path: root/info/emacs-6

This is Info file ../info/emacs, produced by Makeinfo-1.49 from the
input file emacs.texi.

   This file documents the GNU Emacs editor.

   Copyright (C) 1985, 1986, 1988, 1992 Richard M. Stallman.

   Permission is granted to make and distribute verbatim copies of this
manual provided the copyright notice and this permission notice are
preserved on all copies.

   Permission is granted to copy and distribute modified versions of
this manual under the conditions for verbatim copying, provided also
that the sections entitled "The GNU Manifesto", "Distribution" and "GNU
General Public License" are included exactly as in the original, and
provided that the entire resulting derived work is distributed under the
terms of a permission notice identical to this one.

   Permission is granted to copy and distribute translations of this
manual into another language, under the above conditions for modified
versions, except that the sections entitled "The GNU Manifesto",
"Distribution" and "GNU General Public License" may be included in a
translation approved by the author instead of in the original English.


File: emacs,  Node: Several Buffers,  Prev: Kill Buffer,  Up: Buffers

Operating on Several Buffers
============================

   The "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 "deleting" them, for consistency with Dired), or display
them.

`M-x buffer-menu'
     Begin editing a buffer listing all Emacs buffers.

   The command `buffer-menu' writes a list of all Emacs buffers into
the buffer `*Buffer List*', and selects that buffer in Buffer Menu
mode.  The buffer is read-only, and can only be changed through the
special commands described in this section.  Most of these commands are
graphic characters.  The usual Emacs cursor motion commands can be used
in the `*Buffer List*' buffer.  The following special commands apply to
the buffer described on the current line.

`d'
     Request to delete (kill) the buffer, then move down.  The request
     shows as a `D' on the line, before the buffer name.  Requested
     deletions take place when the `x' command is used.

`k'
     Synonym for `d'.

`C-d'
     Like `d' but move up afterwards instead of down.

`s'
     Request to save the buffer.  The request shows as an `S' on the
     line.  Requested saves take place when the `x' command is used.
     You may request both saving and deletion for the same buffer.

`~'
     Mark buffer "unmodified".  The command `~' does this immediately
     when typed.

`x'
     Perform previously requested deletions and saves.

`u'
     Remove any request made for the current line, and move down.

`DEL'
     Move to previous line and remove any request made for that line.

   All the commands that put in or remove flags to request later
operations also move down a line, and accept a numeric argument as a
repeat count, unless otherwise specified.

   There are also special commands to use the buffer list to select
another buffer, and to specify one or more other buffers for display in
additional windows.

`1'
     Select the buffer in a full-screen window.  This command takes
     effect immediately.

`2'
     Immediately set up two windows, with this buffer in one, and the
     previously selected buffer (aside from the buffer `*Buffer List*')
     in the other.

`f'
     Immediately select the buffer in place of the `*Buffer List*'
     buffer.

`o'
     Immediately select the buffer in another window as if by `C-x 4 b',
     leaving `*Buffer List*' visible.

`q'
     Immediately select this buffer, and also display in other windows
     any buffers previously flagged with the `m' command.  If there are
     no such buffers, this command is equivalent to `1'.

`m'
     Flag this buffer to be displayed in another window if the `q'
     command is used.  The request shows as a `>' at the beginning of
     the line.  The same buffer may not have both a delete request and a
     display request.

   All that `buffer-menu' does directly is create and select a suitable
buffer, and turn on Buffer Menu mode.  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 `*Buffer List*'
buffer to another Emacs buffer, and edit there.  You can reselect the
`buffer-menu' buffer later, to perform the operations already
requested, or you can kill it, or pay no further attention to it.

   The only difference between `buffer-menu' and `list-buffers' is that
`buffer-menu' selects the `*Buffer List*' buffer and `list-buffers'
does not.  If you run `list-buffers' (that is, type `C-x C-b') and
select the buffer list manually, you can use all of the commands
described here.


File: emacs,  Node: Windows,  Next: Major Modes,  Prev: Buffers,  Up: Top

Multiple Windows
****************

   Emacs can split the screen into two or many windows, which can
display parts of different buffers, or different parts of one buffer.

* Menu:

* Basic Window::     Introduction to Emacs windows.
* Split Window::     New windows are made by splitting existing windows.
* Other Window::     Moving to another window or doing something to it.
* Pop Up Window::    Finding a file or buffer in another window.
* Change Window::    Deleting windows and changing their sizes.


File: emacs,  Node: Basic Window,  Next: Split Window,  Prev: Windows,  Up: Windows

Concepts of Emacs Windows
=========================

   When multiple windows are being displayed, each window has an Emacs
buffer designated for display in it.  The same buffer may appear in more
than one window; if it does, any changes in its text are displayed in
all the windows where it appears.  But the windows showing the same
buffer can show different parts of it, because each window has its own
value of point.

   At any time, one of the windows is the "selected window"; the buffer
this window is displaying is the current buffer.  The terminal's cursor
shows the location of point in this window.  Each other window has a
location of point as well, but since the terminal has only one cursor
there is no way to show where those locations are.

   Commands to move point affect the value of point for the selected
Emacs window only.  They do not change the value of point in any other
Emacs window, even one showing the same buffer.  The same is true for
commands such as `C-x b' to change the selected buffer in the selected
window; they do not affect other windows at all.  However, there are
other commands such as `C-x 4 b' that select a different window and
switch buffers in it.  Also, all commands that display information in a
window, including (for example) `C-h f' (`describe-function') and `C-x
C-b' (`list-buffers'), work by switching buffers in a nonselected window
without affecting the selected window.

   Each window has its own mode line, which displays the buffer name,
modification status and major and minor modes of the buffer that is
displayed in the window.  *Note Mode Line::, for full details on the
mode line.


File: emacs,  Node: Split Window,  Next: Other Window,  Prev: Basic Window,  Up: Windows

Splitting Windows
=================

`C-x 2'
     Split the selected window into two windows, one above the other
     (`split-window-vertically').

`C-x 5'
     Split the selected window into two windows positioned side by side
     (`split-window-horizontally').

   The command `C-x 2' (`split-window-vertically') breaks the selected
window into two windows, one above the other.  Both windows start out
displaying the same buffer, with the same value of point.  By default
the two windows each get half the height of the window that was split; a
numeric argument specifies how many lines to give to the top window.

   `C-x 5' (`split-window-horizontally') breaks the selected window
into two side-by-side windows.  A numeric argument specifies how many
columns to give the one on the left.  A line of vertical bars separates
the two windows.  Windows that are not the full width of the screen
have mode lines, but they are truncated; also, they do not always
appear in inverse video, because, the Emacs display routines have not
been taught how to display a region of inverse video that is only part
of a line on the screen.

   When a window is less than the full width, text lines too long to
fit are frequent.  Continuing all those lines might be confusing.  The
variable `truncate-partial-width-windows' can be set non-`nil' to force
truncation in all windows less than the full width of the screen,
independent of the buffer being displayed and its value for
`truncate-lines'.  *Note Continuation Lines::.

   Horizontal scrolling is often used in side-by-side windows. *Note
Display::.


File: emacs,  Node: Other Window,  Next: Pop Up Window,  Prev: Split Window,  Up: Windows

Using Other Windows
===================

`C-x o'
     Select another window (`other-window').  That is `o', not zero.

`C-M-v'
     Scroll the next window (`scroll-other-window').

`M-x compare-windows'
     Find next place where the text in the selected window does not
     match the text in the next window.

   To select a different window, use `C-x o' (`other-window'). That is
an `o', for `other', not a zero.  When there are more than two windows,
this command moves through all the windows in a cyclic order, generally
top to bottom and left to right.  From the rightmost and bottommost
window, it goes back to the one at the upper left corner.  A numeric
argument means to move several steps in the cyclic order of windows.  A
negative argument moves around the cycle in the opposite order. When
the minibuffer is active, the minibuffer is the last window in the
cycle; you can switch from the minibuffer window to one of the other
windows, and later switch back and finish supplying the minibuffer
argument that is requested.  *Note Minibuffer Edit::.

   The usual scrolling commands (*note Display::.) apply to the selected
window only, but there is one command to scroll the next window.
`C-M-v' (`scroll-other-window') scrolls the window that `C-x o' would
select.  It takes arguments, positive and negative, like `C-v'.

   The command `M-x compare-windows' compares the text in the current
window with that in the next window.  Comparison starts at point in each
window.  Point moves forward in each window, a character at a time in
each window, until the next characters in the two windows are
different.  Then the command is finished.


File: emacs,  Node: Pop Up Window,  Next: Change Window,  Prev: Other Window,  Up: Windows

Displaying in Another Window
============================

   `C-x 4' is a prefix key for commands that select another window
(splitting the window if there is only one) and select a buffer in that
window.  Different `C-x 4' commands have different ways of finding the
buffer to select.

`C-x 4 b BUFNAME RET'
     Select buffer BUFNAME in another window.  This runs
     `switch-to-buffer-other-window'.

`C-x 4 f FILENAME RET'
     Visit file FILENAME and select its buffer in another window.  This
     runs `find-file-other-window'.  *Note Visiting::.

`C-x 4 d DIRECTORY RET'
     Select a Dired buffer for directory DIRECTORY in another window.
     This runs `dired-other-window'.  *Note Dired::.

`C-x 4 m'
     Start composing a mail message in another window.  This runs
     `mail-other-window', and its same-window version is `C-x m' (*note
     Sending Mail::.).

`C-x 4 .'
     Find a tag in the current tag table in another window.  This runs
     `find-tag-other-window', the multiple-window variant of `M-.'
     (*note Tags::.).


File: emacs,  Node: Change Window,  Prev: Pop Up Window,  Up: Windows

Deleting and Rearranging Windows
================================

`C-x 0'
     Get rid of the selected window (`kill-window').  That is a zero.

`C-x 1'
     Get rid of all windows except the selected one
     (`delete-other-windows').

`C-x ^'
     Make the selected window taller, at the expense of the other(s)
     (`enlarge-window').

`C-x }'
     Widen the selected window (`enlarge-window-horizontally').

   To delete a window, type `C-x 0' (`delete-window').  (That is a
zero.)  The space occupied by the deleted window is distributed among
the other active windows (but not the minibuffer window, even if that
is active at the time).  Once a window is deleted, its attributes are
forgotten; there is no automatic way to make another window of the same
shape or showing the same buffer.  But the buffer continues to exist,
and you can select it in any window with `C-x b'.

   `C-x 1' (`delete-other-windows') is more powerful than `C-x 0'; it
deletes all the windows except the selected one (and the minibuffer);
the selected window expands to use the whole screen except for the echo
area.

   To readjust the division of space among existing windows, use `C-x ^'
(`enlarge-window').  It makes the currently selected window get one
line bigger, or as many lines as is specified with a numeric argument.
With a negative argument, it makes the selected window smaller.  `C-x
}' (`enlarge-window-horizontally') makes the selected window wider by
the specified number of columns.  The extra screen space given to a
window comes from one of its neighbors, if that is possible; otherwise,
all the competing windows are shrunk in the same proportion.  If this
makes any windows too small, those windows are deleted and their space
is divided up. The minimum size is specified by the variables
`window-min-height' and `window-min-width'.


File: emacs,  Node: Major Modes,  Next: Indentation,  Prev: Windows,  Up: Top

Major Modes
***********

   Emacs has many different "major modes", each of which customizes
Emacs for editing text of a particular sort.  The major modes are
mutually exclusive, and each buffer has one major mode at any time. 
The mode line normally contains the name of the current major mode, in
parentheses. *Note Mode Line::.

   The least specialized major mode is called "Fundamental mode".  This
mode has no mode-specific redefinitions or variable settings, so that
each Emacs command behaves in its most general manner, and each option
is in its default state.  For editing any specific type of text, such
as Lisp code or English text, you should switch to the appropriate
major mode, such as Lisp mode or Text mode.

   Selecting a major mode changes the meanings of a few keys to become
more specifically adapted to the language being edited.  The ones which
are changed frequently are TAB, DEL, and LFD.  In addition, the
commands which handle comments use the mode to determine how comments
are to be delimited.  Many major modes redefine the syntactical
properties of characters appearing in the buffer.  *Note Syntax::.

   The major modes fall into three major groups.  Lisp mode (which has
several variants), C mode and Muddle mode are for specific programming
languages.  Text mode, Nroff mode, TeX mode and Outline mode are for
editing English text.  The remaining major modes are not intended for
use on users' files; they are used in buffers created for specific
purposes by Emacs, such as Dired mode for buffers made by Dired (*note
Dired::.), and Mail mode for buffers made by `C-x m' (*note Sending
Mail::.), and Shell mode for buffers used for communicating with an
inferior shell process (*note Interactive Shell::.).

   Most programming language major modes specify that only blank lines
separate paragraphs.  This is so that the paragraph commands remain
useful. *Note Paragraphs::.  They also cause Auto Fill mode to use the
definition of TAB to indent the new lines it creates.  This is because
most lines in a program are usually indented.  *Note Indentation::.

* Menu:

* Choosing Modes::     How major modes are specified or chosen.


File: emacs,  Node: Choosing Modes,  Prev: Major Modes,  Up: Major Modes

How Major Modes are Chosen
==========================

   You can select a major mode explicitly for the current buffer, but
most of the time Emacs determines which mode to use based on the file
name or some text in the file.

   Explicit selection of a new major mode is done with a `M-x' command.
From the name of a major mode, add `-mode' to get the name of a command
to select that mode.  Thus, you can enter Lisp mode by executing `M-x
lisp-mode'.

   When you visit a file, Emacs usually chooses the right major mode
based on the file's name.  For example, files whose names end in `.c'
are edited in C mode.  The correspondence between file names and major
mode is controlled by the variable `auto-mode-alist'.  Its value is a
list in which each element has the form

     (REGEXP . MODE-FUNCTION)

For example, one element normally found in the list has the form
`("\\.c$" . c-mode)', and it is responsible for selecting C mode for
files whose names end in `.c'.  (Note that `\\' is needed in Lisp
syntax to include a `\' in the string, which is needed to suppress the
special meaning of `.' in regexps.)  The only practical way to change
this variable is with Lisp code.

   You can specify which major mode should be used for editing a certain
file by a special sort of text in the first nonblank line of the file. 
The mode name should appear in this line both preceded and followed by
`-*-'.  Other text may appear on the line as well.  For example,

     ;-*-Lisp-*-

tells Emacs to use Lisp mode.  Note how the semicolon is used to make
Lisp treat this line as a comment.  Such an explicit specification
overrides any defaulting based on the file name.

   Another format of mode specification is

     -*-Mode: MODENAME;-*-

which allows other things besides the major mode name to be specified.
However, Emacs does not look for anything except the mode name.

   The major mode can also be specified in a local variables list.
*Note File Variables::.

   When a file is visited that does not specify a major mode to use, or
when a new buffer is created with `C-x b', the major mode used is that
specified by the variable `default-major-mode'.  Normally this value is
the symbol `fundamental-mode', which specifies Fundamental mode. If
`default-major-mode' is `nil', the major mode is taken from the
previously selected buffer.

   The command `M-x normal-mode' recalculates the major mode from the
visited file name and the contents of the buffer.


File: emacs,  Node: Indentation,  Next: Text,  Prev: Major Modes,  Up: Top

Indentation
***********

`TAB'
     Indent current line "appropriately" in a mode-dependent fashion.

`LFD'
     Perform RET followed by TAB (`newline-and-indent').

`M-^'
     Merge two lines (`delete-indentation').  This would cancel out the
     effect of LFD.

`C-M-o'
     Split line at point; text on the line after point becomes a new
     line indented to the same column that it now starts in
     (`split-line').

`M-m'
     Move (forward or back) to the first nonblank character on the
     current line (`back-to-indentation').

`C-M-\'
     Indent several lines to same column (`indent-region').

`C-x TAB'
     Shift block of lines rigidly right or left (`indent-rigidly').

`M-i'
     Indent from point to the next prespecified tab stop column
     (`tab-to-tab-stop').

`M-x indent-relative'
     Indent from point to under an indentation point in the previous
     line.

   Most programming languages have some indentation convention.  For
Lisp code, lines are indented according to their nesting in
parentheses.  The same general idea is used for C code, though many
details are different.

   Whatever the language, to indent a line, use the TAB command.  Each
major mode defines this command to perform the sort of indentation
appropriate for the particular language.  In Lisp mode, TAB aligns the
line according to its depth in parentheses.  No matter where in the
line you are when you type TAB, it aligns the line as a whole.  In C
mode, TAB implements a subtle and sophisticated indentation style that
knows about many aspects of C syntax.

   In Text mode, TAB runs the command `tab-to-tab-stop', which indents
to the next tab stop column.  You can set the tab stops with `M-x
edit-tab-stops'.

* Menu:

* Indentation Commands:: Various commands and techniques for indentation.
* Tab Stops::            You can set arbitrary "tab stops" and then
                         indent to the next tab stop when you want to.
* Just Spaces::          You can request indentation using just spaces.


File: emacs,  Node: Indentation Commands,  Next: Tab Stops,  Prev: Indentation,  Up: Indentation

Indentation Commands and Techniques
===================================

   If you just want to insert a tab character in the buffer, you can
type `C-q TAB'.

   To move over the indentation on a line, type `Meta-m'. This command,
given anywhere on a line, positions point at the first nonblank
character on the line (`back-to-indentation').

   To insert an indented line before the current line, do `C-a C-o
TAB'.  To make an indented line after the current line, use `C-e LFD'.

   `C-M-o' (`split-line') moves the text from point to the end of the
line vertically down, so that the current line becomes two lines.
`C-M-o' first moves point forward over any spaces and tabs.  Then it
inserts after point a newline and enough indentation to reach the same
column point is on.  Point remains before the inserted newline; in this
regard, `C-M-o' resembles `C-o'.

   To join two lines cleanly, use the `Meta-^' (`delete-indentation')
command to delete the indentation at the front of the current line, and
the line boundary as well.  They are replaced by a single space, or by
no space if point after joining is at the beginning of a line or before
a `)' or after a `('.  To delete just the indentation of a line, go to
the beginning of the line and use `Meta-\' (`delete-horizontal-space'),
which deletes all spaces and tabs around the cursor.

   There are also commands for changing the indentation of several
lines at once.  `Control-Meta-\' (`indent-region') gives each line which
begins in the region the "usual" indentation by invoking TAB at the
beginning of the line.  A numeric argument specifies the column to
indent to, and each line is shifted left or right so that its first
nonblank character appears in that column.  `C-x TAB'
(`indent-rigidly') moves all of the lines in the region right by its
argument (left, for negative arguments).  The whole group of lines moves
rigidly sideways, which is how the command gets its name.

   `M-x indent-relative' indents at point based on the previous line
(actually, the last nonempty line.)  It inserts whitespace at point,
moving point, until it is underneath an indentation point in the
previous line. An indentation point is the end of a sequence of
whitespace or the end of the line.  If point is farther right than any
indentation point in the previous line, the whitespace before point is
deleted and the first indentation point then applicable is used.  If no
indentation point is applicable even then, `tab-to-tab-stop' is run
(see next section).

   `indent-relative' is the definition of TAB in Indented Text mode. 
*Note Text::.


File: emacs,  Node: Tab Stops,  Next: Just Spaces,  Prev: Indentation Commands,  Up: Indentation

Tab Stops
=========

   For typing in tables, you can use Text mode's definition of TAB,
`tab-to-tab-stop'.  This command inserts indentation before point,
enough to reach the next tab stop column.  If you are not in Text mode,
this function can be found on `M-i' anyway.

   The tab stops used by `M-i' can be set arbitrarily by the user. They
are stored in a variable called `tab-stop-list', as a list of
column-numbers in increasing order.

   The convenient way to set the tab stops is using `M-x
edit-tab-stops', which creates and selects a buffer containing a
description of the tab stop settings.  You can edit this buffer to
specify different tab stops, and then type `C-c C-c' to make those new
tab stops take effect.  In the tab stop buffer, `C-c C-c' runs the
function `edit-tab-stops-note-changes' rather than its usual definition
`save-buffer'.  `edit-tab-stops' records which buffer was current when
you invoked it, and stores the tab stops back in that buffer; normally
all buffers share the same tab stops and changing them in one buffer
affects all, but if you happen to make `tab-stop-list' local in one
buffer then `edit-tab-stops' in that buffer will edit the local
settings.

   Here is what the text representing the tab stops looks like for
ordinary tab stops every eight columns.

             :       :       :       :       :       :
     0         1         2         3         4
     0123456789012345678901234567890123456789012345678
     To install changes, type C-c C-c

   The first line contains a colon at each tab stop.  The remaining
lines are present just to help you see where the colons are and know
what to do.

   Note that the tab stops that control `tab-to-tab-stop' have nothing
to do with displaying tab characters in the buffer.  *Note Display
Vars::, for more information on that.


File: emacs,  Node: Just Spaces,  Prev: Tab Stops,  Up: Indentation

Tabs vs. Spaces
===============

   Emacs normally uses both tabs and spaces to indent lines.  If you
prefer, all indentation can be made from spaces only.  To request this,
set `indent-tabs-mode' to `nil'.  This is a per-buffer variable;
altering the variable affects only the current buffer, but there is a
default value which you can change as well.  *Note Locals::.

   There are also commands to convert tabs to spaces or vice versa,
always preserving the columns of all nonblank text.  `M-x tabify' scans
the region for sequences of spaces, and converts sequences of at least
three spaces to tabs if that can be done without changing indentation. 
`M-x untabify' changes all tabs in the region to appropriate numbers of
spaces.


File: emacs,  Node: Text,  Next: Programs,  Prev: Indentation,  Up: Top

Commands for Human Languages
****************************

   The term "text" has two widespread meanings in our area of the
computer field.  One is data that is a sequence of characters.  Any file
that you edit with Emacs is text, in this sense of the word.  The other
meaning is more restrictive: a sequence of characters in a human
language for humans to read (possibly after processing by a text
formatter), as opposed to a program or commands for a program.

   Human languages have syntactic/stylistic conventions that can be
supported or used to advantage by editor commands: conventions involving
words, sentences, paragraphs, and capital letters.  This chapter
describes Emacs commands for all of these things.  There are also
commands for "filling", or rearranging paragraphs into lines of
approximately equal length.  The commands for moving over and killing
words, sentences and paragraphs, while intended primarily for editing
text, are also often useful for editing programs.

   Emacs has several major modes for editing human language text. If
the file contains text pure and simple, use Text mode, which customizes
Emacs in small ways for the syntactic conventions of text.  For text
which contains embedded commands for text formatters, Emacs has other
major modes, each for a particular text formatter.  Thus, for input to
TeX, you would use TeX mode; for input to nroff, Nroff mode.

* Menu:

* Text Mode::   The major modes for editing text files.
* Nroff Mode::  The major mode for editing input to the formatter nroff.
* TeX Mode::    The major modes for editing input to the formatter TeX.
* Outline Mode::The major mode for editing outlines.
* Words::       Moving over and killing words.
* Sentences::   Moving over and killing sentences.
* Paragraphs::	Moving over paragraphs.
* Pages::	Moving over pages.
* Filling::     Filling or justifying text
* Case::        Changing the case of text


File: emacs,  Node: Text Mode,  Next: Words,  Prev: Text,  Up: Text

Text Mode
=========

   Editing files of text in a human language ought to be done using Text
mode rather than Lisp or Fundamental mode.  Invoke `M-x text-mode' to
enter Text mode.  In Text mode, TAB runs the function
`tab-to-tab-stop', which allows you to use arbitrary tab stops set with
`M-x edit-tab-stops' (*note Tab Stops::.).  Features concerned with
comments in programs are turned off except when explicitly invoked.  The
syntax table is changed so that periods are not considered part of a
word, while apostrophes, backspaces and underlines are.

   A similar variant mode is Indented Text mode, intended for editing
text in which most lines are indented.  This mode defines TAB to run
`indent-relative' (*note Indentation::.), and makes Auto Fill indent
the lines it creates.  The result is that normally a line made by Auto
Filling, or by LFD, is indented just like the previous line.  Use `M-x
indented-text-mode' to select this mode.

   Entering Text mode or Indented Text mode calls with no arguments the
value of the variable `text-mode-hook', if that value exists and is not
`nil'.  This value is also called when modes related to Text mode are
entered; this includes Nroff mode, TeX mode, Outline mode and Mail
mode.  Your hook can look at the value of `major-mode' to see which of
these modes is actually being entered.

* Menu:

  Three modes similar to Text mode are of use for editing text that is to
be passed through a text formatter before achieving the form in which
humans are to read it.

* Nroff Mode::  The nroff formatter typesets text.
* TeX Mode::    The TeX formatter typesets text and mathematics.
* Texinfo Mode::Texinfo provides both on-line information and printed output
                 from the same source file.

  Another similar mode is used for editing outlines.  It allows you
to view the text at various levels of detail.  You can view either
the outline headings alone or both headings and text; you can also
hide some of the headings at lower levels from view to make the high
level structure more visible.

* Outline Mode::The major mode for editing outlines.


File: emacs,  Node: Nroff Mode,  Next: TeX Mode,  Prev: Text Mode,  Up: Text Mode

Nroff Mode
----------

   Nroff mode is a mode like Text mode but modified to handle nroff
commands present in the text.  Invoke `M-x nroff-mode' to enter this
mode.  It differs from Text mode in only a few ways.  All nroff command
lines are considered paragraph separators, so that filling will never
garble the nroff commands.  Pages are separated by `.bp' commands. 
Comments start with backslash-doublequote.  Also, three special
commands are provided that are not in Text mode:

`M-n'
     Move to the beginning of the next line that isn't an nroff command
     (`forward-text-line').  An argument is a repeat count.

`M-p'
     Like `M-n' but move up (`backward-text-line').

`M-?'
     Prints in the echo area the number of text lines (lines that are
     not nroff commands) in the region (`count-text-lines').

   The other feature of Nroff mode is Electric Nroff newline mode.  This
is a minor mode that you can turn on or off with `M-x
electric-nroff-mode' (*note Minor Modes::.).  When the mode is on, each
time you use RET to end a line that contains an nroff command that
opens a kind of grouping, it also inserts the matching nroff command to
close that grouping, on the following line.  For example, if you are at
the beginning of a line and type `. ( b RET', this inserts the matching
command `.)b' on a new line following point.

   Entering Nroff mode calls with no arguments the value of the variable
`text-mode-hook', if that value exists and is not `nil'; then it does
the same with the variable `nroff-mode-hook'.


File: emacs,  Node: TeX Mode,  Next: Texinfo Mode,  Prev: Nroff Mode,  Up: Text Mode

TeX Mode
--------

   TeX is a powerful text formatter written by Donald Knuth; it is also
free, like GNU Emacs.  LaTeX is a simplified input format for TeX,
implemented by TeX macros.  It comes with TeX.

   Emacs has a special TeX mode for editing TeX input files. It
provides facilities for checking the balance of delimiters and for
invoking TeX on all or part of the file.

   TeX mode has two variants, Plain TeX mode and LaTeX mode (actually
two distinct major modes which differ only slightly).  They are
designed for editing the two different input formats.  The command `M-x
tex-mode' looks at the contents of the buffer to determine whether the
contents appear to be LaTeX input or not; it then selects the
appropriate mode.  If it can't tell which is right (e.g., the buffer is
empty), the variable `TeX-default-mode' controls which mode is used.

   The commands `M-x plain-tex-mode' and `M-x latex-mode' explicitly
select the two variants of TeX mode.  Use these commands when `M-x
tex-mode' does not guess right.

* Menu:

* Editing: TeX Editing.   Special commands for editing in TeX mode.
* Printing: TeX Print.    Commands for printing part of a file with TeX.

   TeX for Unix systems can be obtained from the University of
Washington for a distribution fee.

   To order a full distribution, send $200.00 for a 1/2-inch 9-track
1600 bpi (`tar' or `cpio') tape reel, or $210.00 for a 1/4-inch 4-track
QIC-24 (`tar' or `cpio') cartridge, to:

     Northwest Computing Support Center
     DR-10, Thomson Hall 35
     University of Washington
     Seattle, Washington 98195

Please make checks payable to the University of Washington.

   Prepaid orders are preferred but purchase orders are acceptable;
however, purchase orders carry an extra charge of $10.00, to pay for
processing.

   Overseas sites: please add to the base cost $20.00 for shipment via
air parcel post, or $30.00 for shipment via courier.

   Please check with the Northwest Computing Support Center at the
University of Washington for current prices and formats:

     telephone:  (206) 543-6259
     email:      elisabet@u.washington.edu


File: emacs,  Node: TeX Editing,  Next: TeX Print,  Prev: TeX Mode,  Up: TeX Mode

TeX Editing Commands
....................

   Here are the special commands provided in TeX mode for editing the
text of the file.

`"'
     Insert, according to context, either ```' or `"' or `'''
     (`TeX-insert-quote').

`LFD'
     Insert a paragraph break (two newlines) and check the previous
     paragraph for unbalanced braces or dollar signs
     (`TeX-terminate-paragraph').

`M-x validate-TeX-buffer'
     Check each paragraph in the buffer for unbalanced braces or dollar
     signs.

`M-{'
     Insert `{}' and position point between them (`TeX-insert-braces').

`M-}'
     Move forward past the next unmatched close brace (`up-list').

`C-c C-f'
     Close a block for LaTeX (`TeX-close-LaTeX-block').

   In TeX, the character `"' is not normally used; use ```' to start a
quotation and `''' to end one.  TeX mode defines the key `"' to insert
```' after whitespace or an open brace, `"' after a backslash, or `'''
otherwise.  This is done by the command `TeX-insert-quote'.  If you
need the character `"' itself in unusual contexts, use `C-q' to insert
it.  Also, `"' with a numeric argument always inserts that number of
`"' characters.

   In TeX mode, `$' has a special syntax code which attempts to
understand the way TeX math mode delimiters match.  When you insert a
`$' that is meant to exit math mode, the position of the matching `$'
that entered math mode is displayed for a second.  This is the same
feature that displays the open brace that matches a close brace that is
inserted.  However, there is no way to tell whether a `$' enters math
mode or leaves it; so when you insert a `$' that enters math mode, the
previous `$' position is shown as if it were a match, even though they
are actually unrelated.

   If you prefer to keep braces balanced at all times, you can use `M-{'
(`TeX-insert-braces') to insert a pair of braces.  It leaves point
between the two braces so you can insert the text that belongs inside.
Afterward, use the command `M-}' (`up-list') to move forward past the
close brace.

   There are two commands for checking the matching of braces.  LFD
(`TeX-terminate-paragraph') checks the paragraph before point, and
inserts two newlines to start a new paragraph.  It prints a message in
the echo area if any mismatch is found.  `M-x validate-TeX-buffer'
checks the entire buffer, paragraph by paragraph.  When it finds a
paragraph that contains a mismatch, it displays point at the beginning
of the paragraph for a few seconds and pushes a mark at that spot. 
Scanning continues until the whole buffer has been checked or until you
type another key. The positions of the last several paragraphs with
mismatches can be found in the mark ring (*note Mark Ring::.).

   Note that square brackets and parentheses are matched in TeX mode,
not just braces.  This is wrong for the purpose of checking TeX syntax.
However, parentheses and square brackets are likely to be used in text
as matching delimiters and it is useful for the various motion commands
and automatic match display to work with them.

   In LaTeX input, `\begin' and `\end' commands must balance. After you
insert a `\begin', use `C-c C-f' (`TeX-close-LaTeX-block') to insert
automatically a matching `\end' (on a new line following the `\begin').
 A blank line is inserted between the two, and point is left there.


File: emacs,  Node: TeX Print,  Prev: TeX Editing,  Up: TeX Mode

TeX Printing Commands
.....................

   You can invoke TeX as an inferior of Emacs on either the entire
contents of the buffer or just a region at a time.  Running TeX in this
way on just one chapter is a good way to see what your changes look
like without taking the time to format the entire file.

`C-c C-r'
     Invoke TeX on the current region, plus the buffer's header
     (`TeX-region').

`C-c C-b'
     Invoke TeX on the entire current buffer (`TeX-buffer').

`C-c C-l'
     Recenter the window showing output from the inferior TeX so that
     the last line can be seen (`TeX-recenter-output-buffer').

`C-c C-k'
     Kill the inferior TeX (`TeX-kill-job').

`C-c C-p'
     Print the output from the last `C-c C-r' or `C-c C-b' command
     (`TeX-print').

`C-c C-q'
     Show the printer queue (`TeX-show-print-queue').

   You can pass the current buffer through an inferior TeX by means of
`C-c C-b' (`TeX-buffer').  The formatted output appears in a file in
`/tmp'; to print it, type `C-c C-p' (`TeX-print'). Afterward use `C-c
C-q' (`TeX-show-print-queue') to view the progress of your output
towards being printed.

   The console output from TeX, including any error messages, appears
in a buffer called `*TeX-shell*'.  If TeX gets an error, you can switch
to this buffer and feed it input (this works as in Shell mode; *note
Interactive Shell::.).  Without switching to this buffer you can scroll
it so that its last line is visible by typing `C-c C-l'.

   Type `C-c C-k' (`TeX-kill-job') to kill the TeX process if you see
that its output is no longer useful.  Using `C-c C-b' or `C-c C-r' also
kills any TeX process still running.

   You can also pass an arbitrary region through an inferior TeX by
typing `C-c C-r' (`TeX-region').  This is tricky, however, because most
files of TeX input contain commands at the beginning to set parameters
and define macros, without which no later part of the file will format
correctly.  To solve this problem, `C-c C-r' allows you to designate a
part of the file as containing essential commands; it is included before
the specified region as part of the input to TeX.  The designated part
of the file is called the "header".

   To indicate the bounds of the header in Plain TeX mode, you insert
two special strings in the file.  Insert `%**start of header' before the
header, and `%**end of header' after it.  Each string must appear
entirely on one line, but there may be other text on the line before or
after.  The lines containing the two strings are included in the header.
If `%**start of header' does not appear within the first 100 lines of
the buffer, `C-c C-r' assumes that there is no header.

   In LaTeX mode, the header begins with `\documentstyle' and ends with
`\begin{document}'.  These are commands that LaTeX requires you to use
in any case, so nothing special needs to be done to identify the header.

   Entering either kind of TeX mode calls with no arguments the value of
the variable `text-mode-hook', if that value exists and is not `nil';
then it does the same with the variable `TeX-mode-hook'. Finally it
does the same with either `plain-TeX-mode-hook' or `LaTeX-mode-hook'.


File: emacs,  Node: Texinfo Mode,  Next: Outline Mode,  Prev: TeX Mode,  Up: Text Mode

Texinfo Mode
------------

   Texinfo is a documentation system that uses a single source file to
produce both on-line information and printed output.  This means that
instead of writing two different documents, one for the on-line help or
other on-line information and the other for a typeset manual or other
printed work, you need write only one document.  When the work is
revised, you need revise only one document.  (You can read the on-line
information, known as an "Info file", with an Info
documentation-reading program.  *note info: (info)Top, for more
information about Info.)  Texinfo is the format in which documentation
for GNU utilities and libraries is written.

   Texinfo mode provides special features for working with Texinfo files
including utilities to construct Info menus and pointers automatically,
keybindings to insert frequently used formatting commands, and
keybindings for commands to format both for Info and for printing.

   Texinfo mode is described in *Note Using Texinfo Mode: (
texinfo)Texinfo Mode.


File: emacs,  Node: Outline Mode,  Prev: Texinfo Mode,  Up: Text Mode

Outline Mode
------------

   Outline mode is a major mode much like Text mode but intended for
editing outlines.  It allows you to make parts of the text temporarily
invisible so that you can see just the overall structure of the
outline.  Type `M-x outline-mode' to turn on Outline mode in the
current buffer.

   Entering Outline mode calls with no arguments the value of the
variable `text-mode-hook', if that value exists and is not `nil'; then
it does the same with the variable `outline-mode-hook'.

   When a line is invisible in outline mode, it does not appear on the
screen.  The screen appears exactly as if the invisible line were
deleted, except that an ellipsis (three periods in a row) appears at
the end of the previous visible line (only one ellipsis no matter how
many invisible lines follow).

   All editing commands treat the text of the invisible line as part of
the previous visible line.  For example, `C-n' moves onto the next
visible line.  Killing an entire visible line, including its
terminating newline, really kills all the following invisible lines
along with it; yanking it all back yanks the invisible lines and they
remain invisible.

* Menu:

* Format: Outline Format.	  What the text of an outline looks like.
* Motion: Outline Motion.	  Special commands for moving through outlines.
* Visibility: Outline Visibility. Commands to control what is visible.


File: emacs,  Node: Outline Format,  Next: Outline Motion,  Prev: Outline Mode,  Up: Outline Mode

Format of Outlines
..................

   Outline mode assumes that the lines in the buffer are of two types:
"heading lines" and "body lines".  A heading line represents a topic in
the outline.  Heading lines start with one or more stars; the number of
stars determines the depth of the heading in the outline structure. 
Thus, a heading line with one star is a major topic; all the heading
lines with two stars between it and the next one-star heading are its
subtopics; and so on.  Any line that is not a heading line is a body
line.  Body lines belong to the preceding heading line.  Here is an
example:

     * Food
     
     This is the body,
     which says something about the topic of food.
     
     ** Delicious Food
     
     This is the body of the second-level header.
     
     ** Distasteful Food
     
     This could have
     a body too, with
     several lines.
     
     *** Dormitory Food
     
     * Shelter
     
     A second first-level topic with its header line.

   A heading line together with all following body lines is called
collectively an "entry".  A heading line together with all following
deeper heading lines and their body lines is called a "subtree".

   You can customize the criterion for distinguishing heading lines by
setting the variable `outline-regexp'.  Any line whose beginning has a
match for this regexp is considered a heading line. Matches that start
within a line (not at the beginning) do not count. The length of the
matching text determines the level of the heading; longer matches make
a more deeply nested level.  Thus, for example, if a text formatter has
commands `@chapter', `@section' and `@subsection' to divide the
document into chapters and sections, you could make those lines count
as heading lines by setting `outline-regexp' to
`"@chap\\|@\\(sub\\)*section"'. Note the trick: the two words `chapter'
and `section' are equally long, but by defining the regexp to match
only `chap' we ensure that the length of the text matched on a chapter
heading is shorter, so that Outline mode will know that sections are
contained in chapters. This works as long as no other command starts
with `@chap'.

   Outline mode makes a line invisible by changing the newline before it
into an ASCII Control-M (code 015).  Most editing commands that work on
lines treat an invisible line as part of the previous line because,
strictly speaking, it is part of that line, since there is no longer a
newline in between.  When you save the file in Outline mode, Control-M
characters are saved as newlines, so the invisible lines become ordinary
lines in the file.  But saving does not change the visibility status of
a line inside Emacs.


File: emacs,  Node: Outline Motion,  Next: Outline Visibility,  Prev: Outline Format,  Up: Outline Mode

Outline Motion Commands
.......................

   There are some special motion commands in Outline mode that move
backward and forward to heading lines.

`C-c C-n'
     Move point to the next visible heading line
     (`outline-next-visible-heading').

`C-c C-p'
     Move point to the previous visible heading line
     (`outline-previous-visible-heading').

`C-c C-f'
     Move point to the next visible heading line at the same level as
     the one point is on (`outline-forward-same-level').

`C-c C-b'
     Move point to the previous visible heading line at the same level
     (`outline-backward-same-level').

`C-c C-u'
     Move point up to a lower-level (more inclusive) visible heading
     line (`outline-up-heading').

   `C-c C-n' (`next-visible-heading') moves down to the next heading
line.  `C-c C-p' (`previous-visible-heading') moves similarly backward.
 Both accept numeric arguments as repeat counts.  The names emphasize
that invisible headings are skipped, but this is not really a special
feature.  All editing commands that look for lines ignore the invisible
lines automatically.

   More advanced motion commands understand the levels of headings. The
two commands, `C-c C-f' (`outline-forward-same-level') and `C-c C-b'
(`outline-backward-same-level'), move from one heading line to another
visible heading at the same depth in the outline.  `C-c C-u'
(`outline-up-heading') moves backward to another heading that is less
deeply nested.


File: emacs,  Node: Outline Visibility,  Prev: Outline Motion,  Up: Outline Mode

Outline Visibility Commands
...........................

   The other special commands of outline mode are used to make lines
visible or invisible.  Their names all start with `hide' or `show'.
Most of them fall into pairs of opposites.  They are not undoable;
instead, you can undo right past them.  Making lines visible or
invisible is simply not recorded by the undo mechanism.

`M-x hide-body'
     Make all body lines in the buffer invisible.

`M-x show-all'
     Make all lines in the buffer visible.

`C-c C-h'
     Make everything under this heading invisible, not including this
     heading itself (`hide-subtree').

`C-c C-s'
     Make everything under this heading visible, including body,
     subheadings, and their bodies (`show-subtree').

`M-x hide-leaves'
     Make the body of this heading line, and of all its subheadings,
     invisible.

`M-x show-branches'
     Make all subheadings of this heading line, at all levels, visible.

`C-c C-i'
     Make immediate subheadings (one level down) of this heading line
     visible (`show-children').

`M-x hide-entry'
     Make this heading line's body invisible.

`M-x show-entry'
     Make this heading line's body visible.

   Two commands that are exact opposites are `M-x hide-entry' and `M-x
show-entry'.  They are used with point on a heading line, and apply
only to the body lines of that heading.  The subtopics and their bodies
are not affected.

   Two more powerful opposites are `C-c C-h' (`hide-subtree') and `C-c
C-s' (`show-subtree').  Both expect to be used when point is on a
heading line, and both apply to all the lines of that heading's
"subtree": its body, all its subheadings, both direct and indirect, and
all of their bodies.  In other words, the subtree contains everything
following this heading line, up to and not including the next heading of
the same or higher rank.

   Intermediate between a visible subtree and an invisible one is having
all the subheadings visible but none of the body.  There are two
commands for doing this, depending on whether you want to hide the
bodies or make the subheadings visible.  They are `M-x hide-leaves' and
`M-x show-branches'.

   A little weaker than `show-branches' is `C-c C-i' (`show-children').
 It makes just the direct subheadings visible--those one level down. 
Deeper subheadings remain invisible, if they were invisible.

   Two commands have a blanket effect on the whole file.  `M-x
hide-body' makes all body lines invisible, so that you see just the
outline structure. `M-x show-all' makes all lines visible.  These
commands can be thought of as a pair of opposites even though `M-x
show-all' applies to more than just body lines.

   The use of ellipses at the ends of visible lines can be turned off
by setting `selective-display-ellipses' to `nil'.  Then there is no
visible indication of the presence of invisible lines.