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Table of Contents

Chapter 1: GNU Emacs Pocket Reference

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Emacs is a powerful text editor and, unlike most editors, it is a complete working environment. GNU Emacs is the most popular and widespread of the Emacs family of editors. Covering GNU Emacs 20.2, this small book has condensed Emacs reference material and provides a resource for readers of O'Reilly & Associates' Learning GNU Emacs, by Debra Cameron, Bill Rosenblatt, and Eric Raymond.

Emacs commands consist of a modifier, such as CTRL (CONTROL) or ESC (ESCAPE), followed by one or two characters. Commands shown in this book abbreviate CTRL to C:

C-g

Hold down the CTRL key and press g.

Most Emacs manuals refer to the META key in addition to the CTRL key. Since most keyboards don't have a META key, this book refers to ESC instead of META:

ESC x

Press ESC, release it, then press x.

It is entirely possible that your keyboard has a META key. On many keyboards, the ALT keys function as the META key. If your keyboard does have a META key, it works like the CTRL key described here—that is, you hold down the META key and press the desired key, such as g.

UNIX commands, Emacs keystrokes, command names, menu options, and variables are shown in boldface type.

Filenames are shown in italic type.

Buffer names, LISP code, C code, Emacs messages, and other excerpts from programs are shown in

constant width

type.

Dummy parameters that you replace with an actual value are shown in italic type. (If they appear within code, they are shown in constant width italic type.)

Emacs achieves some of its famed versatility by having various editing modes in which it behaves slightly differently. The word mode may sound technical or complicated, but what it really means is that Emacs becomes sensitive to the task at hand.

Text mode and C mode are major modes. A buffer can be in only one major mode at a time; to exit a major mode, you have to enter another one.

Section 1.1.1.1: Major modes

Whenever you edit a file, Emacs attempts to put you into the correct major mode. If you edit a file that ends in .c, it puts you into C mode. If you edit a file that ends in

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Introduction

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Emacs is a powerful text editor and, unlike most editors, it is a complete working environment. GNU Emacs is the most popular and widespread of the Emacs family of editors. Covering GNU Emacs 20.2, this small book has condensed Emacs reference material and provides a resource for readers of O'Reilly & Associates' Learning GNU Emacs, by Debra Cameron, Bill Rosenblatt, and Eric Raymond.

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Emacs Commands

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Emacs commands consist of a modifier, such as CTRL (CONTROL) or ESC (ESCAPE), followed by one or two characters. Commands shown in this book abbreviate CTRL to C:

C-g

Hold down the CTRL key and press g.

Most Emacs manuals refer to the META key in addition to the CTRL key. Since most keyboards don't have a META key, this book refers to ESC instead of META:

ESC x

Press ESC, release it, then press x.

It is entirely possible that your keyboard has a META key. On many keyboards, the ALT keys function as the META key. If your keyboard does have a META key, it works like the CTRL key described here—that is, you hold down the META key and press the desired key, such as g.

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Conventions

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UNIX commands, Emacs keystrokes, command names, menu options, and variables are shown in boldface type.

Filenames are shown in italic type.

Buffer names, LISP code, C code, Emacs messages, and other excerpts from programs are shown in

constant width

type.

Dummy parameters that you replace with an actual value are shown in italic type. (If they appear within code, they are shown in constant width italic type.)

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Emacs Basics

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Emacs achieves some of its famed versatility by having various editing modes in which it behaves slightly differently. The word mode may sound technical or complicated, but what it really means is that Emacs becomes sensitive to the task at hand.

Text mode and C mode are major modes. A buffer can be in only one major mode at a time; to exit a major mode, you have to enter another one.

Section 1.1.1.1: Major modes

Whenever you edit a file, Emacs attempts to put you into the correct major mode. If you edit a file that ends in .c, it puts you into C mode. If you edit a file that ends in .el, it puts you in LISP mode.

Major Mode			Function
Fundamental mode			The default mode; no special behavior
Text mode			For writing text
Mail mode			For writing mail messages
RMAIL mode			For reading and organizing mail
View mode			For viewing files but not editing
Shell mode			For running a UNIX shell within Emacs
Telnet mode			For logging in to remote systems
Outline mode			For writing outlines
Indented text mode			For indenting text automatically
Nroff mode			For formatting files for nroff
TeX mode			For formatting files for TeX
LaTeX mode			For formatting files for LaTeX
C mode			For writing C programs
C++ mode			For writing C++ programs
Java mode			For writing Java programs
FORTRAN mode			For writing FORTRAN programs
Emacs LISP mode			For writing Emacs LISP functions
LISP mode			For writing LISP programs
LISP interaction mode			For writing and evaluating LISP expressions

Section 1.1.1.2: Minor modes

In addition to major modes, there are also minor modes. These define a particular aspect of Emacs behavior and can be turned on and off within a major mode.

Minor Mode	Function
Auto-fill mode	Enables word wrap
Overwrite mode	Replaces characters as you type instead of inserting them
Auto-save mode	Saves your file automatically every so often in an auto-save file
Abbrev mode	Allows you to define word abbreviations
Transient mark mode	Highlights selected regions of text
Outline mode	For writing outlines
VC mode	For using various version control systems under Emacs

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Editing Files

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Text mode is the standard mode for typing text. By default, Emacs does not do word wrap, instead creating very long lines. To enable word wrap, type ESC x auto-fill-mode RETURN.

You may decide that you want to enter auto-fill mode automatically whenever you edit. If so, add this line to the Emacs startup file, .emacs, which is located in your home directory. (If the startup file doesn't exist, create it.)

(setq default-major-mode 'text-mode)
(add-hook 'text-mode-hook 'turn-on-auto-fill)

To move	Keystrokes Command Name
Forward one character	C-f forward-char
Backward one character	C-b backward-char
Up one line	C-p previous-line
Down one line (at the end of a file, creates a newline)	C-n next-line
Forward one word	ESC f forward-word
Backward one word	ESC b backward-word
To the beginning of the line	C-a beginning-of-line
To the end of the line	C-e end-of-line
Forward one screen	C-v scroll-up
Backward one screen	ESC v scroll-down
To the beginning of the file	ESC < beginning-of-buffer
To the end of the file	ESC > end-of-buffer

To	Keystrokes Command Name
Repeat the following command n times	ESC n digit-argument
Repeat the following command 4 times	C-u universal-argument
Repeat the following command 16 times	C-u C-u universal-argument
Repeat a complex command (can edit arguments)	C-x ESC ESC repeat-complex- command
Recall previous command in minibuffer	ESC p previous-history-element

Emacs has two distinct concepts when it comes to cutting text. You can delete text, which implies that you want to eliminate it entirely. Or you can kill text, which implies that you want to paste it in another location. Emacs stores killed text in the kill ring. Commands that use the word kill (such as kill-word) store text in the kill ring. Commands that use the word delete (such as delete-char) do not store the text in the kill ring.

To delete	Keystrokes Command Name
Character	C-d delete-char
Previous character	DEL delete-backward-char
Word	ESC d kill-word
Previous word	ESC DEL

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Search and Replace Operations

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An incremental search begins when you type the first letter and continues searching as you add characters.

To	Keystrokes Command Name
Incremental search forward	C-s isearch-forward
Incremental search backward	C-r isearch-backward
Exit incremental search	RETURN
Cancel incremental search	C-g keyboard-quit
Delete incorrect character of search string	DEL

Emacs provides a plain vanilla search, in which you type the whole word, then start the search. It also offers a word search. This search finds whole words and can find phrases spread across line breaks.

To	Keystrokes
Search forward	C-s RETURN
Search backward	C-r RETURN
Word search	C-s RETURN C-w

To	Keystrokes Command Name
Enter query-replace	ESC % query-replace
Replace and go on to the next instance	SPACE or y
Don't replace; move on to next instance	DEL or n
Replace the current instance and quit	.
Replace and pause (SPACE or y to move on)	,
Replace the rest and don't ask	!
Back up to the previous instance	^
Exit query-replace	RETURN or q
Enter recursive edit	C-r
Delete this instance and enter a recursive edit	C-w
Exit recursive edit and resume query-replace	ESC C-c
Exit recursive edit and exit query-replace	C-]

This section lists characters for creating regular expressions, followed by commands for replacement operations using regular expressions.

Section 1.3.4.1: Characters for creating regular expressions

Symbol	Matches
^	The beginning of a line
$	The end of a line
.	Any single character (like ? in filenames)
.*	Any group of zero or more characters (like * in filenames)
\<	The beginning of a word
\>	The end of a word
[]	Any character specified within the brackets; for example, [a-z] matches any alphabetic character

To	Keystrokes Command Name
Search for a regular expression forward	ESC C-s RETURN re-search-forward
Search for a regular expression backward	ESC C-r RETURN re-search-backward
Search incrementally forward for a regular expression	ESC C-s isearch-forward-regexp
Repeat incremental regular expression search

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Using Buffers and Windows

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To	Keystrokes Command Name
Move to the buffer specified	C-x b buffername switch-to-buffer
Display the buffer list	C-x C-b list-buffers
Delete the buffer specified	C-x k buffername kill-buffer
Ask about deleting each buffer	ESC x kill-some-buffers
Change the buffer's name	ESC x rename-buffer
Ask about saving each modified buffer	C-x s save-some-buffers

Section 1.4.1.1: Buffer list commands

To	Keystrokes
Move to the next buffer	SPACE or n
Move to the previous buffer	p
Mark buffer for deletion	d or k
Save buffer	s
Unmark buffer	u
Execute other one-letter commands on all marked buffers	x
Unmark the previous buffer in the list	DEL
Mark buffer as unmodified	~
Toggle read-only status of buffer	%
Display buffer in a full screen	1
Display this buffer and the next one in horizontal windows	2
Replace buffer list with this buffer	f
Replace other window with this buffer	o
Mark buffers to be displayed in windows	m
Display buffers marked with m; Emacs makes as many windows as needed	v
Quit buffer list	q

Windows subdivide the current Emacs window. To create new Emacs windows, see the following section on Frames.

To	Keystrokes Command Name
Create two windows, one on top of the other	C-x 2 split-window-vertically
Move to the other window	C-x o other-window
Delete the current window	C-x 0 delete-window
Delete all windows but this one	C-x 1 delete-other-windows
Make window taller	C-x ^ enlarge-window
Make window shorter	ESC x shrink-window
Scroll other window	ESC C-v scroll-other-window
Find a file in another other window	C-x 4 f find-file-other-window
Delete buffer and window (asks for confirmation)	C-x 4 0 kill-buffer-and-window

Frame commands apply only when Emacs is running under a GUI, such as X Windows.

To	Keystrokes Command Name
Make a new frame	C-x 5 2 make-frame-command
Move to another frame	C-x 5 o other-frame
Delete current frame	C-x 5 0 delete-frame
Find file in a new frame	C-x 5 f find-file-other-frame
Make frame and display other buffer in it	C-x 5 b switch-to-buffer-other- frame

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Emacs as a Work Environment

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Shell mode lets you access the UNIX shell without leaving Emacs. A rule of thumb in shell mode is that you preface all ordinary control sequences with C-c. For example, to interrupt a command, type C-c C-c.

To	Keystrokes Command Name
Enter shell mode	ESC x shell,
Interrupt current job; equivalent to C-c in UNIX shells	C-c C-c comint-interrupt-subjob
Delete a character; if at end of buffer send an EOF character	C-d comint-delchar-or- maybe-eof
Send EOF character	C-c C-d comint-send-eof
Erase current line; C-u> in UNIX shells	C-c C-u comint-kill-input
Suspend or stop a job; C-z in UNIX shells	C-c C-z comint-stop-subjob
Display previous command; repeat to display earlier commands	ESC p comint-previous-input
Display subsequent commands; repeat to display more recent commands	ESC n comint-next-input
Execute command on current line	RETURN comint-send-input
Complete command, filename, or variable name	TAB comint-dynamic- complete
Delete output from last command	C-c C-o comint-kill-output
Move last line of output to bottom of window	C-c C-e comint-show-maximum- output

Dired is Emacs's directory editor. It provides a convenient way to manage files and directories.

To	Keystrokes Command Name
Start Dired	C-x d dired
Copy	C dired-do-copy
Flag for deletion	d dired-flag-file-deletion
Delete immediately	D dired-do-delete
Open file or directory	e or f dired-find-file
Reread the directory from disk	g revert-buffer
Change group permissions	G dired-do-chgrp
Remove line from display (don't delete it)	k dired-do-kill-lines
Mark with *	m dired-mark
Move to the next line	n dired-next-line
Find file in another window; move there	o dired-find-file-other- window
Find file in another window; don't move there	C-o dired-display-file
Print file	P dired-do-print
Quit Dired	q dired-quit
Query-replace string in marked files	Q dired-do-query-replace
Rename file	R dired-do-rename
Unmark file	u dired-unmark
View file	v dired-view-file
Delete files flagged with D	x dired-do-flagged-delete
Compress file	Z dired-do-compress

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Email and Newsgroups

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To	Keystrokes
Compose a mail message	C-x m
Compose a mail message in another window	C-x 4 m
Compose a mail message in another frame	C-x 5 m
Insert contents of the .signature file	C-c C-w
Send message	C-c C-c
Define an alias for a name or a group of names	ESC x define-mail-alias

Emacs interfaces with a number of mail programs, but its own mail program is RMAIL.

To	Keystrokes
Read mail with RMAIL	ESC x rmail
Scroll to the next screen of the message	SPACE
Scroll to the previous screen of this message	DEL
Move to the beginning of this message	.
Move to the next message	n
Move to the previous message	p
Move to the first message	<
Move to the last message	>
Jump to a certain message (preface with the number of the message to jump to)	j
Flag this message for deletion and move forward	d
Flag this message for deletion and move backward	C-d
Undelete a message that has been flagged for deletion	u
Delete all messages flagged for deletion	x
Save message in RMAIL file format	o filename RETURN
Save message as a standard ASCII text file	C-o filename RETURN.
Display a window that lists all messages	h
Exit RMAIL	q

Emacs has a built-in newsreader called Gnus. To enter Gnus, type ESC x gnus. You'll see a group buffer, commands for which are listed below. Select the newsgroup you want to read. Commands for the summary buffer, which lists messages in a given newsgroup, are listed below as well.

Section 1.6.3.1: Gnus group buffer commands

To	Keystrokes
Start Gnus	ESC x gnus
Read articles in the group the cursor is on	SPACE
Subscribe or unsubscribe to this group	u
Prompt for a group to jump to	j
List all newsgroups you subscribe to	l
List groups that have been killed (killed groups are listed in the .newsrc.eld file)	A k
List all newsgroups available on this server	L
Get new news	g
Write a message for this group	a
Exit news and update .newsrc file	q

Section 1.6.3.2: Gnus summary buffer commands

To	Keystrokes
Scroll forward	SPACE
Scroll backward	DEL
Move to the last posting you read	l
Get the FAQ for this newsgroup	H f
Move to the next article

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Emacs and the Internet

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To	Keystrokes Command Name
Start Telnet mode	ESC x telnet
Depending on the context, send EOF or delete the character under the cursor	C-d comint-delchar-or- maybe-eof
Process Telnet input	RETURN telnet-send-input
Interrupt current job; C-c in UNIX shells	C-c C-c telnet-interrupt-subjob
Send the next character quoted; similar to C-q	C-c C-q send-process-next-char
Send EOF character	C-c C-d comint-send-eof
Move first line of output to top of window	C-c C-r comint-show-output
Move last line of output to bottom of window	C-c C-e comint-show-maximum- output
Delete output from last command	C-c C-o comint-kill-output
Suspend or stop a job; C-z in UNIX shells	C-c C-z telnet-c-z
Erase current line; C-u in UNIX shells	C-c C-u comint-kill-input
Retrieve subsequent commands (can be repeated to find more recent commands)	ESC n comint-next-input
Retrieve previous commands (can be repeated to find earlier commands)	ESC p comint-previous-input

Ange-ftp mode alleviates the need for learning FTP commands. Essentially, you "find" files on remote systems using C-x C-f, then copy them using Dired commands (described in Section 5). Ange-ftp mode is a transparent interface to FTP that is included in Emacs.

Emacs starts ange-ftp mode if the following three conditions are met:

1. The filename begins with a slash (/).
2. The slash is followed by username@systemname.
3. 3. There is a colon (:) between the system name and the directory or filenames, if any (for example, /anonymous@rtfm.mit.ed u:/pub).

For example, typing /anonymous@rtfm.mit.edu:/pub opens an FTP connection to rtfm.mit.edu and displays the /pub directory. Don't forget the slash at the beginning or the colon between the system name and the path to the file.

Emacs includes commands for invoking web browsers. The default browser is set to Netscape, but can be changed by setting the variable browse-url-browser-function.

Alternatively, you can download and install a web browser that works from within Emacs, W3 mode, available at ftp://cs.indiana.edu/pub/elisp/w3/w3.tar.gz.

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Simple Text Formatting and Specialized Editing

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Centering commands work only in text mode.

To	Keystrokes Command Name
Center a line	ESC s center-line
Center a paragraph	ESC S center-paragraph
Center a region	ESC x center-region

To insert a page break in a file, type C-q C-l. C-q is the quoted-insert command; it inserts the next control sequence as a control character rather than interpreting it as an Emacs command. You can also search and replace control characters by prefacing the search string with C-q in query-replace.

Rectangle editing is particularly useful for deleting or rearranging columns of data.

To	Keystrokes Command Name
Delete a rectangle and store it	C-x r k kill-rectangle
Delete a rectangle; do not store it	C-x r d delete-rectangle
Insert the last rectangle killed	C-x r y yank-rectangle
Blank out the area marked as a rectangle; do not store it	C-x r c clear-rectangle
Insert a blank rectangle in the area marked	C-x r o open-rectangle

To	Keystrokes Command Name
Move to the next heading	C-c C-n outline-next-visible- heading
Move to the previous heading	C-c C-p outline-previous- visible-heading
Move to the next heading of the same level	C-c C-f outline-forward-same- level
Move to the previous heading of the same level	C-c C-b outline-backward-same- level
Move up one heading level	C-c C-u outline-up-heading
Hide all body lines	C-c C-t hide-body
Hide subheads and bodies associated with a given heading	C-c C-d hide-subtree
Hide the body associated with a particular heading (not subheads and their bodies)	ESC x hide-entry
Hide the body of a particular heading and the bodies of all its subheads	C-c C-l hide-leaves
Show everything that's hidden	C-c C-a show-all

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Marking Up Text with Emacs

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To	Keystrokes Command Name
Enter nroff mode	ESC x nroff-mode
Move the cursor to the next text line	ESC n forward-text-line
Move the cursor to the previous text line	ESC p backward-text-line
Enter electric nroff mode (a minor mode in which you type the first in a pair of nroff commands, then press C-j, and Emacs inserts the second command of the pair)	ESC x electric-nroff-mode
Complete common macro pairs	C-j electric-nroff-newline

To	Keystrokes Command Name
Enter TeXmode	ESC x plain-tex-mode
Enter LaTeX mode	ESC x latex-mode
Insert two hard returns (standard end of paragraph) and check syntax of paragraph	C-j tex-terminate-paragraph
Insert two braces and put cursor between them	C-c { tex-insert-braces
Position the cursor following the closing brace, if you are between braces	C-c } up-list
Check buffer for syntax errors	ESC x validate-tex-buffer
Process buffer in TeX or LaTeX	C-c C-b tex-buffer
Put the message shell on the screen, showing (at least) the last error message	C-c C-l tex-recenter-output- buffer
Process region in Text or LaTeX	C-c C-r tex-region
Kill TeXor LaTeX processing	C-c C-k tex-kill-job
Print TeX or LaTeX output	C-c C-p tex-print
Show print queue	C- c C-q tex-show-print-queue
Provide closing element of a command pair, in LaTeX mode only	C-c C-e tex-close-latex-block

Html-helper mode by Nelson Minar offers great flexibility in writing HTML, with hand-holding features that you can turn on or off, depending on your level of expertise and preferences. We prefer it to Emacs's own html mode.

Html-helper mode is not part of Emacs by default. It is available at ftp://ftp.reed.edu/pub/src/html-helper-mode.tar.gz.

Once you get this file, put it in a directory such as ~/elisp, move to that directory, and then type:

% gunzip html-helper-mode.tar.gz
% tar xvf html-helper-mode.tar

To make html-helper mode part of your startup, put the following lines in your .emacs file:

(setq load-path (cons "PUT_THE_PATH_HERE" 
load-path))
(autoload 'html-helper-mode "html-helper-mode"  
"Yay HTML" t)
(setq auto-mode-alist (cons '("\\.html$" .  
html-helper-mode)auto-mode-alist))

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Writing Macros

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To	Keystrokes Command Name
Start defining a macro	C-x ( start-kbd-macro
End macro definition	C-x ) end-kbd-macro
Execute last macro defined	C-x e call-last-kbd-macro
Execute the last macro defined n times	ESC n C-x e digit-argument; call-last- kbd-macro
Execute the last macro defined and then add keystrokes to it	C-u C-x ( universal-argument; start-kbd-macro
Name the last macro created (a preface to saving it)	ESC x name-last-kbd-macro
Save a named macro in a file	ESC x insert-keyboard-macro
Load a named macro	ESC x load-file
Execute a named macro	ESC macroname
Insert a query in a macro definition	C-x q kbd-macro-query
Insert a recursive edit in a macro definition	C-u C-x q universal argument; kbd-macro-query
Exit a recursive edit	ESC C-c exit-recursive-edit

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Customizing Emacs

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You customize key bindings using one of three functions: define-key, global-set-key, or local-set-key. Their forms are:

(define-key keymap "keystroke" 'command-name)
(global-set-key "keystroke" 'command-name)
(local-set-key "keystroke" 'command-name)

Notice the double quotes around keystroke and the single quote preceding command-name. This is LISP syntax. The "keystroke" is one or more characters, either printable or special characters. Special characters, such as ESC, should be represented as shown in the table below.

Section 1.11.1.1: Special character conventions

Special Character	Definition
\C-n	C-n (where n is any letter)
\C-[ or \e	ESC
\C-j or \n	LINEFEED
\C-m or \r	RETURN
\C-i or \T	TAB

To set the value of a variable, use the setq function in your .emacs file, as in:

(setq auto-save-interval 800)

Although auto-save-interval takes an integer value, many Emacs variables take "true" or "false" values. In Emacs LISP, t is true and nil is false. Emacs variables can also take other types of values; here is how to specify them:

• Strings of characters are surrounded by double quotes.

• Characters are specified like strings but with a ? preceding them, and they are not surrounded by double quotes. Thus, ?x and ?\C-c are character values x and C-c, respectively.

• Symbols are specified by a single quote followed by a symbol name—for example, 'never.

A list of some useful Emacs variables with descriptions and default values follows.

Section 1.11.2.1: Backups and auto-save

Variable Default	Description
make-backup-files t	If t, create a backup version of the current file before saving it for the first time.
backup-by-copying nil	If t, create backup files by copying rather than renaming the file. The default is renaming, which is more efficient.
version-control nil	If t, create numbered versions of files as backups (with names of the form file-name~n~). If nil, only do this for files that have numbered versions already. If 'never, never make numbered versions.
kept-new-versions 2	Number of latest versions of a file to keep when a new numbered backup is made.

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Emacs for Programmers

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Some of Emacs's commands are common to all supported programming languages.

To	Keystrokes Command Name
Indent each line between the cursor and mark	ESC C-\ indent-region
Move to the first nonblank character on the line	ESC m back-to-indentation
Join this line to the previous one	ESC ^ delete-indentation
Format and indent a comment	ESC ; indent-for-comment

To	Keystrokes Command Name
Move to the beginning of the current statement	ESC a c-beginning-of-statement
Move to the end of the current statement	ESC e c-end-of-statement
Fill the paragraph, preserving indentations and decorations, if in comment	ESC x c-fill-paragraph
Move to the beginning of current function	ESC C-a beginning-of-defun
Move to the end of current function	ESC C-e end-of-defun
Put the cursor at the beginning of function, mark at the end	C-c RETURN c-mark-function
Indent the entire function according to indentation style	C-c C-q c-indent-defun
Indent a balanced expression according to indentation style	ESC C-q c-indent-exp
Toggle auto state, in which Emacs automatically indents or inserts newlines when "electric" characters are typed ( { } : # ; , / *)	C-c C-a c-toggle-auto-state
Toggle hungry state, in which Emacs deletes groups of spaces with a single DEL	C-c C-d c-toggle-hungry-state
Toggle auto-hungry state, in which Emacs deletes groups of spaces and the newline that precedes them with a single DEL	C-c C-t c-toggle-auto-hungry- state
Move to the beginning of the current preprocessor conditional	C-c C-u c-up-conditional
Move to the previous preprocessor conditional	C-c C-p c-backward-conditional
Move to the next preprocessor conditional	C-c C-n c-forward-conditional
Add and align backslashes at the end of each line in the region	C-c C-\ c-backslash-region
Comment the current region	C-c C-c comment-region

Section 1.12.2.1: Customizing code indentation style

To select a code indentation style, type C-c . (for c-set-style). Possible styles are shown in the following table.

Style	Description
cc-mode	The default coding style, from which all others are derived

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Version ControlUnder Emacs

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To	Keystrokes Command Name
Go to the next logical version control state	C-x v v vc-next-action
Show all registered files beneath a directory	C-x v d vc-directory
Generate a version difference report	C-x v = vc-diff
Throw away changes since the last checked-in revision	C-x v u vc-revert-buffer