
|
|
One way to use indirect buffers is to display multiple views of an
|
|
outline. @xref{Outline Views}.
|
|
|
|
A quick and handy way to make an indirect buffer is with the command
|
|
@kbd{M-x clone-indirect-buffer}. It creates and selects an indirect
|
|
buffer whose base buffer is the current buffer. With a numeric
|
|
argument, it prompts for the name of the indirect buffer; otherwise it
|
|
uses the name of the current buffer, with a @samp{<@var{n}>} suffix
|
|
added. @kbd{C-x 4 c} (@code{clone-indirect-buffer-other-window})
|
|
works like @kbd{M-x clone-indirect-buffer}, but it selects the new
|
|
buffer in another window.
|
|
|
|
The more general way to make an indirect buffer is with the command
|
|
@kbd{M-x make-indirect-buffer}. It creates an indirect buffer from
|
|
buffer @var{base-buffer}, under the name @var{indirect-name}. It
|
|
prompts for both @var{base-buffer} and @var{indirect-name} using the
|
|
minibuffer.
|
|
|
|
@node Buffer Convenience
|
|
@section Convenience Features and Customization of Buffer Handling
|
|
|
|
This section describes several modes and features that make it more
|
|
convenient to switch between buffers.
|
|
|
|
@menu
|
|
* Uniquify:: Making buffer names unique with directory parts.
|
|
* Iswitchb:: Switching between buffers with substrings.
|
|
* Buffer Menus:: Configurable buffer menu.
|
|
@end menu
|
|
|
|
@node Uniquify
|
|
@subsection Making Buffer Names Unique
|
|
|
|
@cindex unique buffer names
|
|
@cindex directories in buffer names
|
|
When several buffers visit identically-named files, Emacs must give
|
|
the buffers distinct names. The usual method for making buffer names
|
|
unique adds @samp{<2>}, @samp{<3>}, etc. to the end of the buffer
|
|
names (all but one of them).
|
|
|
|
@vindex uniquify-buffer-name-style
|
|
Other methods work by adding parts of each file's directory to the
|
|
buffer name. To select one, customize the variable
|
|
@code{uniquify-buffer-name-style} (@pxref{Easy Customization}).
|
|
|
|
For instance, the @code{forward} naming method puts part of the
|
|
directory name at the beginning of the buffer name; using this method,
|
|
buffers visiting @file{/u/mernst/tmp/Makefile} and
|
|
@file{/usr/projects/zaphod/Makefile} would be named
|
|
@samp{tmp/Makefile} and @samp{zaphod/Makefile}, respectively (instead
|
|
of @samp{Makefile} and @samp{Makefile<2>}).
|
|
|
|
By contrast, the @code{post-forward} naming method would call the
|
|
buffers @samp{Makefile|tmp} and @samp{Makefile|zaphod}, and the
|
|
@code{reverse} naming method would call them @samp{Makefile\tmp} and
|
|
@samp{Makefile\zaphod}. The nontrivial difference between
|
|
@code{post-forward} and @code{reverse} occurs when just one directory
|
|
name is not enough to distinguish two files; then @code{reverse} puts
|
|
the directory names in reverse order, so that @file{/top/middle/file}
|
|
becomes @samp{file\middle\top}, while @code{post-forward} puts them in
|
|
forward order after the file name, as in @samp{file|top/middle}.
|
|
|
|
Which rule to follow for putting the directory names in the buffer
|
|
name is not very important if you are going to @emph{look} at the
|
|
buffer names before you type one. But as an experienced user, if you
|
|
know the rule, you won't have to look. And then you may find that one
|
|
rule or another is easier for you to remember and apply quickly.
|
|
|
|
@node Iswitchb
|
|
@subsection Switching Between Buffers using Substrings
|
|
|
|
@findex iswitchb-mode
|
|
@cindex Iswitchb mode
|
|
@cindex mode, Iswitchb
|
|
@kindex C-x b @r{(Iswitchb mode)}
|
|
@kindex C-x 4 b @r{(Iswitchb mode)}
|
|
@kindex C-x 5 b @r{(Iswitchb mode)}
|
|
@kindex C-x 4 C-o @r{(Iswitchb mode)}
|
|
|
|
Iswitchb global minor mode provides convenient switching between
|
|
buffers using substrings of their names. It replaces the normal
|
|
definitions of @kbd{C-x b}, @kbd{C-x 4 b}, @kbd{C-x 5 b}, and @kbd{C-x
|
|
4 C-o} with alternative commands that are somewhat ``smarter.''
|
|
|
|
When one of these commands prompts you for a buffer name, you can
|
|
type in just a substring of the name you want to choose. As you enter
|
|
the substring, Iswitchb mode continuously displays a list of buffers
|
|
that match the substring you have typed.
|
|
|
|
At any time, you can type @key{RET} to select the first buffer in
|
|
the list. So the way to select a particular buffer is to make it the
|
|
first in the list. There are two ways to do this. You can type more
|
|
of the buffer name and thus narrow down the list, excluding unwanted
|
|
buffers above the desired one. Alternatively, you can use @kbd{C-s}
|
|
and @kbd{C-r} to rotate the list until the desired buffer is first.
|
|
|
|
@key{TAB} while entering the buffer name performs completion on the
|
|
string you have entered, based on the displayed list of buffers.
|
|
|
|
To enable Iswitchb mode, type @kbd{M-x iswitchb-mode}, or customize
|
|
the variable @code{iswitchb-mode} to @code{t} (@pxref{Easy
|
|
Customization}).
|
|
|
|
@node Buffer Menus
|
|
@subsection Customizing Buffer Menus
|
|
|
|
@findex bs-show
|
|
@cindex buffer list, customizable
|
|
@table @kbd
|
|
@item M-x bs-show
|
|
Make a list of buffers similarly to @kbd{M-x list-buffers} but
|
|
customizable.
|
|
@end table
|
|
|
|
@kbd{M-x bs-show} pops up a buffer list similar to the one normally
|
|
displayed by @kbd{C-x C-b} but which you can customize. If you prefer
|
|
this to the usual buffer list, you can bind this command to @kbd{C-x
|
|
C-b}. To customize this buffer list, use the @code{bs} Custom group
|
|
(@pxref{Easy Customization}).
|
|
|
|
@findex msb-mode
|
|
@cindex mode, MSB
|
|
@cindex MSB mode
|
|
@cindex buffer menu
|
|
@findex mouse-buffer-menu
|
|
@kindex C-Down-Mouse-1
|
|
MSB global minor mode (``MSB'' stands for ``mouse select buffer'')
|
|
provides a different and customizable mouse buffer menu which you may
|
|
prefer. It replaces the bindings of @code{mouse-buffer-menu},
|
|
normally on @kbd{C-Down-Mouse-1}, and the menu bar buffer menu. You
|
|
can customize the menu in the @code{msb} Custom group.
|
|
|
|
@ignore
|
|
arch-tag: 08c43460-f4f4-4b43-9cb5-1ea9ad991695
|
|
@end ignore
|