@samp{*mail*} is used to hold the text of the message. When you ask for a
command's documentation, that appears in a buffer called @samp{*Help*}.
+ Each buffer has a unique name, which can be of any length. When a
+buffer is displayed in a window, its name is shown in the mode line
+(@pxref{Mode Line}). The distinction between upper and lower case
+matters in buffer names. Most buffers are made by visiting files, and
+their names are derived from the files' names; however, you can also
+create an empty buffer with any name you want. A newly started Emacs
+has a buffer named @samp{*scratch*}, which is not associated with any
+file and can be used for evaluating Lisp expressions in Emacs
+(@pxref{Lisp Interaction}).
+
@cindex selected buffer
@cindex current buffer
- At any time, one and only one buffer is @dfn{current}. It is also
-called the @dfn{selected buffer}. Often we say that a command operates on
-``the buffer'' as if there were only one; but really this means that the
-command operates on the current buffer (most commands do).
-
- When Emacs has multiple windows, each window has its own chosen
-buffer and displays it; at any time, only one of the windows is
-selected, and its chosen buffer is the current buffer. Each window's
-mode line normally displays the name of the window's chosen buffer
-(@pxref{Windows}).
-
- Each buffer has a name, which can be of any length, and you can select
-any buffer by giving its name. Most buffers are made by visiting files,
-and their names are derived from the files' names. But you can also create
-an empty buffer with any name you want. A newly started Emacs has a buffer
-named @samp{*scratch*} which can be used for evaluating Lisp expressions in
-Emacs. The distinction between upper and lower case matters in buffer
-names.
-
- Each buffer records individually what file it is visiting, whether it is
-modified, and what major mode and minor modes are in effect in it
-(@pxref{Major Modes}). Any Emacs variable can be made @dfn{local to} a
-particular buffer, meaning its value in that buffer can be different from
-the value in other buffers. @xref{Locals}.
+ At any time, one and only one buffer is @dfn{current}. This is also
+called the @dfn{selected buffer}. We often say that a command
+operates on ``the buffer''; this really means that the command
+operates on the current buffer (most commands do). When there is only
+one Emacs window, the buffer displayed in that window is current.
+When there are multiple windows present, the buffer displayed in the
+@dfn{selected window} is current. @xref{Windows}.
+
+ Each buffer records individually what file it is visiting (if any),
+whether it is modified, and what major mode and minor modes are in
+effect (@pxref{Major Modes}). Any Emacs variable can be made
+@dfn{local to} a particular buffer, meaning its value in that buffer
+can be different from the value in other buffers. @xref{Locals}.
@cindex buffer size, maximum
A buffer's size cannot be larger than some maximum, which is defined
@kindex C-x b
@findex switch-to-buffer
- To select the buffer named @var{bufname}, type @kbd{C-x b @var{bufname}
-@key{RET}}. This runs the command @code{switch-to-buffer} with argument
-@var{bufname}. You can use completion to enter the buffer
-name (@pxref{Completion}). An empty argument to @kbd{C-x b}
-specifies the buffer that was current most recently among those not
+ To select the buffer named @var{bufname}, type @kbd{C-x b
+@var{bufname} @key{RET}}. This runs the command
+@code{switch-to-buffer} with argument @var{bufname}. While entering
+the buffer name, you can use the usual minibuffer completion and
+history commands (@pxref{Minibuffer}). An empty argument to @kbd{C-x
+b} specifies the buffer that was current most recently among those not
now displayed in any window.
+ If you specify a buffer that does not exist, @kbd{C-x b} creates a
+new, empty buffer that is not visiting any file, and selects it for
+editing. You can use such a buffer for making temporary notes. If
+you try to save it, you are asked for the file name to use. The new
+buffer's major mode is determined by the variable
+@code{default-major-mode}; the default value is Fundamental mode.
+@xref{Major Modes}.
+
@kindex C-x @key{LEFT}
@kindex C-x @key{RIGHT}
@findex next-buffer
@findex switch-to-buffer-other-window
@vindex even-window-heights
To select a buffer in a window other than the current one, type
-@kbd{C-x 4 b @var{bufname} @key{RET}}. This runs the command
-@code{switch-to-buffer-other-window} which displays the buffer
-@var{bufname} in another window. By default, if displaying the buffer
-causes two vertically adjacent windows to be displayed, the heights of
-those windows are evened out; to countermand that and preserve the
-window configuration, set the variable @code{even-window-heights} to
-@code{nil}.
+@kbd{C-x 4 b} (@code{switch-to-buffer-other-window}). This prompts
+for a buffer name using the minibuffer, displays that buffer in
+another window, and selects that window. By default, if displaying
+the buffer causes two vertically adjacent windows to be displayed, the
+heights of those windows are evened out; to countermand that and
+preserve the window configuration, set the variable
+@code{even-window-heights} to @code{nil}.
@kindex C-x 5 b
@findex switch-to-buffer-other-frame
- Similarly, @kbd{C-x 5 b @var{buffer} @key{RET}} runs the command
-@code{switch-to-buffer-other-frame} which selects a buffer in another
-frame.
+ Similarly, @kbd{C-x 5 b} (@code{switch-to-buffer-other-frame})
+prompts for a buffer name, displays that buffer in another frame, and
+selects that frame.
+
+ In addition, @kbd{C-x C-f}, and any other command for visiting a
+file, can also be used to switch to an existing file-visiting buffer.
+@xref{Visiting}.
@vindex display-buffer-reuse-frames
You can control how certain buffers are handled by these commands by
non-@code{nil}, and the buffer you want to switch to is already
displayed in some frame, Emacs will just raise that frame.
- Most buffers are created by visiting files, or by Emacs commands that
-want to display some text, but you can also create a buffer explicitly
-by typing @kbd{C-x b @var{bufname} @key{RET}}. This makes a new, empty
-buffer that is not visiting any file, and selects it for editing. Such
-buffers are used for making notes to yourself. If you try to save one,
-you are asked for the file name to use. The new buffer's major mode is
-determined by the value of @code{default-major-mode} (@pxref{Major
-Modes}).
-
- Note that @kbd{C-x C-f}, and any other command for visiting a file,
-can also be used to switch to an existing file-visiting buffer.
-@xref{Visiting}.
-
- @kbd{C-u M-g M-g}, that is @code{goto-line} with a prefix argument
-of just @kbd{C-u}, reads a number @var{n} using the minibuffer,
-selects the most recently selected buffer other than the current
-buffer in another window, and then moves point to the beginning of
-line number @var{n} in that buffer. This is mainly useful in a buffer
-that refers to line numbers in another buffer: if point is on or just
-after a number, @code{goto-line} uses that number as the default for
-@var{n}. Note that prefix arguments other than just @kbd{C-u} behave
-differently. @kbd{C-u 4 M-g M-g} goes to line 4 in the @emph{current}
-buffer, without reading a number from the minibuffer. (Remember that
-@kbd{M-g M-g} without prefix argument reads a number @var{n} and then
-moves to line number @var{n} in the current buffer.)
+ @kbd{C-u M-g M-g}, that is @code{goto-line} with a plain prefix
+argument, reads a number @var{n} using the minibuffer, selects the
+most recently selected buffer other than the current buffer in another
+window, and then moves point to the beginning of line number @var{n}
+in that buffer. This is mainly useful in a buffer that refers to line
+numbers in another buffer: if point is on or just after a number,
+@code{goto-line} uses that number as the default for @var{n}. Note
+that prefix arguments other than just @kbd{C-u} behave differently.
+@kbd{C-u 4 M-g M-g} goes to line 4 in the @emph{current} buffer,
+without reading a number from the minibuffer. (Remember that @kbd{M-g
+M-g} without prefix argument reads a number @var{n} and then moves to
+line number @var{n} in the current buffer. @xref{Moving Point}.)
Emacs uses buffer names that start with a space for internal purposes.
It treats these buffers specially in minor ways---for example, by
The buffers are listed in the order that they were current; the
buffers that were current most recently come first.
- @samp{*} in the first field of a line indicates the buffer is
-``modified.'' If several buffers are modified, it may be time to save
-some with @kbd{C-x s} (@pxref{Save Commands}). @samp{%} indicates a
-read-only buffer. @samp{.} marks the current buffer. Here is an
-example of a buffer list:@refill
+ @samp{.} in the first field of a line indicates that the buffer is
+current. @samp{%} indicates a read-only buffer. @samp{*} indicates
+that the buffer is ``modified.'' If several buffers are modified, it
+may be time to save some with @kbd{C-x s} (@pxref{Save Commands}).
+Here is an example of a buffer list:
@smallexample
CRM Buffer Size Mode File
@end smallexample
@noindent
-Note that the buffer @samp{*Help*} was made by a help request; it is
-not visiting any file. The buffer @code{src} was made by Dired on the
-directory @file{~/cvs/emacs/src/}. You can list only buffers that are
-visiting files by giving the command a prefix argument, as in
+The buffer @samp{*Help*} was made by a help request (@pxref{Help}); it
+is not visiting any file. The buffer @code{src} was made by Dired on
+the directory @file{~/cvs/emacs/src/}. You can list only buffers that
+are visiting files by giving the command a prefix argument, as in
@kbd{C-u C-x C-b}.
@code{list-buffers} omits buffers whose names begin with a space,
unless they visit files: such buffers are used internally by Emacs.
-@need 2000
@node Misc Buffer
@section Miscellaneous Buffer Operations
Kill buffer @var{bufname} (@code{kill-buffer}).
@item M-x kill-some-buffers
Offer to kill each buffer, one by one.
+@item M-x kill-matching-buffers
+Offer to kill all buffers matching a regular expression.
@end table
@findex kill-buffer
-@findex kill-some-buffers
@kindex C-x k
-
@kbd{C-x k} (@code{kill-buffer}) kills one buffer, whose name you
specify in the minibuffer. The default, used if you type just
@key{RET} in the minibuffer, is to kill the current buffer. If you
kill the current buffer, another buffer becomes current: one that was
current in the recent past but is not displayed in any window now. If
-you ask to kill a file-visiting buffer that is modified (has unsaved
-editing), then you must confirm with @kbd{yes} before the buffer is
-killed.
-
- The command @kbd{M-x kill-some-buffers} asks about each buffer, one by
-one. An answer of @kbd{y} means to kill the buffer. Killing the current
-buffer or a buffer containing unsaved changes selects a new buffer or asks
-for confirmation just like @code{kill-buffer}.
+you ask to kill a file-visiting buffer that is modified, then you must
+confirm with @kbd{yes} before the buffer is killed.
- The buffer menu feature (@pxref{Several Buffers}) is also convenient
-for killing various buffers.
+@findex kill-some-buffers
+ The command @kbd{M-x kill-some-buffers} asks about each buffer, one
+by one. An answer of @kbd{y} means to kill the buffer, just like
+@code{kill-buffer}. This command ignores buffers whose names begin
+with a space, which are used internally by Emacs.
+
+@findex kill-matching-buffers
+ The command @kbd{M-x kill-matching-buffers} prompts for a regular
+expression and kills all buffers whose names match that expression.
+@xref{Regexps}. Like @code{kill-some-buffers}, it asks for
+confirmation before each kill. This command normally ignores buffers
+whose names begin with a space, which are used internally by Emacs.
+To kill internal buffers as well, call @code{kill-matching-buffers}
+with a prefix argument.
+
+ The buffer menu feature is also convenient for killing various
+buffers. @xref{Several Buffers}.
@vindex kill-buffer-hook
If you want to do something special every time a buffer is killed, you
@vindex midnight-mode
@vindex midnight-hook
You can also have this buffer purging done for you, every day at
-midnight, by enabling Midnight mode. Midnight mode operates each day at
-midnight; at that time, it runs @code{clean-buffer-list}, or whichever
-functions you have placed in the normal hook @code{midnight-hook}
-(@pxref{Hooks}).
-
- To enable Midnight mode, use the Customization buffer to set the
-variable @code{midnight-mode} to @code{t}. @xref{Easy Customization}.
+midnight, by enabling Midnight mode. Midnight mode operates each day
+at midnight; at that time, it runs @code{clean-buffer-list}, or
+whichever functions you have placed in the normal hook
+@code{midnight-hook} (@pxref{Hooks}). To enable Midnight mode, use
+the Customization buffer to set the variable @code{midnight-mode} to
+@code{t}. @xref{Easy Customization}.
@node Several Buffers
@section Operating on Several Buffers
@cindex buffer menu
- The @dfn{buffer-menu} facility is like a ``Dired for buffers''; it allows
-you to request operations on various Emacs buffers by editing an Emacs
-buffer containing a list of them. You can save buffers, kill them
-(here called @dfn{deleting} them, for consistency with Dired), or display
-them.
-
@table @kbd
@item M-x buffer-menu
Begin editing a buffer listing all Emacs buffers.
Similar, but do it in another window.
@end table
+ The @dfn{buffer menu} opened by @kbd{C-x C-b} (@pxref{List Buffers})
+does not merely list buffers. It also allows you to perform various
+operations on buffers, through an interface similar to Dired
+(@pxref{Dired}). You can save buffers, kill them (here called
+@dfn{deleting} them, for consistency with Dired), or display them.
+
@findex buffer-menu
@findex buffer-menu-other-window
- The command @code{buffer-menu} writes a list of all Emacs
-buffers@footnote{Buffers which don't visit files and whose names begin
-with a space are omitted: these are used internally by Emacs.} into the
-buffer @samp{*Buffer List*}, and selects that buffer in Buffer Menu
-mode.
-
- The buffer is read-only, and can be
-changed only through the special commands described in this section.
-The usual Emacs cursor motion commands can be used in the @samp{*Buffer
-List*} buffer. The following commands apply to the buffer described on
-the current line.
+ To use the buffer menu, type @kbd{C-x C-b} and switch to the window
+displaying the @samp{*Buffer List*} buffer. You can also type
+@kbd{M-x buffer-menu} to open the buffer menu in the selected window.
+Alternatively, the command @kbd{M-x buffer-menu-other-window} opens
+the buffer menu in another window, and selects that window.
+
+ The buffer menu is a read-only buffer, and can be changed only
+through the special commands described in this section. The usual
+Emacs cursor motion commands can be used in this buffer. The
+following commands apply to the buffer described on the current line:
@table @kbd
@item d
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
@xref{Autorevert, global-auto-revert-non-file-buffers}, for details.
@end ifnottex
-
- 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
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,
+base buffer are completely separate. They can have different names,
different values of point, different narrowing, different markers,
different major modes, and different local variables.
One way to use indirect buffers is to display multiple views of an
outline. @xref{Outline Views}.
+@vindex clone-indirect-buffer-hook
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
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.
+buffer in another window. These functions run the hook
+@code{clone-indirect-buffer-hook} after creating the indirect buffer.
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
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