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GNU Emacs
Pocket Reference
Debra Cameron

Beijing • Cambridge • Farnham • Köln • Paris • Sebastopol • Taipei • Tokyo

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GNU Emacs Pocket Reference
by Debra Cameron
Copyright  1999 O'Reilly & Associates, Inc. All rights reserved.
Printed in the United States of America.
Editor: Gigi Estabrook
Production Editor: Claire Cloutier LeBlanc
Production Services: Omegatype Typography, Inc.
Cover Design: Edie Freedman


Printing History:
January 1999:

First Edition

Nutshell Handbook, the Nutshell Handbook logo, and the O'Reilly logo are registered
trademarks of O'Reilly & Associates, Inc. The association between the image of a gnu and the
topic of GNU Emacs is a trademark of O'Reilly & Associates, Inc.
Many of the designations used by manufacturers and sellers to distinguish their products are
claimed as trademarks. Where those designations appear in this book, and O'Reilly &
Associates, Inc. was aware of a trademark claim, the designations have been printed in caps or


5

3. Search and Replace Operations

10

4. Using Buffers and Windows

15

5. Emacs as a Work Environment

19

6. Email and Newsgroups

24

7. Emacs and the Internet

27


8. Simple Text Formatting and Specialized Editing

29

9. Marking Up Text with Emacs



Emacs Commands
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
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.)

1.
Emacs Basics
A Word About Modes

(table continued from previous page)
Major Mode

Function

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 writing LISP programs

LISP interaction mode

For writing and evaluating LISP expressions

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

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Start Emacs

emacs

Edit a specific file in Emacs

emacs filename

Exit Emacs

C-x C-c
save-buffers-kill-emacs

Suspend Emacs temporarily

C-z
suspend-emacs

Working with Files
To

Keystrokes Command Name

Open a file

C-x C-f
find-file

Open a different file instead


To

Keystrokes Command Name

Move to an existing buffer

C-x b buffername
switch-to-buffer

Display the buffer list

C-x C-b
list-buffers

Letting Emacs Fill in the Blanks
Emacs has a very helpful feature known as completion. If you open an existing file, type only
the first few letters of the name, enough to make a unique filename. Press TAB, and Emacs
completes the filename for you. Completion also works for long command names.

2.
Editing Files
Working in Text Mode
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)


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


universal-argument

Repeat the following command 16
times

C-u C-u
universal-argument


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To

Keystrokes Command Name

Repeat a complex command (can edit
arguments)

C-x ESC ESC
repeat-complex-command

Recall previous command in
minibuffer

ESC p
previous-history-element

Cutting Text


C-k
kill-line

Marking Text to Delete, Move, or Copy
In Emacs, you mark regions of text, which you can then delete, move, or copy. A region is the
area between the point (the cursor) and the mark (which you set).
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To

Keystrokes
Command Name

Set the mark (beginning or end of a
region)

C-@ or C-SPACE
set-mark-command

Delete marked text

C-w
kill-region

Copy a region

ESC w or C-Insert
kill-ring-save


Copy region to the kill ring

Right mouse button
x-cut-text

Cut region

C-middle button
x-cut-and-wipe-text

Split window vertically

C-right button
x-mouse-select-and-split

Copy region to the kill ring

S-middle button
x-cut-text

Paste text

S-right
x-paste-text

Delete all other windows but this one

C-S-right button
x-mouse-keep-one-window


ESC u
upcase-word

Lowercase word

ESC l
downcase-word

Stopping Commands
When you want to stop any command that's in progress, press C-g. The word Quit appears in
the command area.

Undoing Edits
What happens if you make a mistake while you're editing? You can undo your changes by
pressing C-x u.
What if you'd like to redo a command after you type undo? There is no formal redo command,
but you can use undo in the following way. Move the cursor in any direction, and type C-x u
again. Emacs redoes the last command. You can repeat it to redo previous undos.
Although undo is an important command, it can be slow if you want to undo a large number of
changes. The following table summarizes three methods for undoing changes and the
circumstances for their use.
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If you

Use this command

Don't like the recent changes you've
made and want to undo them one by one


3.
Search and Replace Operations
Incremental Search
An incremental search begins when you type the first letter and
continues searching as you add characters.
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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

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)

,

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To


ESC C-c

Exit recursive edit and exit query-replace

C-]

Regular Expression Search and Replace
This section lists characters for creating regular expressions, followed by commands for
replacement operations using regular expressions.

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)

\

Search incrementally forward for a
regular expression

ESC C-s
isearch-forward-regexp

Repeat incremental regular
expression search

C-s
isearch-forward


expression search

isearch-forward

Search incrementally backward for a
regular expression

ESC C-r
isearch-backward-regexp

Query-replace a regular expression

ESC x query-replace-regexp

Globally replace a regular expression
unconditionally (use with caution)


ESC x ispell-continue

Kill the spellcheck process

ESC x ispell-kill-ispell

List possible completions for current
word (text mode)

ESC TAB
ispell-complete-word

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Word Abbreviations
Abbreviations can be used as shortcuts for long words or defined as the correct spelling for
commonly misspelled words.
Global abbreviations work in every major mode; local abbreviations work only in the mode in
which they were defined. To define abbreviations, you must first enter word abbreviation
mode.
To

Keystrokes Command Name

Enter (or exit) word abbreviation
mode

ESC x abbrev-mode

Define a global abbreviation

ESC x kill-all-abbrevs

To add word abbreviations to your startup, insert these lines in your .emacs file:
(setq-default abbrev-mode t)
(read-abbrev-file “~/.abbrev_defs”)
(setq save-abbrevs t)

After making these modifications, restart Emacs and define an abbreviation. Ignore the error
message that appears. During this first session, you will need to issue the following
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command: ESC x write-abbrev-file RETURN~/.abbrev_defs RETURN. After this initial
session, this file will be loaded and saved automatically.

4.
Using Buffers and Windows
Using Buffers
To

Keystrokes
Command Name

Move to the buffer specified

C-x b buffername
switch-to-buffer

Display the buffer list

C-x C-b


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



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

Using Windows


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

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

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Using Frames
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


C-x r m
bookmark-set

Jump to a bookmark

C-x r b
bookmark-jump

Rename a bookmark

ESC x bookmark-rename

Delete a bookmark

ESC x bookmark-delete

Save bookmarks

ESC x bookmark-save

Move to bookmark list

C-x r l
bookmark-bmenu-list

(table continued on next page)
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(table continued from previous page)


d

Rename bookmark

r

Save all bookmarks listed

s

Display the bookmark the cursor is on

f

Mark bookmarks to be displayed in multiple windows

m

Display marked bookmarks or the one the cursor is on if none
is marked

v

Toggle display of paths to files associated with bookmarks

t

Display location of file associated with bookmark


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


comint-send-eof
Erase current line; C-u in UNIX
shells

C-c C-u
comint-kill-input

(table continued on next page)
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To

Keystrokes
Command Name

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

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

To

Keystrokes
Command Name


revert-buffer

Change group permissions

G
dired-do-chgrp

Remove line from display (don't
delete it)

k

Mark with ∗

m

dired-do-kill-lines

dired-mark
Move to the next line

n
dired-next-line

Find file in another window; move
there

o
dired-find-file-other-window



Rename file

R
dired-do-rename

Unmark file

u
dired-unmark

View file

v
dired-view-file


dired-view-file
Delete files flagged with D

x
dired-do-flagged-delete

Compress file

Z
dired-do-compress

Unmark all files (no matter what the
mark was)


=

Compare this file with its backup file

ESC =
dired-backup-diff

Execute shell command on this file

!

dired-mark-directories

dired-diff

dired-do-shell-command
Move to the next file marked with ∗
or D

ESC }
dired-next-marked-file

(table continued on next page)
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(table continued from previous page)

To


>
dired-next-dirline

Move to previous directory



calendar-print-day-of-year

Scroll the other window

SPACE
scroll-other-window

Quit calendar

q
exit-calendar

Add a weekly entry based on the day
of the week

iw
insert-weekly-diary-entry


of the week
Add an annual entry

insert-weekly-diary-entry
iy
insert-yearly-diary-entry

Add an entry for a particular day

id
insert-diary-entry

horizontally

C-SPACE or C-@
calendar-set-mark

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6.
Email and Newsgroups
Sending Mail
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