XEmacs 21.4.15

[chise/xemacs-chise.git-] / info / texinfo.info-1

This is ../info/texinfo.info, produced by makeinfo version 4.6 from
texinfo.texi.

INFO-DIR-SECTION Texinfo documentation system
START-INFO-DIR-ENTRY
* Texinfo: (texinfo).           The GNU documentation format.
* install-info: (texinfo)Invoking install-info. Updating info/dir entries.
* texi2dvi: (texinfo)Format with texi2dvi.      Printing Texinfo documentation.
* texindex: (texinfo)Format with tex/texindex.  Sorting Texinfo index files.
* makeinfo: (texinfo)makeinfo Preferred.        Translate Texinfo source.
END-INFO-DIR-ENTRY

  This file documents Texinfo, a documentation system that can produce
both on-line information and a printed manual from a single source file.

  Copyright (C) 1988, 90, 91, 92, 93, 95, 96, 97, 98 Free Software
Foundation, Inc.

  This edition is for Texinfo version 3.12.

  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 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 this permission notice may be stated in a
translation approved by the Free Software Foundation.

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File: texinfo.info,  Node: Top,  Next: Copying,  Prev: (dir),  Up: (dir)

Texinfo
*******

Texinfo is a documentation system that uses a single source file to
produce both on-line information and printed output.

  The first part of this master menu lists the major nodes in this Info
document, including the @-command and concept indices.  The rest of the
menu lists all the lower level nodes in the document.

  This is Edition 3.12 of the Texinfo documentation, 27 February 1998.

* Menu:

* Copying::                     Your rights.
* Overview::                    Texinfo in brief.
* Texinfo Mode::                How to use Texinfo mode.
* Beginning a File::            What is at the beginning of a Texinfo file?
* Ending a File::               What is at the end of a Texinfo file?
* Structuring::                 How to create chapters, sections, subsections,
                                  appendices, and other parts.
* Nodes::                       How to write nodes.
* Menus::                       How to write menus.
* Cross References::            How to write cross references.
* Marking Text::                How to mark words and phrases as code,
                                  keyboard input, meta-syntactic
                                  variables, and the like.
* Quotations and Examples::     How to write quotations, examples, etc.
* Lists and Tables::            How to write lists and tables.
* Indices::                     How to create indices.
* Insertions::                  How to insert @-signs, braces, etc.
* Breaks::                      How to force and prevent line and page breaks.
* Definition Commands::         How to describe functions and the like
                                  in a uniform manner.
* Footnotes::                   How to write footnotes.
* Conditionals::                How to specify text for either TeX or Info.
* Macros::                      Defining new Texinfo commands.
* Format/Print Hardcopy::       How to convert a Texinfo file to a file
                                  for printing and how to print that file.
* Create an Info File::         Convert a Texinfo file into an Info file.
* Install an Info File::        Make an Info file accessible to users.
* Command List::                All the Texinfo @-commands.
* Tips::                        Hints on how to write a Texinfo document.
* Sample Texinfo File::         A sample Texinfo file to look at.
* Sample Permissions::          Tell readers they have the right to copy
                                  and distribute.
* Include Files::               How to incorporate other Texinfo files.
* Headings::                    How to write page headings and footings.
* Catching Mistakes::           How to find formatting mistakes.
* Refilling Paragraphs::        All about paragraph refilling.
* Command Syntax::              A description of @-Command syntax.
* Obtaining TeX::               How to Obtain TeX.
* Command and Variable Index::  A menu containing commands and variables.
* Concept Index::               A menu covering many topics.


 --- The Detailed Node Listing ---

Overview of Texinfo

* Using Texinfo::               Create a conventional printed book
                                  or an Info file.
* Info Files::                  What is an Info file?
* Printed Books::               Characteristics of a printed book or manual.
* Formatting Commands::         @-commands are used for formatting.
* Conventions::                 General rules for writing a Texinfo file.
* Comments::                    How to write comments and mark regions that
                                  the formatting commands will ignore.
* Minimum::                     What a Texinfo file must have.
* Six Parts::                   Usually, a Texinfo file has six parts.
* Short Sample::                A short sample Texinfo file.
* Acknowledgements::

Using Texinfo Mode

* Texinfo Mode Overview::       How Texinfo mode can help you.
* Emacs Editing::               Texinfo mode adds to GNU Emacs' general
                                  purpose editing features.
* Inserting::                   How to insert frequently used @-commands.
* Showing the Structure::       How to show the structure of a file.
* Updating Nodes and Menus::    How to update or create new nodes and menus.
* Info Formatting::             How to format for Info.
* Printing::                    How to format and print part or all of a file.
* Texinfo Mode Summary::        Summary of all the Texinfo mode commands.

Updating Nodes and Menus

* Updating Commands::           Five major updating commands.
* Updating Requirements::       How to structure a Texinfo file for
                                  using the updating command.
* Other Updating Commands::     How to indent descriptions, insert
                                  missing nodes lines, and update
                                  nodes in sequence.

Beginning a Texinfo File

* Four Parts::                  Four parts begin a Texinfo file.
* Sample Beginning::            Here is a sample beginning for a Texinfo file.
* Header::                      The very beginning of a Texinfo file.
* Info Summary and Permissions::  Summary and copying permissions for Info.
* Titlepage & Copyright Page::  Creating the title and copyright pages.
* The Top Node::                Creating the `Top' node and master menu.
* Software Copying Permissions::  Ensure that you and others continue to
                                  have the right to use and share software.

The Texinfo File Header

* First Line::                  The first line of a Texinfo file.
* Start of Header::             Formatting a region requires this.
* setfilename::                 Tell Info the name of the Info file.
* settitle::                    Create a title for the printed work.
* setchapternewpage::           Start chapters on right-hand pages.
* paragraphindent::             An option to specify paragraph indentation.
* End of Header::               Formatting a region requires this.

The Title and Copyright Pages

* titlepage::                   Create a title for the printed document.
* titlefont center sp::         The `@titlefont', `@center',
                                  and `@sp' commands.
* title subtitle author::       The `@title', `@subtitle',
                                  and `@author' commands.
* Copyright & Permissions::     How to write the copyright notice and
                                  include copying permissions.
* end titlepage::               Turn on page headings after the title and
                                  copyright pages.
* headings on off::             An option for turning headings on and off
                                  and double or single sided printing.

The `Top' Node and Master Menu

* Title of Top Node::           Sketch what the file is about.
* Master Menu Parts::           A master menu has three or more parts.

Ending a Texinfo File

* Printing Indices & Menus::    How to print an index in hardcopy and
                                  generate index menus in Info.
* Contents::                    How to create a table of contents.
* File End::                    How to mark the end of a file.

Chapter Structuring

* Tree Structuring::            A manual is like an upside down tree ...
* Structuring Command Types::   How to divide a manual into parts.
* makeinfo top::                The `@top' command, part of the `Top' node.
* chapter::
* unnumbered & appendix::
* majorheading & chapheading::
* section::
* unnumberedsec appendixsec heading::
* subsection::
* unnumberedsubsec appendixsubsec subheading::
* subsubsection::               Commands for the lowest level sections.
* Raise/lower sections::        How to change commands' hierarchical level.

Nodes

* Two Paths::                   Different commands to structure
                                  Info output and printed output.
* Node Menu Illustration::      A diagram, and sample nodes and menus.
* node::                        How to write a node, in detail.
* makeinfo Pointer Creation::   How to create node pointers with `makeinfo'.

The `@node' Command

* Node Names::                  How to choose node and pointer names.
* Writing a Node::              How to write an `@node' line.
* Node Line Tips::              Keep names short.
* Node Line Requirements::      Keep names unique, without @-commands.
* First Node::                  How to write a `Top' node.
* makeinfo top command::        How to use the `@top' command.
* Top Node Summary::            Write a brief description for readers.

Menus

* Menu Location::               Put a menu in a short node.
* Writing a Menu::              What is a menu?
* Menu Parts::                  A menu entry has three parts.
* Less Cluttered Menu Entry::   Two part menu entry.
* Menu Example::                Two and three part menu entries.
* Other Info Files::            How to refer to a different Info file.

Cross References

* References::                  What cross references are for.
* Cross Reference Commands::    A summary of the different commands.
* Cross Reference Parts::       A cross reference has several parts.
* xref::                        Begin a reference with `See' ...
* Top Node Naming::             How to refer to the beginning of another file.
* ref::                         A reference for the last part of a sentence.
* pxref::                       How to write a parenthetical cross reference.
* inforef::                     How to refer to an Info-only file.
* uref::                        How to refer to a uniform resource locator.

`@xref'

* Reference Syntax::            What a reference looks like and requires.
* One Argument::                `@xref' with one argument.
* Two Arguments::               `@xref' with two arguments.
* Three Arguments::             `@xref' with three arguments.
* Four and Five Arguments::     `@xref' with four and five arguments.

Marking Words and Phrases

* Indicating::                  How to indicate definitions, files, etc.
* Emphasis::                    How to emphasize text.

Indicating Definitions, Commands, etc.

* Useful Highlighting::         Highlighting provides useful information.
* code::                        How to indicate code.
* kbd::                         How to show keyboard input.
* key::                         How to specify keys.
* samp::                        How to show a literal sequence of characters.
* var::                         How to indicate a metasyntactic variable.
* file::                        How to indicate the name of a file.
* dfn::                         How to specify a definition.
* cite::                        How to refer to a book that is not in Info.
* url::                         How to indicate a world wide web reference.
* email::                       How to indicate an electronic mail address.

Emphasizing Text

* emph & strong::               How to emphasize text in Texinfo.
* Smallcaps::                   How to use the small caps font.
* Fonts::                       Various font commands for printed output.
* Customized Highlighting::     How to define highlighting commands.

Quotations and Examples

* Block Enclosing Commands::    Use different constructs for
                                  different purposes.
* quotation::                   How to write a quotation.
* example::                     How to write an example in a fixed-width font.
* noindent::                    How to prevent paragraph indentation.
* Lisp Example::                How to illustrate Lisp code.
* smallexample & smalllisp::    Forms for the `@smallbook' option.
* display::                     How to write an example in the current font.
* format::                      How to write an example that does not narrow
                                  the margins.
* exdent::                      How to undo the indentation of a line.
* flushleft & flushright::      How to push text flushleft or flushright.
* cartouche::                   How to draw cartouches around examples.

Lists and Tables

* Introducing Lists::           Texinfo formats lists for you.
* itemize::                     How to construct a simple list.
* enumerate::                   How to construct a numbered list.
* Two-column Tables::           How to construct a two-column table.
* Multi-column Tables::         How to construct generalized tables.

Making a Two-column Table

* table::                       How to construct a two-column table.
* ftable vtable::               Automatic indexing for two-column tables.
* itemx::                       How to put more entries in the first column.

Multi-column Tables

* Multitable Column Widths::    Defining multitable column widths.
* Multitable Rows::             Defining multitable rows, with examples.

Creating Indices

* Index Entries::               Choose different words for index entries.
* Predefined Indices::          Use different indices for different kinds
                                  of entry.
* Indexing Commands::           How to make an index entry.
* Combining Indices::           How to combine indices.
* New Indices::                 How to define your own indices.

Combining Indices

* syncodeindex::                How to merge two indices, using `@code'
                                  font for the merged-from index.
* synindex::                    How to merge two indices, using the
                                  default font of the merged-to index.

Special Insertions

* Braces Atsigns::              How to insert braces, `@'.
* Inserting Space::             How to insert the right amount of space
                                  within a sentence.
* Inserting Accents::           How to insert accents and special characters.
* Dots Bullets::                How to insert dots and bullets.
* TeX and copyright::           How to insert the TeX logo
                                  and the copyright symbol.
* pounds::                      How to insert the pounds currency symbol.
* minus::                       How to insert a minus sign.
* math::                        How to format a mathematical expression.
* Glyphs::                      How to indicate results of evaluation,
                                  expansion of macros, errors, etc.
* Images::                      How to include graphics.

Inserting @ and Braces

* Inserting An Atsign::         How to insert `@'.
* Inserting Braces::            How to insert `{' and `}'.

Inserting Space

* Not Ending a Sentence::       Sometimes a . doesn't end a sentence.
* Ending a Sentence::           Sometimes it does.
* Multiple Spaces::             Inserting multiple spaces.
* dmn::                         How to format a dimension.

Inserting Ellipsis, Dots, and Bullets

* dots::                        How to insert dots ...
* bullet::                      How to insert a bullet.

Inserting TeX and the Copyright Symbol

* tex::                         How to insert the TeX logo.
* copyright symbol::            How to use `@copyright'{}.

Glyphs for Examples

* Glyphs Summary::
* result::                      How to show the result of expression.
* expansion::                   How to indicate an expansion.
* Print Glyph::                 How to indicate printed output.
* Error Glyph::                 How to indicate an error message.
* Equivalence::                 How to indicate equivalence.
* Point Glyph::                 How to indicate the location of point.

Glyphs Summary

* result::
* expansion::
* Print Glyph::
* Error Glyph::
* Equivalence::
* Point Glyph::

Making and Preventing Breaks

* Break Commands::              Cause and prevent splits.
* Line Breaks::                 How to force a single line to use two lines.
* - and hyphenation::           How to tell TeX about hyphenation points.
* w::                           How to prevent unwanted line breaks.
* sp::                          How to insert blank lines.
* page::                        How to force the start of a new page.
* group::                       How to prevent unwanted page breaks.
* need::                        Another way to prevent unwanted page breaks.

Definition Commands

* Def Cmd Template::            How to structure a description using a
                                  definition command.
* Optional Arguments::          How to handle optional and repeated arguments.
* deffnx::                      How to group two or more `first' lines.
* Def Cmds in Detail::          All the definition commands.
* Def Cmd Conventions::         Conventions for writing definitions.
* Sample Function Definition::

The Definition Commands

* Functions Commands::          Commands for functions and similar entities.
* Variables Commands::          Commands for variables and similar entities.
* Typed Functions::             Commands for functions in typed languages.
* Typed Variables::             Commands for variables in typed languages.
* Abstract Objects::            Commands for object-oriented programming.
* Data Types::                  The definition command for data types.

Footnotes

* Footnote Commands::           How to write a footnote in Texinfo.
* Footnote Styles::             Controlling how footnotes appear in Info.

Conditionally Visible Text

* Conditional Commands::        Specifying text for HTML, Info, or TeX.
* Conditional Not Commands::    Specifying text for not HTML, Info, or TeX.
* Raw Formatter Commands::      Using raw TeX or HTML commands.
* set clear value::             Designating which text to format (for
                                  all output formats); and how to set a
                                  flag to a string that you can insert.

`@set', `@clear', and `@value'

* ifset ifclear::               Format a region if a flag is set.
* value::                       Replace a flag with a string.
* value Example::               An easy way to update edition information.

Macros: Defining New Texinfo Commands

* Defining Macros::             Both defining and undefining new commands.
* Invoking Macros::             Using a macro, once you've defined it.

Format and Print Hardcopy

* Use TeX::                     Use TeX to format for hardcopy.
* Format with tex/texindex::    How to format in a shell.
* Format with texi2dvi::        A simpler way to use the shell.
* Print with lpr::              How to print.
* Within Emacs::                How to format and print from an Emacs shell.
* Texinfo Mode Printing::       How to format and print in Texinfo mode.
* Compile-Command::             How to print using Emacs's compile command.
* Requirements Summary::        TeX formatting requirements summary.
* Preparing for TeX::           What you need to do to use TeX.
* Overfull hboxes::             What are and what to do with overfull hboxes.
* smallbook::                   How to print small format books and manuals.
* A4 Paper::                    How to print on European A4 paper.
* Cropmarks and Magnification::  How to print marks to indicate the size
                                of pages and how to print scaled up output.

Creating an Info File

* makeinfo advantages::         `makeinfo' provides better error checking.
* Invoking makeinfo::           How to run `makeinfo' from a shell.
* makeinfo options::            Specify fill-column and other options.
* Pointer Validation::          How to check that pointers point somewhere.
* makeinfo in Emacs::           How to run `makeinfo' from Emacs.
* texinfo-format commands::     Two Info formatting commands written
                                  in Emacs Lisp are an alternative
                                  to `makeinfo'.
* Batch Formatting::            How to format for Info in Emacs Batch mode.
* Tag and Split Files::         How tagged and split files help Info
                                  to run better.

Installing an Info File

* Directory file::              The top level menu for all Info files.
* New Info File::               Listing a new info file.
* Other Info Directories::      How to specify Info files that are
                                  located in other directories.
* Installing Dir Entries::      How to specify what menu entry to add
                                  to the Info directory.
* Invoking install-info::       `install-info' options.

Sample Permissions

* Inserting Permissions::       How to put permissions in your document.
* ifinfo Permissions::          Sample `ifinfo' copying permissions.
* Titlepage Permissions::       Sample Titlepage copying permissions.

Include Files

* Using Include Files::         How to use the `@include' command.
* texinfo-multiple-files-update::  How to create and update nodes and
                                  menus when using included files.
* Include File Requirements::   What `texinfo-multiple-files-update' expects.
* Sample Include File::         A sample outer file with included files
                                  within it; and a sample included file.
* Include Files Evolution::     How use of the `@include' command
                                  has changed over time.

Page Headings

* Headings Introduced::         Conventions for using page headings.
* Heading Format::              Standard page heading formats.
* Heading Choice::              How to specify the type of page heading.
* Custom Headings::             How to create your own headings and footings.

Formatting Mistakes

* makeinfo Preferred::          `makeinfo' finds errors.
* Debugging with Info::         How to catch errors with Info formatting.
* Debugging with TeX::          How to catch errors with TeX formatting.
* Using texinfo-show-structure::  How to use `texinfo-show-structure'.
* Using occur::                 How to list all lines containing a pattern.
* Running Info-Validate::       How to find badly referenced nodes.

Finding Badly Referenced Nodes

* Using Info-validate::         How to run `Info-validate'.
* Unsplit::                     How to create an unsplit file.
* Tagifying::                   How to tagify a file.
* Splitting::                   How to split a file manually.

How to Obtain TeX

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File: texinfo.info,  Node: Copying,  Next: Overview,  Prev: Top,  Up: Top

Texinfo Copying Conditions
**************************

The programs currently being distributed that relate to Texinfo include
portions of GNU Emacs, plus other separate programs (including
`makeinfo', `info', `texindex', and `texinfo.tex').  These programs are
"free"; this means that everyone is free to use them and free to
redistribute them on a free basis.  The Texinfo-related programs are
not in the public domain; they are copyrighted and there are
restrictions on their distribution, but these restrictions are designed
to permit everything that a good cooperating citizen would want to do.
What is not allowed is to try to prevent others from further sharing
any version of these programs that they might get from you.

  Specifically, we want to make sure that you have the right to give
away copies of the programs that relate to Texinfo, that you receive
source code or else can get it if you want it, that you can change these
programs or use pieces of them in new free programs, and that you know
you can do these things.

  To make sure that everyone has such rights, we have to forbid you to
deprive anyone else of these rights.  For example, if you distribute
copies of the Texinfo related programs, you must give the recipients all
the rights that you have.  You must make sure that they, too, receive or
can get the source code.  And you must tell them their rights.

  Also, for our own protection, we must make certain that everyone finds
out that there is no warranty for the programs that relate to Texinfo.
If these programs are modified by someone else and passed on, we want
their recipients to know that what they have is not what we distributed,
so that any problems introduced by others will not reflect on our
reputation.

  The precise conditions of the licenses for the programs currently
being distributed that relate to Texinfo are found in the General Public
Licenses that accompany them.

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File: texinfo.info,  Node: Overview,  Next: Texinfo Mode,  Prev: Copying,  Up: Top

Overview of Texinfo
*******************

"Texinfo"(1) (*note Overview-Footnote-1::) 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.)

* Menu:

* Using Texinfo::               Create a conventional printed book
                                  or an Info file.
* Info Files::                  What is an Info file?
* Printed Books::               Characteristics of a printed book or manual.
* Formatting Commands::         @-commands are used for formatting.
* Conventions::                 General rules for writing a Texinfo file.
* Comments::                    How to write comments and mark regions that
                                  the formatting commands will ignore.
* Minimum::                     What a Texinfo file must have.
* Six Parts::                   Usually, a Texinfo file has six parts.
* Short Sample::                A short sample Texinfo file.
* Acknowledgements::

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File: texinfo.info,  Node: Overview-Footnotes,  Up: Overview

  (1) Note that the first syllable of "Texinfo" is pronounced like
"speck", not "hex".  This odd pronunciation is derived from, but is not
the same as, the pronunciation of TeX.  In the word TeX, the `X' is
actually the Greek letter "chi" rather than the English letter "ex".
Pronounce TeX as if the `X' were the last sound in the name `Bach'; but
pronounce Texinfo as if the `x' were a `k'.  Spell "Texinfo" with a
capital "T" and write the other letters in lower case.

\1f
File: texinfo.info,  Node: Using Texinfo,  Next: Info Files,  Prev: Overview,  Up: Overview

Using Texinfo
=============

  Using Texinfo, you can create a printed document with the normal
features of a book, including chapters, sections, cross references, and
indices.  From the same Texinfo source file, you can create a
menu-driven, on-line Info file with nodes, menus, cross references, and
indices.  You can, if you wish, make the chapters and sections of the
printed document correspond to the nodes of the on-line information;
and you use the same cross references and indices for both the Info
file and the printed work.  `The XEmacs User's Manual' is a good
example of a Texinfo file, as is this manual.

  To make a printed document, you process a Texinfo source file with the
TeX typesetting program.  This creates a DVI file that you can typeset
and print as a book or report.  (Note that the Texinfo language is
completely different from TeX's usual language, plain TeX.)  If you do
not have TeX, but do have `troff' or `nroff', you can use the
`texi2roff' program instead.

  To make an Info file, you process a Texinfo source file with the
`makeinfo' utility or Emacs's `texinfo-format-buffer' command; this
creates an Info file that you can install on-line.

  TeX and `texi2roff' work with many types of printers; similarly, Info
works with almost every type of computer terminal.  This power makes
Texinfo a general purpose system, but brings with it a constraint,
which is that a Texinfo file may contain only the customary
"typewriter" characters (letters, numbers, spaces, and punctuation
marks) but no special graphics.

  A Texinfo file is a plain ASCII file containing text and "@-commands"
(words preceded by an `@') that tell the typesetting and formatting
programs what to do.  You may edit a Texinfo file with any text editor;
but it is especially convenient to use GNU Emacs since that editor has
a special mode, called Texinfo mode, that provides various
Texinfo-related features.  (*Note Texinfo Mode::.)

  Before writing a Texinfo source file, you should become familiar with
the Info documentation reading program and learn about nodes, menus,
cross references, and the rest.  (*note info: (info)Top, for more
information.)

  You can use Texinfo to create both on-line help and printed manuals;
moreover, Texinfo is freely redistributable.  For these reasons, Texinfo
is the format in which documentation for GNU utilities and libraries is
written.

\1f
File: texinfo.info,  Node: Info Files,  Next: Printed Books,  Prev: Using Texinfo,  Up: Overview

Info files
==========

An Info file is a Texinfo file formatted so that the Info documentation
reading program can operate on it.  (`makeinfo' and
`texinfo-format-buffer' are two commands that convert a Texinfo file
into an Info file.)

  Info files are divided into pieces called "nodes", each of which
contains the discussion of one topic.  Each node has a name, and
contains both text for the user to read and pointers to other nodes,
which are identified by their names.  The Info program displays one node
at a time, and provides commands with which the user can move to other
related nodes.

  *note info: (info)Top, for more information about using Info.

  Each node of an Info file may have any number of child nodes that
describe subtopics of the node's topic.  The names of child nodes are
listed in a "menu" within the parent node; this allows you to use
certain Info commands to move to one of the child nodes.  Generally, an
Info file is organized like a book.  If a node is at the logical level
of a chapter, its child nodes are at the level of sections; likewise,
the child nodes of sections are at the level of subsections.

  All the children of any one parent are linked together in a
bidirectional chain of `Next' and `Previous' pointers.  The `Next'
pointer provides a link to the next section, and the `Previous' pointer
provides a link to the previous section.  This means that all the nodes
that are at the level of sections within a chapter are linked together.
Normally the order in this chain is the same as the order of the
children in the parent's menu.  Each child node records the parent node
name as its `Up' pointer.  The last child has no `Next' pointer, and the
first child has the parent both as its `Previous' and as its `Up'
pointer.(1) (*note Info Files-Footnote-1::)

  The book-like structuring of an Info file into nodes that correspond
to chapters, sections, and the like is a matter of convention, not a
requirement.  The `Up', `Previous', and `Next' pointers of a node can
point to any other nodes, and a menu can contain any other nodes.
Thus, the node structure can be any directed graph.  But it is usually
more comprehensible to follow a structure that corresponds to the
structure of chapters and sections in a printed book or report.

  In addition to menus and to `Next', `Previous', and `Up' pointers,
Info provides pointers of another kind, called references, that can be
sprinkled throughout the text.  This is usually the best way to
represent links that do not fit a hierarchical structure.

  Usually, you will design a document so that its nodes match the
structure of chapters and sections in the printed output.  But
occasionally there are times when this is not right for the material
being discussed.  Therefore, Texinfo uses separate commands to specify
the node structure for the Info file and the section structure for the
printed output.

  Generally, you enter an Info file through a node that by convention is
named `Top'.  This node normally contains just a brief summary of the
file's purpose, and a large menu through which the rest of the file is
reached.  From this node, you can either traverse the file
systematically by going from node to node, or you can go to a specific
node listed in the main menu, or you can search the index menus and then
go directly to the node that has the information you want.
Alternatively, with the standalone Info program, you can specify
specific menu items on the command line (*note Top: (info)Top.).

  If you want to read through an Info file in sequence, as if it were a
printed manual, you can hit <SPC> repeatedly, or you get the whole file
with the advanced Info command `g *'.  (*note Advanced Info commands:
(info)Expert.)

  The `dir' file in the `info' directory serves as the departure point
for the whole Info system.  From it, you can reach the `Top' nodes of
each of the documents in a complete Info system.

\1f
File: texinfo.info,  Node: Info Files-Footnotes,  Up: Info Files

  (1) In some documents, the first child has no `Previous' pointer.
Occasionally, the last child has the node name of the next following
higher level node as its `Next' pointer.

\1f
File: texinfo.info,  Node: Printed Books,  Next: Formatting Commands,  Prev: Info Files,  Up: Overview

Printed Books
=============

A Texinfo file can be formatted and typeset as a printed book or manual.
To do this, you need TeX, a powerful, sophisticated typesetting program
written by Donald Knuth.(1) (*note Printed Books-Footnote-1::)

  A Texinfo-based book is similar to any other typeset, printed work: it
can have a title page, copyright page, table of contents, and preface,
as well as chapters, numbered or unnumbered sections and subsections,
page headers, cross references, footnotes, and indices.

  You can use Texinfo to write a book without ever having the intention
of converting it into on-line information.  You can use Texinfo for
writing a printed novel, and even to write a printed memo, although
this latter application is not recommended since electronic mail is so
much easier.

  TeX is a general purpose typesetting program.  Texinfo provides a
file called `texinfo.tex' that contains information (definitions or
"macros") that TeX uses when it typesets a Texinfo file.
(`texinfo.tex' tells TeX how to convert the Texinfo @-commands to TeX
commands, which TeX can then process to create the typeset document.)
`texinfo.tex' contains the specifications for printing a document.

  Most often, documents are printed on 8.5 inch by 11 inch pages (216mm
by 280mm; this is the default size), but you can also print for 7 inch
by 9.25 inch pages (178mm by 235mm; the `@smallbook' size) or on
European A4 size paper (`@afourpaper').  (*Note Printing "Small" Books:
smallbook.  Also, see *Note Printing on A4 Paper: A4 Paper.)

  By changing the parameters in `texinfo.tex', you can change the size
of the printed document.  In addition, you can change the style in
which the printed document is formatted; for example, you can change the
sizes and fonts used, the amount of indentation for each paragraph, the
degree to which words are hyphenated, and the like.  By changing the
specifications, you can make a book look dignified, old and serious, or
light-hearted, young and cheery.

  TeX is freely distributable.  It is written in a superset of Pascal
called WEB and can be compiled either in Pascal or (by using a
conversion program that comes with the TeX distribution) in C.  (*Note
TeX Mode: (xemacs)TeX Mode, for information about TeX.)

  TeX is very powerful and has a great many features.  Because a
Texinfo file must be able to present information both on a
character-only terminal in Info form and in a typeset book, the
formatting commands that Texinfo supports are necessarily limited.

  *Note How to Obtain TeX: Obtaining TeX.

\1f
File: texinfo.info,  Node: Printed Books-Footnotes,  Up: Printed Books

  (1) You can also use the `texi2roff' program if you do not have TeX;
since Texinfo is designed for use with TeX, `texi2roff' is not
described here.  `texi2roff' is not part of the standard GNU
distribution.

\1f
File: texinfo.info,  Node: Formatting Commands,  Next: Conventions,  Prev: Printed Books,  Up: Overview

@-commands
==========

In a Texinfo file, the commands that tell TeX how to typeset the
printed manual and tell `makeinfo' and `texinfo-format-buffer' how to
create an Info file are preceded by `@'; they are called "@-commands".
For example, `@node' is the command to indicate a node and `@chapter'
is the command to indicate the start of a chapter.

     *Please note:* All the @-commands, with the exception of the
     `@TeX{}' command, must be written entirely in lower case.

  The Texinfo @-commands are a strictly limited set of constructs.  The
strict limits make it possible for Texinfo files to be understood both
by TeX and by the code that converts them into Info files.  You can
display Info files on any terminal that displays alphabetic and numeric
characters.  Similarly, you can print the output generated by TeX on a
wide variety of printers.

  Depending on what they do or what arguments(1) (*note Formatting
Commands-Footnote-1::) they take, you need to write @-commands on lines
of their own or as part of sentences:

   * Write a command such as `@noindent' at the beginning of a line as
     the only text on the line.  (`@noindent' prevents the beginning of
     the next line from being indented as the beginning of a paragraph.)

   * Write a command such as `@chapter' at the beginning of a line
     followed by the command's arguments, in this case the chapter
     title, on the rest of the line.  (`@chapter' creates chapter
     titles.)

   * Write a command such as `@dots{}' wherever you wish but usually
     within a sentence. (`@dots{}' creates dots ...)

   * Write a command such as `@code{SAMPLE-CODE}' wherever you wish
     (but usually within a sentence) with its argument, SAMPLE-CODE in
     this example, between the braces.  (`@code' marks text as being
     code.)

   * Write a command such as `@example' at the beginning of a line of
     its own; write the body-text on following lines; and write the
     matching `@end' command, `@end example' in this case, at the
     beginning of a line of its own after the body-text. (`@example'
     ... `@end example' indents and typesets body-text as an example.)

As a general rule, a command requires braces if it mingles among other
text; but it does not need braces if it starts a line of its own.  The
non-alphabetic commands, such as `@:', are exceptions to the rule; they
do not need braces.

  As you gain experience with Texinfo, you will rapidly learn how to
write the different commands: the different ways to write commands make
it easier to write and read Texinfo files than if all commands followed
exactly the same syntax.  (For details about @-command syntax, see
*Note @-Command Syntax: Command Syntax.)

\1f
File: texinfo.info,  Node: Formatting Commands-Footnotes,  Up: Formatting Commands

  (1) The word "argument" comes from the way it is used in mathematics
and does not refer to a disputation between two people; it refers to the
information presented to the command.  According to the `Oxford English
Dictionary', the word derives from the Latin for "to make clear,
prove"; thus it came to mean `the evidence offered as proof', which is
to say, `the information offered', which led to its mathematical
meaning.  In its other thread of derivation, the word came to mean `to
assert in a manner against which others may make counter assertions',
which led to the meaning of `argument' as a disputation.

\1f
File: texinfo.info,  Node: Conventions,  Next: Comments,  Prev: Formatting Commands,  Up: Overview

General Syntactic Conventions
=============================

All printable ASCII characters except `@', `{' and `}' can appear in a
Texinfo file and stand for themselves.  `@' is the escape character
which introduces commands.  `{' and `}' should be used only to surround
arguments to certain commands.  To put one of these special characters
into the document, put an `@' character in front of it, like this:
`@@', `@{', and `@}'.

  It is customary in TeX to use doubled single-quote characters to
begin and end quotations: ` ` and ' ' (but without a space between the
two single-quote characters).  This convention should be followed in
Texinfo files.  TeX converts doubled single-quote characters to left-
and right-hand doubled quotation marks and Info converts doubled
single-quote characters to ASCII double-quotes: ` ` and ' ' to " .

  Use three hyphens in a row, `---', for a dash--like this.  In TeX, a
single or double hyphen produces a printed dash that is shorter than
the usual typeset dash. Info reduces three hyphens to two for display
on the screen.

  To prevent a paragraph from being indented in the printed manual, put
the command `@noindent' on a line by itself before the paragraph.

  If you mark off a region of the Texinfo file with the `@iftex' and
`@end iftex' commands, that region will appear only in the printed
copy; in that region, you can use certain commands borrowed from plain
TeX that you cannot use in Info.  Likewise, if you mark off a region
with the `@ifinfo' and `@end ifinfo' commands, that region will appear
only in the Info file; in that region, you can use Info commands that
you cannot use in TeX.  Similarly for `@ifhtml ... @end ifhtml',
`@ifnothtml ... @end ifnothtml', `@ifnotinfo ... @end ifnotinfo',
`@ifnottex ... @end ifnottex', *Note Conditionals::.

     *Caution:* Do not use tabs in a Texinfo file!  TeX uses
     variable-width fonts, which means that it cannot predefine a tab
     to work in all circumstances.  Consequently, TeX treats tabs like
     single spaces, and that is not what they look like.  Furthermore,
     `makeinfo' does nothing special with tabs, and thus a tab character
     in your input file may appear differently in the output.

     To avoid this problem, Texinfo mode causes GNU Emacs to insert
     multiple spaces when you press the <TAB> key.

     Also, you can run `untabify' in Emacs to convert tabs in a region
     to multiple spaces.

     Don't use tabs.

\1f
File: texinfo.info,  Node: Comments,  Next: Minimum,  Prev: Conventions,  Up: Overview

Comments
========

You can write comments in a Texinfo file that will not appear in either
the Info file or the printed manual by using the `@comment' command
(which may be abbreviated to `@c').  Such comments are for the person
who reads the Texinfo file.  All the text on a line that follows either
`@comment' or `@c' is a comment; the rest of the line does not appear
in either the Info file or the printed manual. (Often, you can write
the `@comment' or `@c' in the middle of a line, and only the text that
follows after the `@comment' or `@c' command does not appear; but some
commands, such as `@settitle' and `@setfilename', work on a whole line.
You cannot use `@comment' or `@c' in a line beginning with such a
command.)

  You can write long stretches of text that will not appear in either
the Info file or the printed manual by using the `@ignore' and `@end
ignore' commands.  Write each of these commands on a line of its own,
starting each command at the beginning of the line.  Text between these
two commands does not appear in the processed output.  You can use
`@ignore' and `@end ignore' for writing comments.  Often, `@ignore' and
`@end ignore' is used to enclose a part of the copying permissions that
applies to the Texinfo source file of a document, but not to the Info
or printed version of the document.

\1f
File: texinfo.info,  Node: Minimum,  Next: Six Parts,  Prev: Comments,  Up: Overview

What a Texinfo File Must Have
=============================

By convention, the names of Texinfo files end with one of the
extensions `.texinfo', `.texi', or `.tex'.  The longer extension is
preferred since it describes more clearly to a human reader the nature
of the file.  The shorter extensions are for operating systems that
cannot handle long file names.

  In order to be made into a printed manual and an Info file, a Texinfo
file *must* begin with lines like this:

     \input texinfo
     @setfilename INFO-FILE-NAME
     @settitle NAME-OF-MANUAL

The contents of the file follow this beginning, and then you *must* end
a Texinfo file with a line like this:

     @bye

The `\input texinfo' line tells TeX to use the `texinfo.tex' file,
which tells TeX how to translate the Texinfo @-commands into TeX
typesetting commands.  (Note the use of the backslash, `\'; this is
correct for TeX.)  The `@setfilename' line provides a name for the Info
file and tells TeX to open auxiliary files.  The `@settitle' line
specifies a title for the page headers (or footers) of the printed
manual.

  The `@bye' line at the end of the file on a line of its own tells the
formatters that the file is ended and to stop formatting.

  Usually, you will not use quite such a spare format, but will include
mode setting and start-of-header and end-of-header lines at the
beginning of a Texinfo file, like this:

     \input texinfo   @c -*-texinfo-*-
     @c %**start of header
     @setfilename INFO-FILE-NAME
     @settitle NAME-OF-MANUAL
     @c %**end of header

In the first line, `-*-texinfo-*-' causes Emacs to switch into Texinfo
mode when you edit the file.

  The `@c' lines which surround the `@setfilename' and `@settitle'
lines are optional, but you need them in order to run TeX or Info on
just part of the file.  (*Note Start of Header::, for more information.)

  Furthermore, you will usually provide a Texinfo file with a title
page, indices, and the like.  But the minimum, which can be useful for
short documents, is just the three lines at the beginning and the one
line at the end.

\1f
File: texinfo.info,  Node: Six Parts,  Next: Short Sample,  Prev: Minimum,  Up: Overview

Six Parts of a Texinfo File
===========================

Generally, a Texinfo file contains more than the minimal beginning and
end--it usually contains six parts:

1. Header
     The "Header" names the file, tells TeX which definitions' file to
     use, and performs other "housekeeping" tasks.

2. Summary Description and Copyright
     The "Summary Description and Copyright" segment describes the
     document and contains the copyright notice and copying permissions
     for the Info file.  The segment must be enclosed between `@ifinfo'
     and `@end ifinfo' commands so that the formatters place it only in
     the Info file.

3. Title and Copyright
     The "Title and Copyright" segment contains the title and copyright
     pages and copying permissions for the printed manual.  The segment
     must be enclosed between `@titlepage' and `@end titlepage'
     commands.  The title and copyright page appear only in the printed
     manual.

4. `Top' Node and Master Menu
     The "Master Menu" contains a complete menu of all the nodes in the
     whole Info file.  It appears only in the Info file, in the `Top'
     node.

5. Body
     The "Body" of the document may be structured like a traditional
     book or encyclopedia or it may be free form.

6. End
     The "End" contains commands for printing indices and generating
     the table of contents, and the `@bye' command on a line of its own.

\1f
File: texinfo.info,  Node: Short Sample,  Next: Acknowledgements,  Prev: Six Parts,  Up: Overview

A Short Sample Texinfo File
===========================

Here is a complete but very short Texinfo file, in six parts.  The first
three parts of the file, from `\input texinfo' through to `@end
titlepage', look more intimidating than they are.  Most of the material
is standard boilerplate; when you write a manual, simply insert the
names for your own manual in this segment. (*Note Beginning a File::.)

In the following, the sample text is _indented_; comments on it are
not.  The complete file, without any comments, is shown in *Note Sample
Texinfo File::.

Part 1: Header
--------------

The header does not appear in either the Info file or the printed
output.  It sets various parameters, including the name of the Info
file and the title used in the header.

     \input texinfo   @c -*-texinfo-*-
     @c %**start of header
     @setfilename sample.info
     @settitle Sample Document
     @c %**end of header
     
     @setchapternewpage odd

Part 2: Summary Description and Copyright
-----------------------------------------

The summary description and copyright segment does not appear in the
printed document.

     @ifinfo
     This is a short example of a complete Texinfo file.
     
     Copyright @copyright{} 1990 Free Software Foundation, Inc.
     @end ifinfo

Part 3: Titlepage and Copyright
-------------------------------

The titlepage segment does not appear in the Info file.

     @titlepage
     @sp 10
     @comment The title is printed in a large font.
     @center @titlefont{Sample Title}
     
     @c The following two commands start the copyright page.
     @page
     @vskip 0pt plus 1filll
     Copyright @copyright{} 1990 Free Software Foundation, Inc.
     @end titlepage

Part 4: `Top' Node and Master Menu
----------------------------------

The `Top' node contains the master menu for the Info file.  Since a
printed manual uses a table of contents rather than a menu, the master
menu appears only in the Info file.

     @node    Top,       First Chapter, ,         (dir)
     @comment node-name, next,          previous, up

     @menu
     * First Chapter::    The first chapter is the
                          only chapter in this sample.
     * Concept Index::    This index has two entries.
     @end menu

Part 5:  The Body of the Document
---------------------------------

The body segment contains all the text of the document, but not the
indices or table of contents.  This example illustrates a node and a
chapter containing an enumerated list.

     @node    First Chapter, Concept Index, Top,      Top
     @comment node-name,     next,          previous, up
     @chapter First Chapter
     @cindex Sample index entry
     
     This is the contents of the first chapter.
     @cindex Another sample index entry
     
     Here is a numbered list.
     
     @enumerate
     @item
     This is the first item.
     
     @item
     This is the second item.
     @end enumerate
     
     The @code{makeinfo} and @code{texinfo-format-buffer}
     commands transform a Texinfo file such as this into
     an Info file; and @TeX{} typesets it for a printed
     manual.

Part 6: The End of the Document
-------------------------------

The end segment contains commands both for generating an index in a node
and unnumbered chapter of its own and for generating the table of
contents; and it contains the `@bye' command that marks the end of the
document.

     @node    Concept Index,    ,  First Chapter, Top
     @comment node-name,    next,  previous,      up
     @unnumbered Concept Index
     
     @printindex cp
     
     @contents
     @bye

The Results
-----------

Here is what the contents of the first chapter of the sample look like:


     This is the contents of the first chapter.

     Here is a numbered list.

       1. This is the first item.

       2. This is the second item.

     The `makeinfo' and `texinfo-format-buffer' commands transform a
     Texinfo file such as this into an Info file; and TeX typesets it
     for a printed manual.

\1f
File: texinfo.info,  Node: Acknowledgements,  Prev: Short Sample,  Up: Overview

Acknowledgements
================

Richard M. Stallman wrote Edition 1.0 of this manual.
Robert J. Chassell revised and extended it, starting with Edition 1.1.
Karl Berry made updates for the Texinfo 3.8 and subsequent releases,
starting with Edition 2.22.

  Our thanks go out to all who helped improve this work, particularly to
Franc,ois Pinard and David D. Zuhn, who tirelessly recorded and
reported mistakes and obscurities; our special thanks go to Melissa
Weisshaus for her frequent and often tedious reviews of nearly similar
editions.  Our mistakes are our own.

  Please send suggestions and corrections to:

     Internet address:
         bug-texinfo@gnu.org

Please include the manual's edition number and update date in your
messages.

\1f
File: texinfo.info,  Node: Texinfo Mode,  Next: Beginning a File,  Prev: Overview,  Up: Top

Using Texinfo Mode
******************

You may edit a Texinfo file with any text editor you choose.  A Texinfo
file is no different from any other ASCII file.  However, GNU Emacs
comes with a special mode, called Texinfo mode, that provides  Emacs
commands and tools to help ease your work.

  This chapter describes features of GNU Emacs' Texinfo mode but not any
features of the Texinfo formatting language.  If you are reading this
manual straight through from the beginning, you may want to skim through
this chapter briefly and come back to it after reading succeeding
chapters which describe the Texinfo formatting language in detail.

* Menu:

* Texinfo Mode Overview::       How Texinfo mode can help you.
* Emacs Editing::               Texinfo mode adds to GNU Emacs' general
                                  purpose editing features.
* Inserting::                   How to insert frequently used @-commands.
* Showing the Structure::       How to show the structure of a file.
* Updating Nodes and Menus::    How to update or create new nodes and menus.
* Info Formatting::             How to format for Info.
* Printing::                    How to format and print part or all of a file.
* Texinfo Mode Summary::        Summary of all the Texinfo mode commands.

\1f
File: texinfo.info,  Node: Texinfo Mode Overview,  Next: Emacs Editing,  Prev: Texinfo Mode,  Up: Texinfo Mode

Texinfo Mode Overview
=====================

  Texinfo mode provides special features for working with Texinfo files:

   * Insert frequently used @-commands.

   * Automatically create `@node' lines.

   * Show the structure of a Texinfo source file.

   * Automatically create or update the `Next', `Previous', and `Up'
     pointers of a node.

   * Automatically create or update menus.

   * Automatically create a master menu.

   * Format a part or all of a file for Info.

   * Typeset and print part or all of a file.

  Perhaps the two most helpful features are those for inserting
frequently used @-commands and for creating node pointers and menus.

\1f
File: texinfo.info,  Node: Emacs Editing,  Next: Inserting,  Prev: Texinfo Mode Overview,  Up: Texinfo Mode

The Usual GNU Emacs Editing Commands
====================================

In most cases, the usual Text mode commands work the same in Texinfo
mode as they do in Text mode.  Texinfo mode adds new editing commands
and tools to GNU Emacs' general purpose editing features.  The major
difference concerns filling.  In Texinfo mode, the paragraph separation
variable and syntax table are redefined so that Texinfo commands that
should be on lines of their own are not inadvertently included in
paragraphs.  Thus, the `M-q' (`fill-paragraph') command will refill a
paragraph but not mix an indexing command on a line adjacent to it into
the paragraph.

  In addition, Texinfo mode sets the `page-delimiter' variable to the
value of `texinfo-chapter-level-regexp'; by default, this is a regular
expression matching the commands for chapters and their equivalents,
such as appendices.  With this value for the page delimiter, you can
jump from chapter title to chapter title with the `C-x ]'
(`forward-page') and `C-x [' (`backward-page') commands and narrow to a
chapter with the `C-x p' (`narrow-to-page') command.  (*Note Pages:
(xemacs)Pages, for details about the page commands.)

  You may name a Texinfo file however you wish, but the convention is to
end a Texinfo file name with one of the three extensions `.texinfo',
`.texi', or `.tex'.  A longer extension is preferred, since it is
explicit, but a shorter extension may be necessary for operating
systems that limit the length of file names.  GNU Emacs automatically
enters Texinfo mode when you visit a file with a `.texinfo' or  `.texi'
extension.  Also, Emacs switches to Texinfo mode when you visit a file
that has `-*-texinfo-*-' in its first line.  If ever you are in another
mode and wish to switch to Texinfo mode, type `M-x texinfo-mode'.

  Like all other Emacs features, you can customize or enhance Texinfo
mode as you wish.  In particular, the keybindings are very easy to
change.  The keybindings described here are the default or standard
ones.

\1f
File: texinfo.info,  Node: Inserting,  Next: Showing the Structure,  Prev: Emacs Editing,  Up: Texinfo Mode

Inserting Frequently Used Commands
==================================

Texinfo mode provides commands to insert various frequently used
@-commands into the buffer.  You can use these commands to save
keystrokes.

  The insert commands are invoked by typing `C-c' twice and then the
first letter of the @-command:

`C-c C-c c'
`M-x texinfo-insert-@code'
     Insert `@code{}' and put the cursor between the braces.

`C-c C-c d'
`M-x texinfo-insert-@dfn'
     Insert `@dfn{}' and put the cursor between the braces.

`C-c C-c e'
`M-x texinfo-insert-@end'
     Insert `@end' and attempt to insert the correct following word,
     such as `example' or `table'.  (This command does not handle
     nested lists correctly, but inserts the word appropriate to the
     immediately preceding list.)

`C-c C-c i'
`M-x texinfo-insert-@item'
     Insert `@item' and put the cursor at the beginning of the next
     line.

`C-c C-c k'
`M-x texinfo-insert-@kbd'
     Insert `@kbd{}' and put the cursor between the braces.

`C-c C-c n'
`M-x texinfo-insert-@node'
     Insert `@node' and a comment line listing the sequence for the
     `Next', `Previous', and `Up' nodes.  Leave point after the `@node'.

`C-c C-c o'
`M-x texinfo-insert-@noindent'
     Insert `@noindent' and put the cursor at the beginning of the next
     line.

`C-c C-c s'
`M-x texinfo-insert-@samp'
     Insert `@samp{}' and put the cursor between the braces.

`C-c C-c t'
`M-x texinfo-insert-@table'
     Insert `@table' followed by a <SPC> and leave the cursor after the
     <SPC>.

`C-c C-c v'
`M-x texinfo-insert-@var'
     Insert `@var{}' and put the cursor between the braces.

`C-c C-c x'
`M-x texinfo-insert-@example'
     Insert `@example' and put the cursor at the beginning of the next
     line.

`C-c C-c {'
`M-x texinfo-insert-braces'
     Insert `{}' and put the cursor between the braces.

`C-c C-c }'
`C-c C-c ]'
`M-x up-list'
     Move from between a pair of braces forward past the closing brace.
     Typing `C-c C-c ]' is easier than typing `C-c C-c }', which is,
     however, more mnemonic; hence the two keybindings.  (Also, you can
     move out from between braces by typing `C-f'.)

  To put a command such as `@code{...}' around an _existing_ word,
position the cursor in front of the word and type `C-u 1 C-c C-c c'.
This makes it easy to edit existing plain text.  The value of the
prefix argument tells Emacs how many words following point to include
between braces--`1' for one word, `2' for two words, and so on.  Use a
negative argument to enclose the previous word or words.  If you do not
specify a prefix argument, Emacs inserts the @-command string and
positions the cursor between the braces.  This feature works only for
those @-commands that operate on a word or words within one line, such
as `@kbd' and `@var'.

  This set of insert commands was created after analyzing the frequency
with which different @-commands are used in the `GNU Emacs Manual' and
the `GDB Manual'.  If you wish to add your own insert commands, you can
bind a keyboard macro to a key, use abbreviations, or extend the code
in `texinfo.el'.

  `C-c C-c C-d' (`texinfo-start-menu-description') is an insert command
that works differently from the other insert commands.  It inserts a
node's section or chapter title in the space for the description in a
menu entry line.  (A menu entry has three parts, the entry name, the
node name, and the description.  Only the node name is required, but a
description helps explain what the node is about.  *Note The Parts of a
Menu: Menu Parts.)

  To use `texinfo-start-menu-description', position point in a menu
entry line and type `C-c C-c C-d'.  The command looks for and copies
the title that goes with the node name, and inserts the title as a
description; it positions point at beginning of the inserted text so you
can edit it.  The function does not insert the title if the menu entry
line already contains a description.

  This command is only an aid to writing descriptions; it does not do
the whole job.  You must edit the inserted text since a title tends to
use the same words as a node name but a useful description uses
different words.

\1f
File: texinfo.info,  Node: Showing the Structure,  Next: Updating Nodes and Menus,  Prev: Inserting,  Up: Texinfo Mode

Showing the Section Structure of a File
=======================================

You can show the section structure of a Texinfo file by using the `C-c
C-s' command (`texinfo-show-structure').  This command shows the
section structure of a Texinfo file by listing the lines that begin
with the @-commands for `@chapter', `@section', and the like.  It
constructs what amounts to a table of contents.  These lines are
displayed in another buffer called the `*Occur*' buffer.  In that
buffer, you can position the cursor over one of the lines and use the
`C-c C-c' command (`occur-mode-goto-occurrence'), to jump to the
corresponding spot in the Texinfo file.

`C-c C-s'
`M-x texinfo-show-structure'
     Show the `@chapter', `@section', and such lines of a Texinfo file.

`C-c C-c'
`M-x occur-mode-goto-occurrence'
     Go to the line in the Texinfo file corresponding to the line under
     the cursor in the `*Occur*' buffer.

  If you call `texinfo-show-structure' with a prefix argument by typing
`C-u C-c C-s', it will list not only those lines with the @-commands
for `@chapter', `@section', and the like, but also the `@node' lines.
(This is how the `texinfo-show-structure' command worked without an
argument in the first version of Texinfo.  It was changed because
`@node' lines clutter up the `*Occur*' buffer and are usually not
needed.)  You can use `texinfo-show-structure' with a prefix argument
to check whether the `Next', `Previous', and `Up' pointers of an
`@node' line are correct.

  Often, when you are working on a manual, you will be interested only
in the structure of the current chapter.  In this case, you can mark
off the region of the buffer that you are interested in by using the
`C-x n n' (`narrow-to-region') command and `texinfo-show-structure'
will work on only that region.  To see the whole buffer again, use
`C-x n w' (`widen').  (*Note Narrowing: (xemacs)Narrowing, for more
information about the narrowing commands.)

  In addition to providing the `texinfo-show-structure' command,
Texinfo mode sets the value of the page delimiter variable to match the
chapter-level @-commands.  This enables you to use the `C-x ]'
(`forward-page') and `C-x [' (`backward-page') commands to move forward
and backward by chapter, and to use the `C-x p' (`narrow-to-page')
command to narrow to a chapter.  *Note Pages: (xemacs)Pages, for more
information about the page commands.

\1f
File: texinfo.info,  Node: Updating Nodes and Menus,  Next: Info Formatting,  Prev: Showing the Structure,  Up: Texinfo Mode

Updating Nodes and Menus
========================

Texinfo mode provides commands for automatically creating or updating
menus and node pointers.  The commands are called "update" commands
because their most frequent use is for updating a Texinfo file after
you have worked on it; but you can use them to insert the `Next',
`Previous', and `Up' pointers into an `@node' line that has none and to
create menus in a file that has none.

  If you do not use the updating commands, you need to write menus and
node pointers by hand, which is a tedious task.

* Menu:

* Updating Commands::           Five major updating commands.
* Updating Requirements::       How to structure a Texinfo file for
                                  using the updating command.
* Other Updating Commands::     How to indent descriptions, insert
                                  missing nodes lines, and update
                                  nodes in sequence.

\1f
File: texinfo.info,  Node: Updating Commands,  Next: Updating Requirements,  Prev: Updating Nodes and Menus,  Up: Updating Nodes and Menus

The Updating Commands
---------------------

  You can use the updating commands

   * to insert or update the `Next', `Previous', and `Up' pointers of a
     node,

   * to insert or update the menu for a section, and

   * to create a master menu for a Texinfo source file.

  You can also use the commands to update all the nodes and menus in a
region or in a whole Texinfo file.

  The updating commands work only with conventional Texinfo files, which
are structured hierarchically like books.  In such files, a structuring
command line must follow closely after each `@node' line, except for
the `Top' `@node' line.  (A "structuring command line" is a line
beginning with `@chapter', `@section', or other similar command.)

  You can write the structuring command line on the line that follows
immediately after an `@node' line or else on the line that follows
after a single `@comment' line or a single `@ifinfo' line.  You cannot
interpose more than one line between the `@node' line and the
structuring command line; and you may interpose only an `@comment' line
or an `@ifinfo' line.

  Commands which work on a whole buffer require that the `Top' node be
followed by a node with an `@chapter' or equivalent-level command.
Note that the menu updating commands will not create a main or master
menu for a Texinfo file that has only `@chapter'-level nodes!  The menu
updating commands only create menus _within_ nodes for lower level
nodes.  To create a menu of chapters, you must provide a `Top' node.

  The menu updating commands remove menu entries that refer to other
Info files since they do not refer to nodes within the current buffer.
This is a deficiency.  Rather than use menu entries, you can use cross
references to refer to other Info files.  None of the updating commands
affect cross references.

  Texinfo mode has five updating commands that are used most often: two
are for updating the node pointers or menu of a single node (or a
region); two are for updating every node pointer and menu in a file;
and one, the `texinfo-master-menu' command, is for creating a master
menu for a complete file, and optionally, for updating every node and
menu in the whole Texinfo file.

  The `texinfo-master-menu' command is the primary command:

`C-c C-u m'
`M-x texinfo-master-menu'
     Create or update a master menu that includes all the other menus
     (incorporating the descriptions from pre-existing menus, if any).

     With an argument (prefix argument, `C-u,' if interactive), first
     create or update all the nodes and all the regular menus in the
     buffer before constructing the master menu.  (*Note The Top Node
     and Master Menu: The Top Node, for more about a master menu.)

     For `texinfo-master-menu' to work, the Texinfo file must have a
     `Top' node and at least one subsequent node.

     After extensively editing a Texinfo file, you can type the
     following:

          C-u M-x texinfo-master-menu
     or
          C-u C-c C-u m

     This updates all the nodes and menus completely and all at once.

  The other major updating commands do smaller jobs and are designed for
the person  who updates nodes and menus as he or she writes a Texinfo
file.

  The commands are:

`C-c C-u C-n'
`M-x texinfo-update-node'
     Insert the `Next', `Previous', and `Up' pointers for the node that
     point is within (i.e., for the `@node' line preceding point).  If
     the `@node' line has pre-existing `Next', `Previous', or `Up'
     pointers in it, the old pointers are removed and new ones inserted.
     With an argument (prefix argument, `C-u', if interactive), this
     command updates all `@node' lines in the region (which is the text
     between point and mark).

`C-c C-u C-m'
`M-x texinfo-make-menu'
     Create or update the menu in the node that point is within.  With
     an argument (`C-u' as prefix argument, if interactive), the
     command makes or updates menus for the nodes which are either
     within or a part of the region.

     Whenever `texinfo-make-menu' updates an existing menu, the
     descriptions from that menu are incorporated into the new menu.
     This is done by copying descriptions from the existing menu to the
     entries in the new menu that have the same node names.  If the
     node names are different, the descriptions are not copied to the
     new menu.

`C-c C-u C-e'
`M-x texinfo-every-node-update'
     Insert or update the `Next', `Previous', and `Up' pointers for
     every node in the buffer.

`C-c C-u C-a'
`M-x texinfo-all-menus-update'
     Create or update all the menus in the buffer.  With an argument
     (`C-u' as prefix argument, if interactive), first insert or update
     all the node pointers before working on the menus.

     If a master menu exists, the `texinfo-all-menus-update' command
     updates it; but the command does not create a new master menu if
     none already exists.  (Use the `texinfo-master-menu' command for
     that.)

     When working on a document that does not merit a master menu, you
     can type the following:

          C-u C-c C-u C-a
     or
          C-u M-x texinfo-all-menus-update

     This updates all the nodes and menus.

  The `texinfo-column-for-description' variable specifies the column to
which menu descriptions are indented.  By default, the value is 32
although it is often useful to reduce it to as low as 24.  You can set
the variable with the `M-x edit-options' command (*note Editing
Variable Values: (xemacs)Edit Options.) or with the `M-x set-variable'
command (*note Examining and Setting Variables: (xemacs)Examining.).

  Also, the `texinfo-indent-menu-description' command may be used to
indent existing menu descriptions to a specified column.  Finally, if
you wish, you can use the `texinfo-insert-node-lines' command to insert
missing `@node' lines into a file.  (*Note Other Updating Commands::,
for more information.)

\1f
File: texinfo.info,  Node: Updating Requirements,  Next: Other Updating Commands,  Prev: Updating Commands,  Up: Updating Nodes and Menus

Updating Requirements
---------------------

To use the updating commands, you must organize the Texinfo file
hierarchically with chapters, sections, subsections, and the like.
When you construct the hierarchy of the manual, do not `jump down' more
than one level at a time: you can follow the `Top' node with a chapter,
but not with a section; you can follow a chapter with a section, but
not with a subsection.  However, you may `jump up' any number of levels
at one time--for example, from a subsection to a chapter.

  Each `@node' line, with the exception of the line for the `Top' node,
must be followed by a line with a structuring command such as
`@chapter', `@section', or `@unnumberedsubsec'.

  Each `@node' line/structuring-command line combination must look
either like this:

     @node     Comments,  Minimum, Conventions, Overview
     @comment  node-name, next,    previous,    up
     @section Comments

  or like this (without the `@comment' line):

     @node Comments, Minimum, Conventions, Overview
     @section Comments

In this example, `Comments' is the name of both the node and the
section.  The next node is called `Minimum' and the previous node is
called `Conventions'.  The `Comments' section is within the `Overview'
node, which is specified by the `Up' pointer.  (Instead of an
`@comment' line, you can write an `@ifinfo' line.)

  If a file has a `Top' node, it must be called `top' or `Top' and be
the first node in the file.

  The menu updating commands create a menu of sections within a chapter,
a menu of subsections within a section, and so on.  This means that you
must have a `Top' node if you want a menu of chapters.

  Incidentally, the `makeinfo' command will create an Info file for a
hierarchically organized Texinfo file that lacks `Next', `Previous' and
`Up' pointers.  Thus, if you can be sure that your Texinfo file will be
formatted with `makeinfo', you have no need for the `update node'
commands.  (*Note Creating an Info File: Create an Info File, for more
information about `makeinfo'.)  However, both `makeinfo' and the
`texinfo-format-...' commands require that you insert menus in the file.

\1f
File: texinfo.info,  Node: Other Updating Commands,  Prev: Updating Requirements,  Up: Updating Nodes and Menus

Other Updating Commands
-----------------------

In addition to the five major updating commands, Texinfo mode possesses
several less frequently used updating commands:

`M-x texinfo-insert-node-lines'
     Insert `@node' lines before the `@chapter', `@section', and other
     sectioning commands wherever they are missing throughout a region
     in a Texinfo file.

     With an argument (`C-u' as prefix argument, if interactive), the
     `texinfo-insert-node-lines' command not only inserts `@node' lines
     but also inserts the chapter or section titles as the names of the
     corresponding nodes.  In addition, it inserts the titles as node
     names in pre-existing `@node' lines that lack names.  Since node
     names should be more concise than section or chapter titles, you
     must manually edit node names so inserted.

     For example, the following marks a whole buffer as a region and
     inserts `@node' lines and titles throughout:

          C-x h C-u M-x texinfo-insert-node-lines

     (Note that this command inserts titles as node names in `@node'
     lines; the `texinfo-start-menu-description' command (*note
     Inserting Frequently Used Commands: Inserting.) inserts titles as
     descriptions in menu entries, a different action.  However, in both
     cases, you need to edit the inserted text.)

`M-x texinfo-multiple-files-update'
     Update nodes and menus in a document built from several separate
     files.  With `C-u' as a prefix argument, create and insert a
     master menu in the outer file.  With a numeric prefix argument,
     such as `C-u 2', first update all the menus and all the `Next',
     `Previous', and `Up' pointers of all the included files before
     creating and inserting a master menu in the outer file.  The
     `texinfo-multiple-files-update' command is described in the
     appendix on `@include' files.  *Note
     texinfo-multiple-files-update::.

`M-x texinfo-indent-menu-description'
     Indent every description in the menu following point to the
     specified column.  You can use this command to give yourself more
     space for descriptions.  With an argument (`C-u' as prefix
     argument, if interactive), the `texinfo-indent-menu-description'
     command indents every description in every menu in the region.
     However, this command does not indent the second and subsequent
     lines of a multi-line description.

`M-x texinfo-sequential-node-update'
     Insert the names of the nodes immediately following and preceding
     the current node as the `Next' or `Previous' pointers regardless
     of those nodes' hierarchical level.  This means that the `Next'
     node of a subsection may well be the next chapter.  Sequentially
     ordered nodes are useful for novels and other documents that you
     read through sequentially.  (However, in Info, the `g *' command
     lets you look through the file sequentially, so sequentially
     ordered nodes are not strictly necessary.)  With an argument
     (prefix argument, if interactive), the
     `texinfo-sequential-node-update' command sequentially updates all
     the nodes in the region.

\1f
File: texinfo.info,  Node: Info Formatting,  Next: Printing,  Prev: Updating Nodes and Menus,  Up: Texinfo Mode

Formatting for Info
===================

Texinfo mode provides several commands for formatting part or all of a
Texinfo file for Info.  Often, when you are writing a document, you
want to format only part of a file--that is, a region.

  You can use either the `texinfo-format-region' or the
`makeinfo-region' command to format a region:

`C-c C-e C-r'
`M-x texinfo-format-region'
`C-c C-m C-r'
`M-x makeinfo-region'
     Format the current region for Info.

  You can use either the `texinfo-format-buffer' or the
`makeinfo-buffer' command to format a whole buffer:

`C-c C-e C-b'
`M-x texinfo-format-buffer'
`C-c C-m C-b'
`M-x makeinfo-buffer'
     Format the current buffer for Info.

  For example, after writing a Texinfo file, you can type the following:

     C-u C-c C-u m
or
     C-u M-x texinfo-master-menu

This updates all the nodes and menus.  Then type the following to create
an Info file:

     C-c C-m C-b
or
     M-x makeinfo-buffer

  For TeX or the Info formatting commands to work, the file _must_
include a line that has `@setfilename' in its header.

  *Note Create an Info File::, for details about Info formatting.

\1f
File: texinfo.info,  Node: Printing,  Next: Texinfo Mode Summary,  Prev: Info Formatting,  Up: Texinfo Mode

Formatting and Printing
=======================

Typesetting and printing a Texinfo file is a multi-step process in which
you first create a file for printing (called a DVI file), and then
print the file.  Optionally, you may also create indices.  To do this,
you must run the `texindex' command after first running the `tex'
typesetting command; and then you must run the `tex' command again.  Or
else run the `texi2dvi' command which automatically creates indices as
needed (*note Format with texi2dvi::).

  Often, when you are writing a document, you want to typeset and print
only part of a file to see what it will look like.  You can use the
`texinfo-tex-region' and related commands for this purpose.  Use the
`texinfo-tex-buffer' command to format all of a buffer.

`C-c C-t C-b'
`M-x texinfo-tex-buffer'
     Run `texi2dvi' on the buffer.  In addition to running TeX on the
     buffer, this command automatically creates or updates indices as
     needed.

`C-c C-t C-r'
`M-x texinfo-tex-region'
     Run TeX on the region.

`C-c C-t C-i'
`M-x texinfo-texindex'
     Run `texindex' to sort the indices of a Texinfo file formatted with
     `texinfo-tex-region'.  The `texinfo-tex-region' command does not
     run `texindex' automatically; it only runs the `tex' typesetting
     command.  You must run the `texinfo-tex-region' command a second
     time after sorting the raw index files with the `texindex'
     command.  (Usually, you do not format an index when you format a
     region, only when you format a buffer.  Now that the `texi2dvi'
     command exists, there is little or no need for this command.)

`C-c C-t C-p'
`M-x texinfo-tex-print'
     Print the file (or the part of the file) previously formatted with
     `texinfo-tex-buffer' or `texinfo-tex-region'.

  For `texinfo-tex-region' or `texinfo-tex-buffer' to work, the file
_must_ start with a `\input texinfo' line and must include an
`@settitle' line.  The file must end with `@bye' on a line by itself.
(When you use `texinfo-tex-region', you must surround the `@settitle'
line with start-of-header and end-of-header lines.)

  *Note Format/Print Hardcopy::, for a description of the other TeX
related commands, such as `tex-show-print-queue'.

\1f
File: texinfo.info,  Node: Texinfo Mode Summary,  Prev: Printing,  Up: Texinfo Mode

Texinfo Mode Summary
====================

In Texinfo mode, each set of commands has default keybindings that
begin with the same keys.  All the commands that are custom-created for
Texinfo mode begin with `C-c'.  The keys are somewhat mnemonic.

Insert Commands
---------------

The insert commands are invoked by typing `C-c' twice and then the
first letter of the @-command to be inserted.  (It might make more
sense mnemonically to use `C-c C-i', for `custom insert', but `C-c C-c'
is quick to type.)

     C-c C-c c       Insert `@code'.
     C-c C-c d       Insert `@dfn'.
     C-c C-c e       Insert `@end'.
     C-c C-c i       Insert `@item'.
     C-c C-c n       Insert `@node'.
     C-c C-c s       Insert `@samp'.
     C-c C-c v       Insert `@var'.
     C-c C-c {       Insert braces.
     C-c C-c ]
     C-c C-c }       Move out of enclosing braces.
     
     C-c C-c C-d     Insert a node's section title
                     in the space for the description
                     in a menu entry line.

Show Structure
--------------

The `texinfo-show-structure' command is often used within a narrowed
region.

     C-c C-s         List all the headings.

The Master Update Command
-------------------------

The `texinfo-master-menu' command creates a master menu; and can be
used to update every node and menu in a file as well.

     C-c C-u m
     M-x texinfo-master-menu
                     Create or update a master menu.
     
     C-u C-c C-u m   With `C-u' as a prefix argument, first
                     create or update all nodes and regular
                     menus, and then create a master menu.

Update Pointers
---------------

The update pointer commands are invoked by typing `C-c C-u' and then
either `C-n' for `texinfo-update-node' or `C-e' for
`texinfo-every-node-update'.

     C-c C-u C-n     Update a node.
     C-c C-u C-e     Update every node in the buffer.

Update Menus
------------

Invoke the  update menu commands by typing `C-c C-u' and then either
`C-m' for `texinfo-make-menu' or `C-a' for `texinfo-all-menus-update'.
To update both nodes and menus at the same time, precede `C-c C-u C-a'
with `C-u'.

     C-c C-u C-m     Make or update a menu.
     
     C-c C-u C-a     Make or update all
                     menus in a buffer.
     
     C-u C-c C-u C-a With `C-u' as a prefix argument,
                     first create or update all nodes and
                     then create or update all menus.

Format for Info
---------------

The Info formatting commands that are written in Emacs Lisp are invoked
by typing `C-c C-e' and then either `C-r' for a region or `C-b' for the
whole buffer.

  The Info formatting commands that are written in C and based on the
`makeinfo' program are invoked by typing `C-c C-m' and then either
`C-r' for a region or `C-b' for the whole buffer.

Use the `texinfo-format...' commands:

     C-c C-e C-r     Format the region.
     C-c C-e C-b     Format the buffer.

Use `makeinfo':

     C-c C-m C-r     Format the region.
     C-c C-m C-b     Format the buffer.
     C-c C-m C-l     Recenter the `makeinfo' output buffer.
     C-c C-m C-k     Kill the `makeinfo' formatting job.

Typeset and Print
-----------------

The TeX typesetting and printing commands are invoked by typing `C-c
C-t' and then another control command: `C-r' for `texinfo-tex-region',
`C-b' for `texinfo-tex-buffer', and so on.

     C-c C-t C-r     Run TeX on the region.
     C-c C-t C-b     Run `texi2dvi' on the buffer.
     C-c C-t C-i     Run `texindex'.
     C-c C-t C-p     Print the DVI file.
     C-c C-t C-q     Show the print queue.
     C-c C-t C-d     Delete a job from the print queue.
     C-c C-t C-k     Kill the current TeX formatting job.
     C-c C-t C-x     Quit a currently stopped TeX formatting job.
     C-c C-t C-l     Recenter the output buffer.

Other Updating Commands
-----------------------

The `other updating commands' do not have standard keybindings because
they are rarely used.

     M-x texinfo-insert-node-lines
                     Insert missing `@node' lines in region.
                     With `C-u' as a prefix argument,
                     use section titles as node names.
     
     M-x texinfo-multiple-files-update
                     Update a multi-file document.
                     With `C-u 2' as a prefix argument,
                     create or update all nodes and menus
                     in all included files first.
     
     M-x texinfo-indent-menu-description
                     Indent descriptions.
     
     M-x texinfo-sequential-node-update
                     Insert node pointers in strict sequence.

\1f
File: texinfo.info,  Node: Beginning a File,  Next: Ending a File,  Prev: Texinfo Mode,  Up: Top

Beginning a Texinfo File
************************

Certain pieces of information must be provided at the beginning of a
Texinfo file, such as the name of the file and the title of the
document.

* Menu:

* Four Parts::                  Four parts begin a Texinfo file.
* Sample Beginning::            Here is a sample beginning for a Texinfo file.
* Header::                      The very beginning of a Texinfo file.
* Info Summary and Permissions::  Summary and copying permissions for Info.
* Titlepage & Copyright Page::  Creating the title and copyright pages.
* The Top Node::                Creating the `Top' node and master menu.
* Software Copying Permissions::  Ensure that you and others continue to
                                  have the right to use and share software.

\1f
File: texinfo.info,  Node: Four Parts,  Next: Sample Beginning,  Prev: Beginning a File,  Up: Beginning a File

Four Parts Begin a File
=======================

  Generally, the beginning of a Texinfo file has four parts:

  1. The header, delimited by special comment lines, that includes the
     commands for naming the Texinfo file and telling TeX what
     definitions file to use when processing the Texinfo file.

  2. A short statement of what the file is about, with a copyright
     notice and copying permissions.  This is enclosed in `@ifinfo' and
     `@end ifinfo' commands so that the formatters place it only in the
     Info file.

  3. A title page and copyright page, with a copyright notice and
     copying permissions.  This is enclosed between `@titlepage' and
     `@end titlepage' commands.  The title and copyright page appear
     only in the printed manual.

  4. The `Top' node that contains a menu for the whole Info file.  The
     contents of this node appear only in the Info file.

  Also, optionally, you may include the copying conditions for a program
and a warranty disclaimer.  The copying section will be followed by an
introduction or else by the first chapter of the manual.

  Since the copyright notice and copying permissions for the Texinfo
document (in contrast to the copying permissions for a program) are in
parts that appear only in the Info file or only in the printed manual,
this information must be given twice.

\1f
File: texinfo.info,  Node: Sample Beginning,  Next: Header,  Prev: Four Parts,  Up: Beginning a File

Sample Texinfo File Beginning
=============================

The following sample shows what is needed.

     \input texinfo   @c -*-texinfo-*-
     @c %**start of header
     @setfilename NAME-OF-INFO-FILE
     @settitle NAME-OF-MANUAL
     @setchapternewpage odd
     @c %**end of header
     
     @ifinfo
     This file documents ...
     
     Copyright YEAR COPYRIGHT-OWNER
     
     Permission is granted to ...
     @end ifinfo
     
     @c  This title page illustrates only one of the
     @c  two methods of forming a title page.
     
     @titlepage
     @title NAME-OF-MANUAL-WHEN-PRINTED
     @subtitle SUBTITLE-IF-ANY
     @subtitle SECOND-SUBTITLE
     @author AUTHOR
     
     @c  The following two commands
     @c  start the copyright page.
     @page
     @vskip 0pt plus 1filll
     Copyright @copyright{} YEAR COPYRIGHT-OWNER
     
     Published by ...
     
     Permission is granted to ...
     @end titlepage
     
     @node Top, Overview, , (dir)
     
     @ifinfo
     This document describes ...
     
     This document applies to version ...
     of the program named ...
     @end ifinfo
     
     @menu
     * Copying::          Your rights and freedoms.
     * First Chapter::    Getting started ...
     * Second Chapter::              ...
       ...
       ...
     @end menu
     
     @node    First Chapter, Second Chapter, top,      top
     @comment node-name,     next,           previous, up
     @chapter First Chapter
     @cindex Index entry for First Chapter

\1f
File: texinfo.info,  Node: Header,  Next: Info Summary and Permissions,  Prev: Sample Beginning,  Up: Beginning a File

The Texinfo File Header
=======================

Texinfo files start with at least three lines that provide Info and TeX
with necessary information.  These are the `\input texinfo' line, the
`@settitle' line, and the `@setfilename' line.  If you want to run TeX
on just a part of the Texinfo File, you must write the `@settitle' and
`@setfilename' lines between start-of-header and end-of-header lines.

  Thus, the beginning of a Texinfo file looks like this:

     \input texinfo   @c -*-texinfo-*-
     @setfilename sample.info
     @settitle Sample Document

or else like this:

     \input texinfo   @c -*-texinfo-*-
     @c %**start of header
     @setfilename sample.info
     @settitle Sample Document
     @c %**end of header

* Menu:

* First Line::                  The first line of a Texinfo file.
* Start of Header::             Formatting a region requires this.
* setfilename::                 Tell Info the name of the Info file.
* settitle::                    Create a title for the printed work.
* setchapternewpage::           Start chapters on right-hand pages.
* paragraphindent::             An option to specify paragraph indentation.
* End of Header::               Formatting a region requires this.

\1f
File: texinfo.info,  Node: First Line,  Next: Start of Header,  Prev: Header,  Up: Header

The First Line of a Texinfo File
--------------------------------

Every Texinfo file that is to be the top-level input to TeX must begin
with a line that looks like this:

     \input texinfo   @c -*-texinfo-*-

This line serves two functions:

  1. When the file is processed by TeX, the `\input texinfo' command
     tells TeX to load the macros needed for processing a Texinfo file.
     These are in a file called `texinfo.tex', which is usually located
     in the `/usr/lib/tex/macros' directory.  TeX uses the backslash,
     `\', to mark the beginning of a command, just as Texinfo uses `@'.
     The `texinfo.tex' file causes the switch from `\' to `@'; before
     the switch occurs, TeX requires `\', which is why it appears at
     the beginning of the file.

  2. When the file is edited in GNU Emacs, the `-*-texinfo-*-' mode
     specification tells Emacs to use Texinfo mode.

\1f
File: texinfo.info,  Node: Start of Header,  Next: setfilename,  Prev: First Line,  Up: Header

Start of Header
---------------

Write a start-of-header line on the second line of a Texinfo file.
Follow the start-of-header line with `@setfilename' and `@settitle'
lines and, optionally, with other command lines, such as `@smallbook'
or `@footnotestyle'; and then by an end-of-header line (*note End of
Header::).

  With these lines, you can format part of a Texinfo file for Info or
typeset part for printing.

  A start-of-header line looks like this:

     @c %**start of header

  The odd string of characters, `%**', is to ensure that no other
comment is accidentally taken for a start-of-header line.

\1f
File: texinfo.info,  Node: setfilename,  Next: settitle,  Prev: Start of Header,  Up: Header

`@setfilename'
--------------

In order to serve as the primary input file for either `makeinfo' or
TeX, a Texinfo file must contain a line that looks like this:

     @setfilename INFO-FILE-NAME

  Write the `@setfilename' command at the beginning of a line and
follow it on the same line by the Info file name.  Do not write anything
else on the line; anything on the line after the command is considered
part of the file name, including what would otherwise be a comment.

  The `@setfilename' line specifies the name of the Info file to be
generated.  This name should be different from the name of the Texinfo
file.  There are two conventions for choosing the name: you can either
remove the `.texi' extension from the input file name, or replace it
with the `.info' extension.

  Some operating systems cannot handle long file names.  You can run
into a problem even when the file name you specify is itself short
enough.  This occurs because the Info formatters split a long Info file
into short indirect subfiles, and name them by appending `-1', `-2',
..., `-10', `-11', and so on, to the original file name.  (*Note Tag
Files and Split Files: Tag and Split Files.)  The subfile name
`texinfo.info-10', for example, is too long for some systems; so the
Info file name for this document is `texinfo' rather than
`texinfo.info'.

  The Info formatting commands ignore everything written before the
`@setfilename' line, which is why the very first line of the file (the
`\input' line) does not show up in the output.

  The `@setfilename' line produces no output when you typeset a manual
with TeX, but it nevertheless is essential: it opens the index,
cross-reference, and other auxiliary files used by Texinfo, and also
reads `texinfo.cnf' if that file is present on your system (*note
Preparing to Use TeX: Preparing for TeX.).

\1f
File: texinfo.info,  Node: settitle,  Next: setchapternewpage,  Prev: setfilename,  Up: Header

`@settitle'
-----------

In order to be made into a printed manual, a Texinfo file must contain
a line that looks like this:

     @settitle TITLE

  Write the `@settitle' command at the beginning of a line and follow
it on the same line by the title.  This tells TeX the title to use in a
header or footer.  Do not write anything else on the line; anything on
the line after the command is considered part of the title, including a
comment.

  Conventionally, when TeX formats a Texinfo file for double-sided
output, the title is printed in the left-hand (even-numbered) page
headings and the current chapter title is printed in the right-hand
(odd-numbered) page headings.  (TeX learns the title of each chapter
from each `@chapter' command.)  Page footers are not printed.

  Even if you are printing in a single-sided style, TeX looks for an
`@settitle' command line, in case you include the manual title in the
heading.

  The `@settitle' command should precede everything that generates
actual output in TeX.

  Although the title in the `@settitle' command is usually the same as
the title on the title page, it does not affect the title as it appears
on the title page.  Thus, the two do not need not match exactly;  and
the title in the `@settitle' command can be a shortened or expanded
version of the title as it appears on the title page. (*Note
`@titlepage': titlepage.)

  TeX prints page headings only for that text that comes after the
`@end titlepage' command in the Texinfo file, or that comes after an
`@headings' command that turns on headings.  (*Note The `@headings'
Command: headings on off, for more information.)

  You may, if you wish, create your own, customized headings and
footings.  *Note Page Headings: Headings, for a detailed discussion of
this process.

\1f
File: texinfo.info,  Node: setchapternewpage,  Next: paragraphindent,  Prev: settitle,  Up: Header

`@setchapternewpage'
--------------------

In a book or a manual, text is usually printed on both sides of the
paper, chapters start on right-hand pages, and right-hand pages have
odd numbers.  But in short reports, text often is printed only on one
side of the paper.  Also in short reports, chapters sometimes do not
start on new pages, but are printed on the same page as the end of the
preceding chapter, after a small amount of vertical whitespace.

  You can use the `@setchapternewpage' command with various arguments
to specify how TeX should start chapters and whether it should typeset
pages for printing on one or both sides of the paper (single-sided or
double-sided printing).

  Write the `@setchapternewpage' command at the beginning of a line
followed by its argument.

  For example, you would write the following to cause each chapter to
start on a fresh odd-numbered page:

     @setchapternewpage odd

  You can specify one of three alternatives with the
`@setchapternewpage' command:

`@setchapternewpage off'
     Cause TeX to typeset a new chapter on the same page as the last
     chapter, after skipping some vertical whitespace.  Also, cause TeX
     to format page headers for single-sided printing. (You can
     override the headers format with the `@headings double' command;
     see *Note The `@headings' Command: headings on off.)

`@setchapternewpage on'
     Cause TeX to start new chapters on new pages and to typeset page
     headers for single-sided printing.  This is the form most often
     used for short reports.

     This alternative is the default.

`@setchapternewpage odd'
     Cause TeX to start new chapters on new, odd-numbered pages
     (right-handed pages) and to typeset for double-sided printing.
     This is the form most often used for books and manuals.

Texinfo does not have an `@setchapternewpage even' command.

(You can countermand or modify an `@setchapternewpage' command with an
`@headings' command.  *Note The `@headings' Command: headings on off.)

  At the beginning of a manual or book, pages are not numbered--for
example, the title and copyright pages of a book are not numbered.  By
convention, table of contents pages are numbered with roman numerals
and not in sequence with the rest of the document.

  Since an Info file does not have pages, the `@setchapternewpage'
command has no effect on it.

  Usually, you do not write an `@setchapternewpage' command for
single-sided printing, but accept the default which is to typeset for
single-sided printing and to start new chapters on new pages.  Usually,
you write an `@setchapternewpage odd' command for double-sided printing.

\1f
File: texinfo.info,  Node: paragraphindent,  Next: End of Header,  Prev: setchapternewpage,  Up: Header

Paragraph Indenting
-------------------

The Info formatting commands may insert spaces at the beginning of the
first line of each paragraph, thereby indenting that paragraph.  You
can use the `@paragraphindent' command to specify the indentation.
Write an `@paragraphindent' command at the beginning of a line followed
by either `asis' or a number.  The template is:

     @paragraphindent INDENT

  The Info formatting commands indent according to the value of INDENT:

   * If the value of INDENT is `asis', the Info formatting commands do
     not change the existing indentation.

   * If the value of INDENT is zero, the Info formatting commands delete
     existing indentation.

   * If the value of INDENT is greater than zero, the Info formatting
     commands indent the paragraph by that number of spaces.

  The default value of INDENT is `asis'.

  Write the `@paragraphindent' command before or shortly after the
end-of-header line at the beginning of a Texinfo file.  (If you write
the command between the start-of-header and end-of-header lines, the
region formatting commands indent paragraphs as specified.)

  A peculiarity of the `texinfo-format-buffer' and
`texinfo-format-region' commands is that they do not indent (nor fill)
paragraphs that contain `@w' or `@*' commands.  *Note Refilling
Paragraphs::, for a detailed description of what goes on.

\1f
File: texinfo.info,  Node: End of Header,  Prev: paragraphindent,  Up: Header

End of Header
-------------

Follow the header lines with an end-of-header line.  An end-of-header
line looks like this:

     @c %**end of header

  If you include the `@setchapternewpage' command between the
start-of-header and end-of-header lines, TeX will typeset a region as
that command specifies.  Similarly, if you include an `@smallbook'
command between the start-of-header and end-of-header lines, TeX will
typeset a region in the "small" book format.

  The reason for the odd string of characters (`%**') is so that the
`texinfo-tex-region' command does not accidentally find something that
it should not when it is looking for the header.

  The start-of-header line and the end-of-header line are Texinfo mode
variables that you can change.

\1f
File: texinfo.info,  Node: Info Summary and Permissions,  Next: Titlepage & Copyright Page,  Prev: Header,  Up: Beginning a File

Summary and Copying Permissions for Info
========================================

The title page and the copyright page appear only in the printed copy of
the manual; therefore, the same information must be inserted in a
section that appears only in the Info file.  This section usually
contains a brief description of the contents of the Info file, a
copyright notice, and copying permissions.

  The copyright notice should read:

     Copyright YEAR COPYRIGHT-OWNER

and be put on a line by itself.

  Standard text for the copyright permissions is contained in an
appendix to this manual; see *Note `ifinfo' Copying Permissions: ifinfo
Permissions, for the complete text.

  The permissions text appears in an Info file _before_ the first node.
This mean that a reader does _not_ see this text when reading the file
using Info, except when using the advanced Info command `g *'.

\1f
File: texinfo.info,  Node: Titlepage & Copyright Page,  Next: The Top Node,  Prev: Info Summary and Permissions,  Up: Beginning a File

The Title and Copyright Pages
=============================

A manual's name and author are usually printed on a title page.
Sometimes copyright information is printed on the title page as well;
more often, copyright information is printed on the back of the title
page.

  The title and copyright pages appear in the printed manual, but not
in the Info file.  Because of this, it is possible to use several
slightly obscure TeX typesetting commands that cannot be used in an
Info file.  In addition, this part of the beginning of a Texinfo file
contains the text of the copying permissions that will appear in the
printed manual.

  *Note Titlepage Copying Permissions: Titlepage Permissions, for the
standard text for the copyright permissions.

* Menu:

* titlepage::                   Create a title for the printed document.
* titlefont center sp::         The `@titlefont', `@center',
                                  and `@sp' commands.
* title subtitle author::       The `@title', `@subtitle',
                                  and `@author' commands.
* Copyright & Permissions::     How to write the copyright notice and
                                  include copying permissions.
* end titlepage::               Turn on page headings after the title and
                                  copyright pages.
* headings on off::             An option for turning headings on and off
                                  and double or single sided printing.

\1f
File: texinfo.info,  Node: titlepage,  Next: titlefont center sp,  Prev: Titlepage & Copyright Page,  Up: Titlepage & Copyright Page

`@titlepage'
------------

Start the material for the title page and following copyright page with
`@titlepage' on a line by itself and end it with `@end titlepage' on a
line by itself.

  The `@end titlepage' command starts a new page and turns on page
numbering.  (*Note Page Headings: Headings, for details about how to
generate page headings.)  All the material that you want to appear on
unnumbered pages should be put between the `@titlepage' and `@end
titlepage' commands.  By using the `@page' command you can force a page
break within the region delineated by the `@titlepage' and `@end
titlepage' commands and thereby create more than one unnumbered page.
This is how the copyright page is produced.  (The `@titlepage' command
might perhaps have been better named the `@titleandadditionalpages'
command, but that would have been rather long!)

  When you write a manual about a computer program, you should write the
version of the program to which the manual applies on the title page.
If the manual changes more frequently than the program or is
independent of it, you should also include an edition number(1) (*note
titlepage-Footnote-1::) for the manual.  This helps readers keep track
of which manual is for which version of the program.  (The `Top' node
should also contain this information; see *Note `@top': makeinfo top.)

  Texinfo provides two main methods for creating a title page.  One
method uses the `@titlefont', `@sp', and `@center' commands to generate
a title page in which the words on the page are centered.

  The second method uses the `@title', `@subtitle', and `@author'
commands to create a title page with black rules under the title and
author lines and the subtitle text set flush to the right hand side of
the page.  With this method, you do not specify any of the actual
formatting of the title page.  You specify the text you want, and
Texinfo does the formatting.  You may use either method.

  For extremely simple applications, Texinfo also provides a command
`@shorttitlepage' which takes a single argument as the title.  The
argument is typeset on a page by itself and followed by a blank page.

\1f
File: texinfo.info,  Node: titlepage-Footnotes,  Up: titlepage

  (1) We have found that it is helpful to refer to versions of manuals
as `editions' and versions of programs as `versions'; otherwise, we
find we are liable to confuse each other in conversation by referring
to both the documentation and the software with the same words.

\1f
File: texinfo.info,  Node: titlefont center sp,  Next: title subtitle author,  Prev: titlepage,  Up: Titlepage & Copyright Page

`@titlefont', `@center', and `@sp'
----------------------------------

You can use the `@titlefont', `@sp', and `@center' commands to create a
title page for a printed document.  (This is the first of the two
methods for creating a title page in Texinfo.)

  Use the `@titlefont' command to select a large font suitable for the
title itself.

  For example:

     @titlefont{Texinfo}

  Use the `@center' command at the beginning of a line to center the
remaining text on that line.  Thus,

     @center @titlefont{Texinfo}

centers the title, which in this example is "Texinfo" printed in the
title font.

  Use the `@sp' command to insert vertical space.  For example:

     @sp 2

This inserts two blank lines on the printed page.  (*Note `@sp': sp,
for more information about the `@sp' command.)

  A template for this method looks like this:

     @titlepage
     @sp 10
     @center @titlefont{NAME-OF-MANUAL-WHEN-PRINTED}
     @sp 2
     @center SUBTITLE-IF-ANY
     @sp 2
     @center AUTHOR
     ...
     @end titlepage

  The spacing of the example fits an 8 1/2 by 11 inch manual.

\1f
File: texinfo.info,  Node: title subtitle author,  Next: Copyright & Permissions,  Prev: titlefont center sp,  Up: Titlepage & Copyright Page

`@title', `@subtitle', and `@author'
------------------------------------

You can use the `@title', `@subtitle', and `@author' commands to create
a title page in which the vertical and horizontal spacing is done for
you automatically.  This contrasts with the method described in the
previous section, in which the `@sp' command is needed to adjust
vertical spacing.

  Write the `@title', `@subtitle', or `@author' commands at the
beginning of a line followed by the title, subtitle, or author.

  The `@title' command produces a line in which the title is set flush
to the left-hand side of the page in a larger than normal font.  The
title is underlined with a black rule.

  The `@subtitle' command sets subtitles in a normal-sized font flush
to the right-hand side of the page.

  The `@author' command sets the names of the author or authors in a
middle-sized font flush to the left-hand side of the page on a line
near the bottom of the title page.  The names are underlined with a
black rule that is thinner than the rule that underlines the title.
(The black rule only occurs if the `@author' command line is followed
by an `@page' command line.)

  There are two ways to use the `@author' command: you can write the
name or names on the remaining part of the line that starts with an
`@author' command:

     @author by Jane Smith and John Doe

or you can write the names one above each other by using two (or more)
`@author' commands:

     @author Jane Smith
     @author John Doe

(Only the bottom name is underlined with a black rule.)

  A template for this method looks like this:

     @titlepage
     @title NAME-OF-MANUAL-WHEN-PRINTED
     @subtitle SUBTITLE-IF-ANY
     @subtitle SECOND-SUBTITLE
     @author AUTHOR
     @page
     ...
     @end titlepage

Contrast this form with the form of a title page written using the
`@sp', `@center', and `@titlefont' commands:

     @titlepage
     @sp 10
     @center @titlefont{Name of Manual When Printed}
     @sp 2
     @center Subtitle, If Any
     @sp 1
     @center Second subtitle
     @sp 2
     @center Author
     @page
     ...
     @end titlepage

\1f
File: texinfo.info,  Node: Copyright & Permissions,  Next: end titlepage,  Prev: title subtitle author,  Up: Titlepage & Copyright Page

Copyright Page and Permissions
------------------------------

By international treaty, the copyright notice for a book should be
either on the title page or on the back of the title page.  The
copyright notice should include the year followed by the name of the
organization or person who owns the copyright.

  When the copyright notice is on the back of the title page, that page
is customarily not numbered.  Therefore, in Texinfo, the information on
the copyright page should be within `@titlepage' and `@end titlepage'
commands.

  Use the `@page' command to cause a page break.  To push the copyright
notice and the other text on the copyright page towards the bottom of
the page, you can write a somewhat mysterious line after the `@page'
command that reads like this:

     @vskip 0pt plus 1filll

This is a TeX command that is not supported by the Info formatting
commands.  The `@vskip' command inserts whitespace.  The `0pt plus
1filll' means to put in zero points of mandatory whitespace, and as
much optional whitespace as needed to push the following text to the
bottom of the page.  Note the use of three `l's in the word `filll';
this is the correct usage in TeX.

  In a printed manual, the `@copyright{}' command generates a `c'
inside a circle.  (In Info, it generates `(C)'.)  The copyright notice
itself has the following legally defined sequence:

     Copyright (C) YEAR COPYRIGHT-OWNER

  It is customary to put information on how to get a manual after the
copyright notice, followed by the copying permissions for the manual.

  Note that permissions must be given here as well as in the summary
segment within `@ifinfo' and `@end ifinfo' that immediately follows the
header since this text appears only in the printed manual and the
`ifinfo' text appears only in the Info file.

  *Note Sample Permissions::, for the standard text.

\1f
File: texinfo.info,  Node: end titlepage,  Next: headings on off,  Prev: Copyright & Permissions,  Up: Titlepage & Copyright Page

Heading Generation
------------------

An `@end titlepage' command on a line by itself not only marks the end
of the title and copyright pages, but also causes TeX to start
generating page headings and page numbers.

  To repeat what is said elsewhere,  Texinfo has two standard page
heading formats, one for documents which are printed on one side of
each sheet of paper (single-sided printing), and the other for
documents which are printed on both sides of each sheet (double-sided
printing).  (*Note `@setchapternewpage': setchapternewpage.)  You can
specify these formats in different ways:

   * The conventional way is to write an `@setchapternewpage' command
     before the title page commands, and then have the `@end titlepage'
     command start generating page headings in the manner desired.
     (*Note `@setchapternewpage': setchapternewpage.)

   * Alternatively, you can use the `@headings' command to prevent page
     headings from being generated or to start them for either single or
     double-sided printing.  (Write an `@headings' command immediately
     after the `@end titlepage' command.  *Note The `@headings'
     Command: headings on off, for more information.)

   * Or, you may specify your own page heading and footing format.
     *Note Page Headings: Headings, for detailed information about page
     headings and footings.

  Most documents are formatted with the standard single-sided or
double-sided format, using `@setchapternewpage odd' for double-sided
printing and no `@setchapternewpage' command for single-sided printing.

\1f
File: texinfo.info,  Node: headings on off,  Prev: end titlepage,  Up: Titlepage & Copyright Page

The `@headings' Command
-----------------------

The `@headings' command is rarely used.  It specifies what kind of page
headings and footings to print on each page.  Usually, this is
controlled by the `@setchapternewpage' command.  You need the
`@headings' command only if the `@setchapternewpage' command does not
do what you want, or if you want to turn off pre-defined page headings
prior to defining your own.  Write an `@headings' command immediately
after the `@end titlepage' command.

  You can use `@headings' as follows:

`@headings off'
     Turn off printing of page headings.

`@headings single'
     Turn on page headings appropriate for single-sided printing.

`@headings double'
     Turn on page headings appropriate for double-sided printing.  The
     two commands, `@headings on' and `@headings double', are
     synonymous.

`@headings singleafter'
`@headings doubleafter'
     Turn on `single' or `double' headings, respectively, after the
     current page is output.

`@headings on'
     Turn on page headings: `single' if `@setchapternewpage on',
     `double' otherwise.

  For example, suppose you write `@setchapternewpage off' before the
`@titlepage' command to tell TeX to start a new chapter on the same
page as the end of the last chapter.  This command also causes TeX to
typeset page headers for single-sided printing.  To cause TeX to
typeset for double sided printing, write `@headings double' after the
`@end titlepage' command.

  You can stop TeX from generating any page headings at all by writing
`@headings off' on a line of its own immediately after the line
containing the `@end titlepage' command, like this:

     @end titlepage
     @headings off

The `@headings off' command overrides the `@end titlepage' command,
which would otherwise cause TeX to print page headings.

  You can also specify your own style of page heading and footing.
*Note Page Headings: Headings, for more information.

\1f
File: texinfo.info,  Node: The Top Node,  Next: Software Copying Permissions,  Prev: Titlepage & Copyright Page,  Up: Beginning a File

The `Top' Node and Master Menu
==============================

The `Top' node is the node from which you enter an Info file.

  A `Top' node should contain a brief description of the Info file and
an extensive, master menu for the whole Info file.  This helps the
reader understand what the Info file is about.  Also, you should write
the version number of the program to which the Info file applies; or,
at least, the edition number.

  The contents of the `Top' node should appear only in the Info file;
none of it should appear in printed output, so enclose it between
`@ifinfo' and `@end ifinfo' commands.  (TeX does not print either an
`@node' line or a menu; they appear only in Info; strictly speaking,
you are not required to enclose these parts between `@ifinfo' and `@end
ifinfo', but it is simplest to do so.  *Note Conditionally Visible
Text: Conditionals.)

* Menu:

* Title of Top Node::           Sketch what the file is about.
* Master Menu Parts::           A master menu has three or more parts.

\1f
File: texinfo.info,  Node: Title of Top Node,  Next: Master Menu Parts,  Prev: The Top Node,  Up: The Top Node

`Top' Node Title
----------------

  Sometimes, you will want to place an `@top' sectioning command line
containing the title of the document immediately after the `@node Top'
line (*note The `@top' Sectioning Command: makeinfo top command., for
more information).

  For example, the beginning of the Top node of this manual contains an
`@top' sectioning command, a short description, and edition and version
information.  It looks like this:

     ...
     @end titlepage
     
     @ifinfo
     @node Top, Copying, , (dir)
     @top Texinfo
     
     Texinfo is a documentation system...
     
     This is edition...
     ...
     @end ifinfo
     
     @menu
     * Copying::                 Texinfo is freely
                                   redistributable.
     * Overview::                What is Texinfo?
     ...
     @end menu

  In a `Top' node, the `Previous', and `Up' nodes usually refer to the
top level directory of the whole Info system, which is called `(dir)'.
The `Next' node refers to the first node that follows the main or master
menu, which is usually the copying permissions, introduction, or first
chapter.

\1f
File: texinfo.info,  Node: Master Menu Parts,  Prev: Title of Top Node,  Up: The Top Node

Parts of a Master Menu
----------------------

A "master menu" is a detailed main menu listing all the nodes in a file.

  A master menu is enclosed in `@menu' and `@end menu' commands and
does not appear in the printed document.

  Generally, a master menu is divided into parts.

   * The first part contains the major nodes in the Texinfo file: the
     nodes for the chapters, chapter-like sections, and the appendices.

   * The second part contains nodes for the indices.

   * The third and subsequent parts contain a listing of the other,
     lower level nodes, often ordered by chapter.  This way, rather
     than go through an intermediary menu, an inquirer can go directly
     to a particular node when searching for specific information.
     These menu items are not required; add them if you think they are a
     convenience.  If you do use them, put `@detailmenu' before the
     first one, and `@end detailmenu' after the last; otherwise,
     `makeinfo' will get confused.

  Each section in the menu can be introduced by a descriptive line.  So
long as the line does not begin with an asterisk, it will not be
treated as a menu entry.  (*Note Writing a Menu::, for more
information.)

  For example, the master menu for this manual looks like the following
(but has many more entries):

     @menu
     * Copying::             Texinfo is freely
                               redistributable.
     * Overview::            What is Texinfo?
     * Texinfo Mode::        Special features in GNU Emacs.
     ...
     ...
     * Command and Variable Index::
                             An entry for each @-command.
     * Concept Index::       An entry for each concept.
     
     @detailmenu
      --- The Detailed Node Listing ---
     
     Overview of Texinfo
     
     * Info Files::          What is an Info file?
     * Printed Manuals::     Characteristics of
                               a printed manual.
     ...
     ...
     
     Using Texinfo Mode
     
     * Info on a Region::    Formatting part of a file
                               for Info.
     ...
     ...
     @end detailmenu
     @end menu

\1f
File: texinfo.info,  Node: Software Copying Permissions,  Prev: The Top Node,  Up: Beginning a File

Software Copying Permissions
============================

If the Texinfo file has a section containing the "General Public
License" and the distribution information and a warranty disclaimer for
the software that is documented, this section usually follows the `Top'
node.  The General Public License is very important to Project GNU
software.  It ensures that you and others will continue to have a right
to use and share the software.

  The copying and distribution information and the disclaimer are
followed by an introduction or else by the first chapter of the manual.

  Although an introduction is not a required part of a Texinfo file, it
is very helpful.  Ideally, it should state clearly and concisely what
the file is about and who would be interested in reading it.  In
general, an introduction would follow the licensing and distribution
information, although sometimes people put it earlier in the document.
Usually, an introduction is put in an `@unnumbered' section.  (*Note
The `@unnumbered' and `@appendix' Commands: unnumbered & appendix.)

\1f
File: texinfo.info,  Node: Ending a File,  Next: Structuring,  Prev: Beginning a File,  Up: Top

Ending a Texinfo File
*********************

The end of a Texinfo file should include the commands that create
indices and generate detailed and summary tables of contents.  And it
must include the `@bye' command that marks the last line processed by
TeX.

  For example:

     @node    Concept Index,     , Variables Index, Top
     @c        node-name,    next, previous,        up
     @unnumbered Concept Index
     
     @printindex cp
     
     @contents
     @bye

* Menu:

* Printing Indices & Menus::    How to print an index in hardcopy and
                                  generate index menus in Info.
* Contents::                    How to create a table of contents.
* File End::                    How to mark the end of a file.

\1f
File: texinfo.info,  Node: Printing Indices & Menus,  Next: Contents,  Prev: Ending a File,  Up: Ending a File

Index Menus and Printing an Index
=================================

To print an index means to include it as part of a manual or Info file.
This does not happen automatically just because you use `@cindex' or
other index-entry generating commands in the Texinfo file; those just
cause the raw data for the index to be accumulated.  To generate an
index, you must include the `@printindex' command at the place in the
document where you want the index to appear.  Also, as part of the
process of creating a printed manual, you must run a program called
`texindex' (*note Format/Print Hardcopy::) to sort the raw data to
produce a sorted index file.  The sorted index file is what is actually
used to print the index.

  Texinfo offers six different types of predefined index: the concept
index, the function index, the variables index, the keystroke index, the
program index, and the data type index (*note Predefined Indices::).
Each index type has a two-letter name: `cp', `fn', `vr', `ky', `pg',
and `tp'.  You may merge indices, or put them into separate sections
(*note Combining Indices::); or you may define your own indices (*note
Defining New Indices: New Indices.).

  The `@printindex' command takes a two-letter index name, reads the
corresponding sorted index file and formats it appropriately into an
index.

  The `@printindex' command does not generate a chapter heading for the
index.  Consequently, you should precede the `@printindex' command with
a suitable section or chapter command (usually `@unnumbered') to supply
the chapter heading and put the index into the table of contents.
Precede the `@unnumbered' command with an `@node' line.

  For example:

     @node Variable Index, Concept Index, Function Index, Top
     @comment    node-name,         next,       previous, up
     @unnumbered Variable Index
     
     @printindex vr
     
     @node     Concept Index,     , Variable Index, Top
     @comment      node-name, next,       previous, up
     @unnumbered Concept Index
     
     @printindex cp
     
     @summarycontents
     @contents
     @bye

(Readers often prefer that the concept index come last in a book, since
that makes it easiest to find.)

\1f
File: texinfo.info,  Node: Contents,  Next: File End,  Prev: Printing Indices & Menus,  Up: Ending a File

Generating a Table of Contents
==============================

The `@chapter', `@section', and other structuring commands supply the
information to make up a table of contents, but they do not cause an
actual table to appear in the manual.  To do this, you must use the
`@contents' and `@summarycontents' commands:

`@contents'
     Generate a table of contents in a printed manual, including all
     chapters, sections, subsections, etc., as well as appendices and
     unnumbered chapters.  (Headings generated by the `@heading' series
     of commands do not appear in the table of contents.)  The
     `@contents' command should be written on a line by itself.

`@shortcontents'
`@summarycontents'
     (`@summarycontents' is a synonym for `@shortcontents'; the two
     commands are exactly the same.)

     Generate a short or summary table of contents that lists only the
     chapters (and appendices and unnumbered chapters).  Omit sections,
     subsections and subsubsections.  Only a long manual needs a short
     table of contents in addition to the full table of contents.

     Write the `@shortcontents' command on a line by itself right
     _before_ the `@contents' command.

  The table of contents commands automatically generate a chapter-like
heading at the top of the first table of contents page.  Write the table
of contents commands at the very end of a Texinfo file, just before the
`@bye' command, following any index sections--anything in the Texinfo
file after the table of contents commands will be omitted from the
table of contents.

  When you print a manual with a table of contents, the table of
contents are printed last and numbered with roman numerals.  You need
to place those pages in their proper place, after the title page,
yourself.  (This is the only collating you need to do for a printed
manual.  The table of contents is printed last because it is generated
after the rest of the manual is typeset.)

  Here is an example of where to write table of contents commands:

     INDICES...
     @shortcontents
     @contents
     @bye

  Since an Info file uses menus instead of tables of contents, the Info
formatting commands ignore the `@contents' and `@shortcontents'
commands.

\1f
File: texinfo.info,  Node: File End,  Prev: Contents,  Up: Ending a File

`@bye' File Ending
==================

An `@bye' command terminates TeX or Info formatting.  None of the
formatting commands see any of the file following `@bye'.  The `@bye'
command should be on a line by itself.

  If you wish, you may follow the `@bye' line with notes. These notes
will not be formatted and will not appear in either Info or a printed
manual; it is as if text after `@bye' were within `@ignore' ... `@end
ignore'.  Also, you may follow the `@bye' line with a local variables
list.  *Note Using Local Variables and the Compile Command:
Compile-Command, for more information.

\1f
File: texinfo.info,  Node: Structuring,  Next: Nodes,  Prev: Ending a File,  Up: Top

Chapter Structuring
*******************

The "chapter structuring" commands divide a document into a hierarchy of
chapters, sections, subsections, and subsubsections.  These commands
generate large headings; they also provide information for the table of
contents of a printed manual (*note Generating a Table of Contents:
Contents.).

  The chapter structuring commands do not create an Info node structure,
so normally you should put an `@node' command immediately before each
chapter structuring command (*note Nodes::).  The only time you are
likely to use the chapter structuring commands without using the node
structuring commands is if you are writing a document that contains no
cross references and will never be transformed into Info format.

  It is unlikely that you will ever write a Texinfo file that is
intended only as an Info file and not as a printable document.  If you
do, you might still use chapter structuring commands to create a
heading at the top of each node--but you don't need to.

* Menu:

* Tree Structuring::            A manual is like an upside down tree ...
* Structuring Command Types::   How to divide a manual into parts.
* makeinfo top::                The `@top' command, part of the `Top' node.
* chapter::
* unnumbered & appendix::
* majorheading & chapheading::
* section::
* unnumberedsec appendixsec heading::
* subsection::
* unnumberedsubsec appendixsubsec subheading::
* subsubsection::               Commands for the lowest level sections.
* Raise/lower sections::        How to change commands' hierarchical level.

\1f
File: texinfo.info,  Node: Tree Structuring,  Next: Structuring Command Types,  Prev: Structuring,  Up: Structuring

Tree Structure of Sections
==========================

A Texinfo file is usually structured like a book with chapters,
sections, subsections, and the like.  This structure can be visualized
as a tree (or rather as an upside-down tree) with the root at the top
and the levels corresponding to chapters, sections, subsection, and
subsubsections.

  Here is a diagram that shows a Texinfo file with three chapters, each
of which has two sections.

                               Top
                                |
              -------------------------------------
             |                  |                  |
          Chapter 1          Chapter 2          Chapter 3
             |                  |                  |
          --------           --------           --------
         |        |         |        |         |        |
      Section  Section   Section  Section   Section  Section
        1.1      1.2       2.1      2.2       3.1      3.2

  In a Texinfo file that has this structure, the beginning of Chapter 2
looks like this:

     @node    Chapter 2,  Chapter 3, Chapter 1, top
     @chapter Chapter 2

  The chapter structuring commands are described in the sections that
follow; the `@node' and `@menu' commands are described in following
chapters. (*Note Nodes::, and see *Note Menus::.)

\1f
File: texinfo.info,  Node: Structuring Command Types,  Next: makeinfo top,  Prev: Tree Structuring,  Up: Structuring

Types of Structuring Commands
=============================

The chapter structuring commands fall into four groups or series, each
of which contains structuring commands corresponding to the
hierarchical levels of chapters, sections, subsections, and
subsubsections.

  The four groups are the `@chapter' series, the `@unnumbered' series,
the `@appendix' series, and the `@heading' series.

  Each command produces titles that have a different appearance on the
printed page or Info file; only some of the commands produce titles
that are listed in the table of contents of a printed book or manual.

   * The `@chapter' and `@appendix' series of commands produce numbered
     or lettered entries both in the body of a printed work and in its
     table of contents.

   * The `@unnumbered' series of commands produce unnumbered entries
     both in the body of a printed work and in its table of contents.
     The `@top' command, which has a special use, is a member of this
     series (*note `@top': makeinfo top.).

   * The `@heading' series of commands produce unnumbered headings that
     do not appear in a table of contents.  The heading commands never
     start a new page.

   * The `@majorheading' command produces results similar to using the
     `@chapheading' command but generates a larger vertical whitespace
     before the heading.

   * When an `@setchapternewpage' command says to do so, the
     `@chapter', `@unnumbered', and `@appendix' commands start new
     pages in the printed manual; the `@heading' commands do not.

  Here are the four groups of chapter structuring commands:


                                                            No new pages
     Numbered       Unnumbered       Lettered and numbered  Unnumbered
     In contents    In contents          In contents        Not in contents
     
                    @top                                    @majorheading
     @chapter       @unnumbered          @appendix          @chapheading
     @section       @unnumberedsec       @appendixsec       @heading
     @subsection    @unnumberedsubsec    @appendixsubsec    @subheading
     @subsubsection @unnumberedsubsubsec @appendixsubsubsec @subsubheading

\1f
File: texinfo.info,  Node: makeinfo top,  Next: chapter,  Prev: Structuring Command Types,  Up: Structuring

`@top'
======

The `@top' command is a special sectioning command that you use only
after an `@node Top' line at the beginning of a Texinfo file.  The
`@top' command tells the `makeinfo' formatter which node is the `Top'
node.  It has the same typesetting effect as `@unnumbered' (*note
`@unnumbered': (`@appendix')unnumbered & appendix.).  For detailed
information, see *Note The `@top' Command: makeinfo top command.

\1f
File: texinfo.info,  Node: chapter,  Next: unnumbered & appendix,  Prev: makeinfo top,  Up: Structuring

`@chapter'
==========

`@chapter' identifies a chapter in the document.  Write the command at
the beginning of a line and follow it on the same line by the title of
the chapter.

  For example, this chapter in this manual is entitled "Chapter
Structuring"; the `@chapter' line looks like this:

     @chapter Chapter Structuring

  In TeX, the `@chapter' command creates a chapter in the document,
specifying the chapter title.  The chapter is numbered automatically.

  In Info, the `@chapter' command causes the title to appear on a line
by itself, with a line of asterisks inserted underneath.  Thus, in
Info, the above example produces the following output:

     Chapter Structuring
     *******************

  Texinfo also provides a command `@centerchap', which is analogous to
`@unnumbered', but centers its argument in the printed output.  This
kind of stylistic choice is not usually offered by Texinfo.

\1f
File: texinfo.info,  Node: unnumbered & appendix,  Next: majorheading & chapheading,  Prev: chapter,  Up: Structuring

`@unnumbered', `@appendix'
==========================

Use the `@unnumbered' command to create a chapter that appears in a
printed manual without chapter numbers of any kind.  Use the
`@appendix' command to create an appendix in a printed manual that is
labelled by letter instead of by number.

  For Info file output, the `@unnumbered' and `@appendix' commands are
equivalent to `@chapter': the title is printed on a line by itself with
a line of asterisks underneath.  (*Note `@chapter': chapter.)

  To create an appendix or an unnumbered chapter, write an `@appendix'
or `@unnumbered' command at the beginning of a line and follow it on
the same line by the title, as you would if you were creating a chapter.

\1f
File: texinfo.info,  Node: majorheading & chapheading,  Next: section,  Prev: unnumbered & appendix,  Up: Structuring

`@majorheading', `@chapheading'
===============================

The `@majorheading' and `@chapheading' commands put chapter-like
headings in the body of a document.

  However, neither command causes TeX to produce a numbered heading or
an entry in the table of contents; and neither command causes TeX to
start a new page in a printed manual.

  In TeX, an `@majorheading' command generates a larger vertical
whitespace before the heading than an `@chapheading' command but is
otherwise the same.

  In Info, the `@majorheading' and `@chapheading' commands are
equivalent to `@chapter': the title is printed on a line by itself with
a line of asterisks underneath.  (*Note `@chapter': chapter.)

\1f
File: texinfo.info,  Node: section,  Next: unnumberedsec appendixsec heading,  Prev: majorheading & chapheading,  Up: Structuring

`@section'
==========

In a printed manual, an `@section' command identifies a numbered
section within a chapter.  The section title appears in the table of
contents.  In Info, an `@section' command provides a title for a
segment of text, underlined with `='.

  This section is headed with an `@section' command and looks like this
in the Texinfo file:

     @section @code{@@section}

  To create a section, write the `@section' command at the beginning of
a line and follow it on the same line by the section title.

  Thus,

     @section This is a section

produces

     This is a section
     =================

in Info.

\1f
File: texinfo.info,  Node: unnumberedsec appendixsec heading,  Next: subsection,  Prev: section,  Up: Structuring

`@unnumberedsec', `@appendixsec', `@heading'
============================================

The `@unnumberedsec', `@appendixsec', and `@heading' commands are,
respectively, the unnumbered, appendix-like, and heading-like
equivalents of the `@section' command.  (*Note `@section': section.)

`@unnumberedsec'
     The `@unnumberedsec' command may be used within an unnumbered
     chapter or within a regular chapter or appendix to provide an
     unnumbered section.

`@appendixsec'
`@appendixsection'
     `@appendixsection' is a longer spelling of the `@appendixsec'
     command; the two are synonymous.

     Conventionally, the `@appendixsec' or `@appendixsection' command
     is used only within appendices.

`@heading'
     You may use the `@heading' command anywhere you wish for a
     section-style heading that will not appear in the table of
     contents.

\1f
File: texinfo.info,  Node: subsection,  Next: unnumberedsubsec appendixsubsec subheading,  Prev: unnumberedsec appendixsec heading,  Up: Structuring

The `@subsection' Command
=========================

Subsections are to sections as sections are to chapters.  (*Note
`@section': section.)  In Info, subsection titles are underlined with
`-'.  For example,

     @subsection This is a subsection

produces

     This is a subsection
     --------------------

  In a printed manual, subsections are listed in the table of contents
and are numbered three levels deep.

\1f
File: texinfo.info,  Node: unnumberedsubsec appendixsubsec subheading,  Next: subsubsection,  Prev: subsection,  Up: Structuring

The `@subsection'-like Commands
===============================

The `@unnumberedsubsec', `@appendixsubsec', and `@subheading' commands
are, respectively, the unnumbered, appendix-like, and heading-like
equivalents of the `@subsection' command.  (*Note `@subsection':
subsection.)

  In Info, the `@subsection'-like commands generate a title underlined
with hyphens.  In a printed manual, an `@subheading' command produces a
heading like that of a subsection except that it is not numbered and
does not appear in the table of contents.  Similarly, an
`@unnumberedsubsec' command produces an unnumbered heading like that of
a subsection and an `@appendixsubsec' command produces a
subsection-like heading labelled with a letter and numbers; both of
these commands produce headings that appear in the table of contents.

\1f
File: texinfo.info,  Node: subsubsection,  Next: Raise/lower sections,  Prev: unnumberedsubsec appendixsubsec subheading,  Up: Structuring

The `subsub' Commands
=====================

The fourth and lowest level sectioning commands in Texinfo are the
`subsub' commands.  They are:

`@subsubsection'
     Subsubsections are to subsections as subsections are to sections.
     (*Note `@subsection': subsection.)  In a printed manual,
     subsubsection titles appear in the table of contents and are
     numbered four levels deep.

`@unnumberedsubsubsec'
     Unnumbered subsubsection titles appear in the table of contents of
     a printed manual, but lack numbers.  Otherwise, unnumbered
     subsubsections are the same as subsubsections.  In Info, unnumbered
     subsubsections look exactly like ordinary subsubsections.

`@appendixsubsubsec'
     Conventionally, appendix commands are used only for appendices and
     are lettered and numbered appropriately in a printed manual.  They
     also appear in the table of contents.  In Info, appendix
     subsubsections look exactly like ordinary subsubsections.

`@subsubheading'
     The `@subsubheading' command may be used anywhere that you need a
     small heading that will not appear in the table of contents.  In
     Info, subsubheadings look exactly like ordinary subsubsection
     headings.

  In Info,  `subsub' titles are underlined with periods.  For example,

     @subsubsection This is a subsubsection

produces

     This is a subsubsection
     .......................

\1f
File: texinfo.info,  Node: Raise/lower sections,  Prev: subsubsection,  Up: Structuring

`@raisesections' and `@lowersections'
=====================================

The `@raisesections' and `@lowersections' commands raise and lower the
hierarchical level of chapters, sections, subsections and the like.
The `@raisesections' command changes sections to chapters, subsections
to sections, and so on.  The `@lowersections' command changes chapters
to sections, sections to subsections, and so on.

  An `@lowersections' command is useful if you wish to include text
that is written as an outer or standalone Texinfo file in another
Texinfo file as an inner, included file.  If you write the command at
the beginning of the file, all your `@chapter' commands are formatted
as if they were `@section' commands, all your `@section' command are
formatted as if they were `@subsection' commands, and so on.

  `@raisesections' raises a command one level in the chapter
structuring hierarchy:

       Change           To
     
     @subsection     @section,
     @section        @chapter,
     @heading        @chapheading,
               etc.

  `@lowersections' lowers a command one level in the chapter
structuring hierarchy:

       Change           To
     
     @chapter        @section,
     @subsection     @subsubsection,
     @heading        @subheading,
               etc.

  An `@raisesections' or `@lowersections' command changes only those
structuring commands that follow the command in the Texinfo file.
Write an `@raisesections' or `@lowersections' command on a line of its
own.

  An `@lowersections' command cancels an `@raisesections' command, and
vice versa.  Typically, the commands are used like this:

     @lowersections
     @include somefile.texi
     @raisesections

  Without the `@raisesections', all the subsequent sections in your
document will be lowered.

  Repeated use of the commands continue to raise or lower the
hierarchical level a step at a time.

  An attempt to raise above `chapters' reproduces chapter commands; an
attempt to lower below `subsubsections' reproduces subsubsection
commands.

\1f
File: texinfo.info,  Node: Nodes,  Next: Menus,  Prev: Structuring,  Up: Top

Nodes
*****

"Nodes" are the primary segments of a Texinfo file.  They do not
themselves impose a hierarchic or any other kind of structure on a file.
Nodes contain "node pointers" that name other nodes, and can contain
"menus" which are lists of nodes.  In Info, the movement commands can
carry you to a pointed-to node or to a node listed in a menu.  Node
pointers and menus provide structure for Info files just as chapters,
sections, subsections, and the like, provide structure for printed
books.

* Menu:

* Two Paths::                   Different commands to structure
                                  Info output and printed output.
* Node Menu Illustration::      A diagram, and sample nodes and menus.
* node::                        How to write a node, in detail.
* makeinfo Pointer Creation::   How to create node pointers with `makeinfo'.

\1f
File: texinfo.info,  Node: Two Paths,  Next: Node Menu Illustration,  Prev: Nodes,  Up: Nodes

Two Paths
=========

  The node and menu commands and the chapter structuring commands are
independent of each other:

   * In Info, node and menu commands provide structure.  The chapter
     structuring commands generate headings with different kinds of
     underlining--asterisks for chapters, hyphens for sections, and so
     on; they do nothing else.

   * In TeX, the chapter structuring commands generate chapter and
     section numbers and tables of contents.  The node and menu
     commands provide information for cross references; they do nothing
     else.

  You can use node pointers and menus to structure an Info file any way
you want; and you can write a Texinfo file so that its Info output has a
different structure than its printed output.  However, most Texinfo
files are written such that the structure for the Info output
corresponds to the structure for the printed output.  It is not
convenient to do otherwise.

  Generally, printed output is structured in a tree-like hierarchy in
which the chapters are the major limbs from which the sections branch
out.  Similarly, node pointers and menus are organized to create a
matching structure in the Info output.

\1f
File: texinfo.info,  Node: Node Menu Illustration,  Next: node,  Prev: Two Paths,  Up: Nodes

Node and Menu Illustration
==========================

Here is a copy of the diagram shown earlier that illustrates a Texinfo
file with three chapters, each of which contains two sections.

  Note that the "root" is at the top of the diagram and the "leaves"
are at the bottom.  This is how such a diagram is drawn conventionally;
it illustrates an upside-down tree.  For this reason, the root node is
called the `Top' node, and `Up' node pointers carry you closer to the
root.

                               Top
                                |
              -------------------------------------
             |                  |                  |
          Chapter 1          Chapter 2          Chapter 3
             |                  |                  |
          --------           --------           --------
         |        |         |        |         |        |
      Section  Section   Section  Section   Section  Section
        1.1      1.2       2.1      2.2       3.1      3.2

  Write the beginning of the node for Chapter 2 like this:

     @node     Chapter 2,  Chapter 3, Chapter 1, top
     @comment  node-name,  next,      previous,  up

This `@node' line says that the name of this node is "Chapter 2", the
name of the `Next' node is "Chapter 3", the name of the `Previous' node
is "Chapter 1", and the name of the `Up' node is "Top".

     *Please Note:* `Next' refers to the next node at the same
     hierarchical level in the manual, not necessarily to the next node
     within the Texinfo file.  In the Texinfo file, the subsequent node
     may be at a lower level--a section-level node may follow a
     chapter-level node, and a subsection-level node may follow a
     section-level node.  `Next' and `Previous' refer to nodes at the
     _same_ hierarchical level.  (The `Top' node contains the exception
     to this rule.  Since the `Top' node is the only node at that
     level, `Next' refers to the first following node, which is almost
     always a chapter or chapter-level node.)

  To go to Sections 2.1 and 2.2 using Info, you need a menu inside
Chapter 2.  (*Note Menus::.)  You would write the menu just before the
beginning of Section 2.1, like this:

         @menu
         * Sect. 2.1::    Description of this section.
         * Sect. 2.2::
         @end menu

  Write the node for Sect. 2.1 like this:

         @node     Sect. 2.1, Sect. 2.2, Chapter 2, Chapter 2
         @comment  node-name, next,      previous,  up

  In Info format, the `Next' and `Previous' pointers of a node usually
lead to other nodes at the same level--from chapter to chapter or from
section to section (sometimes, as shown, the `Previous' pointer points
up); an `Up' pointer usually leads to a node at the level above (closer
to the `Top' node); and a `Menu' leads to nodes at a level below (closer
to `leaves').  (A cross reference can point to a node at any level; see
*Note Cross References::.)

  Usually, an `@node' command and a chapter structuring command are
used in sequence, along with indexing commands.  (You may follow the
`@node' line with a comment line that reminds you which pointer is
which.)

  Here is the beginning of the chapter in this manual called "Ending a
Texinfo File".  This shows an `@node' line followed by a comment line,
an `@chapter' line, and then by indexing lines.

     @node    Ending a File, Structuring, Beginning a File, Top
     @comment node-name,     next,        previous,         up
     @chapter Ending a Texinfo File
     @cindex Ending a Texinfo file
     @cindex Texinfo file ending
     @cindex File ending

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File: texinfo.info,  Node: node,  Next: makeinfo Pointer Creation,  Prev: Node Menu Illustration,  Up: Nodes

The `@node' Command
===================

A "node" is a segment of text that begins at an `@node' command and
continues until the next `@node' command.  The definition of node is
different from that for chapter or section.  A chapter may contain
sections and a section may contain subsections; but a node cannot
contain subnodes; the text of a node continues only until the next
`@node' command in the file.  A node usually contains only one chapter
structuring command, the one that follows the `@node' line.  On the
other hand, in printed output nodes are used only for cross references,
so a chapter or section may contain any number of nodes.  Indeed, a
chapter usually contains several nodes, one for each section,
subsection, and subsubsection.

  To create a node, write an `@node' command at the beginning of a
line, and follow it with four arguments, separated by commas, on the
rest of the same line.  These arguments are the name of the node, and
the names of the `Next', `Previous', and `Up' pointers, in that order.
You may insert spaces before each pointer if you wish; the spaces are
ignored.  You must write the name of the node, and the names of the
`Next', `Previous', and `Up' pointers, all on the same line.  Otherwise,
the formatters fail.  (*note info: (info)Top, for more information
about nodes in Info.)

  Usually, you write one of the chapter-structuring command lines
immediately after an `@node' line--for example, an `@section' or
`@subsection' line.  (*Note Types of Structuring Commands: Structuring
Command Types.)

     *Please note:* The GNU Emacs Texinfo mode updating commands work
     only with Texinfo files in which `@node' lines are followed by
     chapter structuring lines.  *Note Updating Requirements::.

  TeX uses `@node' lines to identify the names to use for cross
references.  For this reason, you must write `@node' lines in a Texinfo
file that you intend to format for printing, even if you do not intend
to format it for Info.  (Cross references, such as the one at the end
of this sentence, are made with `@xref' and its related commands; see
*Note Cross References::.)

* Menu:

* Node Names::                  How to choose node and pointer names.
* Writing a Node::              How to write an `@node' line.
* Node Line Tips::              Keep names short.
* Node Line Requirements::      Keep names unique, without @-commands.
* First Node::                  How to write a `Top' node.
* makeinfo top command::        How to use the `@top' command.
* Top Node Summary::            Write a brief description for readers.

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File: texinfo.info,  Node: Node Names,  Next: Writing a Node,  Prev: node,  Up: node

Choosing Node and Pointer Names
-------------------------------

  The name of a node identifies the node.  The pointers enable you to
reach other nodes and consist of the names of those nodes.

  Normally, a node's `Up' pointer contains the name of the node whose
menu mentions that node.  The node's `Next' pointer contains the name
of the node that follows that node in that menu and its `Previous'
pointer contains the name of the node that precedes it in that menu.
When a node's `Previous' node is the same as its `Up' node, both node
pointers name the same node.

  Usually, the first node of a Texinfo file is the `Top' node, and its
`Up' and `Previous' pointers point to the `dir' file, which contains
the main menu for all of Info.

  The `Top' node itself contains the main or master menu for the manual.
Also, it is helpful to include a brief description of the manual in the
`Top' node.  *Note First Node::, for information on how to write the
first node of a Texinfo file.

\1f
File: texinfo.info,  Node: Writing a Node,  Next: Node Line Tips,  Prev: Node Names,  Up: node

How to Write an `@node' Line
----------------------------

The easiest way to write an `@node' line is to write `@node' at the
beginning of a line and then the name of the node, like this:

     @node NODE-NAME

  If you are using GNU Emacs, you can use the update node commands
provided by Texinfo mode to insert the names of the pointers; or you
can leave the pointers out of the Texinfo file and let `makeinfo'
insert node pointers into the Info file it creates.  (*Note Texinfo
Mode::, and *Note makeinfo Pointer Creation::.)

  Alternatively, you can insert the `Next', `Previous', and `Up'
pointers yourself.  If you do this, you may find it helpful to use the
Texinfo mode keyboard command `C-c C-c n'.  This command inserts
`@node' and a comment line listing the names of the pointers in their
proper order.  The comment line helps you keep track of which arguments
are for which pointers.  This comment line is especially useful if you
are not familiar with Texinfo.

  The template for a node line with `Next', `Previous', and `Up'
pointers looks like this:

     @node NODE-NAME, NEXT, PREVIOUS, UP

  If you wish, you can ignore `@node' lines altogether in your first
draft and then use the `texinfo-insert-node-lines' command to create
`@node' lines for you.  However, we do not recommend this practice.  It
is better to name the node itself at the same time that you write a
segment so you can easily make cross references.  A large number of
cross references are an especially important feature of a good Info
file.

  After you have inserted an `@node' line, you should immediately write
an @-command for the chapter or section and insert its name.  Next (and
this is important!), put in several index entries.  Usually, you will
find at least two and often as many as four or five ways of referring
to the node in the index.  Use them all.  This will make it much easier
for people to find the node.

\1f
File: texinfo.info,  Node: Node Line Tips,  Next: Node Line Requirements,  Prev: Writing a Node,  Up: node

`@node' Line Tips
-----------------

Here are three suggestions:

   * Try to pick node names that are informative but short.

     In the Info file, the file name, node name, and pointer names are
     all inserted on one line, which may run into the right edge of the
     window.  (This does not cause a problem with Info, but is ugly.)

   * Try to pick node names that differ from each other near the
     beginnings of their names.  This way, it is easy to use automatic
     name completion in Info.

   * By convention, node names are capitalized just as they would be for
     section or chapter titles--initial and significant words are
     capitalized; others are not.

\1f
File: texinfo.info,  Node: Node Line Requirements,  Next: First Node,  Prev: Node Line Tips,  Up: node

`@node' Line Requirements
-------------------------

Here are several requirements for `@node' lines:

   * All the node names for a single Info file must be unique.

     Duplicates confuse the Info movement commands.  This means, for
     example, that if you end every chapter with a summary, you must
     name each summary node differently.  You cannot just call each one
     "Summary".  You may, however, duplicate the titles of chapters,
     sections, and the like.  Thus you can end each chapter in a book
     with a section called "Summary", so long as the node names for
     those sections are all different.

   * A pointer name must be the name of a node.

     The node to which a pointer points may come before or after the
     node containing the pointer.

   * You cannot use any of the Texinfo @-commands in a node name;
     @-commands confuse Info.

     Thus, the beginning of the section called `@chapter' looks like
     this:

          @node  chapter, unnumbered & appendix, makeinfo top, Structuring
          @comment  node-name,  next,  previous,  up
          @section @code{@@chapter}
          @findex chapter

   * You cannot use commas or apostrophes within a node name; these
     confuse TeX or the Info formatters.

     For example, the following is a section title:

          @code{@@unnumberedsec}, @code{@@appendixsec}, @code{@@heading}

     The corresponding node name is:

          unnumberedsec appendixsec heading

   * Case is significant.

\1f
File: texinfo.info,  Node: First Node,  Next: makeinfo top command,  Prev: Node Line Requirements,  Up: node

The First Node
--------------

The first node of a Texinfo file is the "Top" node, except in an
included file (*note Include Files::).  The Top node contains the main
or master menu for the document, and a short summary of the document
(*note Top Node Summary::).

  The Top node (which must be named `top' or `Top') should have as its
`Up' node the name of a node in another file, where there is a menu
that leads to this file.  Specify the file name in parentheses.  If the
file is to be installed directly in the Info directory file, use
`(dir)' as the parent of the Top node; this is short for `(dir)top',
and specifies the Top node in the `dir' file, which contains the main
menu for the Info system as a whole.  For example, the `@node Top' line
of this manual looks like this:

     @node Top, Copying, , (dir)

(You can use the Texinfo updating commands or the `makeinfo' utility to
insert these pointers automatically.)

  Do not define the `Previous' node of the Top node to be `(dir)', as
it causes confusing behavior for users: if you are in the Top node and
hit <DEL> to go backwards, you wind up in the middle of some other
entry in the `dir' file, which has nothing to do with what you were
reading.

  *Note Install an Info File::, for more information about installing
an Info file in the `info' directory.

\1f
File: texinfo.info,  Node: makeinfo top command,  Next: Top Node Summary,  Prev: First Node,  Up: node

The `@top' Sectioning Command
-----------------------------

A special sectioning command, `@top', has been created for use with the
`@node Top' line.  The `@top' sectioning command tells `makeinfo' that
it marks the `Top' node in the file.  It provides the information that
`makeinfo' needs to insert node pointers automatically.  Write the
`@top' command at the beginning of the line immediately following the
`@node Top' line.  Write the title on the remaining part of the same
line as the `@top' command.

  In Info, the `@top' sectioning command causes the title to appear on a
line by itself, with a line of asterisks inserted underneath.

  In TeX and `texinfo-format-buffer', the `@top' sectioning command is
merely a synonym for `@unnumbered'.  Neither of these formatters
require an `@top' command, and do nothing special with it.  You can use
`@chapter' or `@unnumbered' after the `@node Top' line when you use
these formatters.  Also, you can use `@chapter' or `@unnumbered' when
you use the Texinfo updating commands to create or update pointers and
menus.

\1f
File: texinfo.info,  Node: Top Node Summary,  Prev: makeinfo top command,  Up: node

The `Top' Node Summary
----------------------

You can help readers by writing a summary in the `Top' node, after the
`@top' line, before the main or master menu.  The summary should
briefly describe the document.  In Info, this summary will appear just
before the master menu.  In a printed manual, this summary will appear
on a page of its own.

  If you do not want the summary to appear on a page of its own in a
printed manual, you can enclose the whole of the `Top' node, including
the `@node Top' line and the `@top' sectioning command line or other
sectioning command line between `@ifinfo' and `@end ifinfo'.  This
prevents any of the text from appearing in the printed output. (*note
Conditionally Visible Text: Conditionals.).  You can repeat the brief
description from the `Top' node within `@iftex' ... `@end iftex' at the
beginning of the first chapter, for those who read the printed manual.
This saves paper and may look neater.

  You should write the version number of the program to which the manual
applies in the summary.  This helps the reader keep track of which
manual is for which version of the program.  If the manual changes more
frequently than the program or is independent of it, you should also
include an edition number for the manual.  (The title page should also
contain this information: see *Note `@titlepage': titlepage.)

\1f
File: texinfo.info,  Node: makeinfo Pointer Creation,  Prev: node,  Up: Nodes

Creating Pointers with `makeinfo'
=================================

The `makeinfo' program has a feature for automatically creating node
pointers for a hierarchically organized file that lacks them.

  When you take advantage of this feature, you do not need to write the
`Next', `Previous', and `Up' pointers after the name of a node.
However, you must write a sectioning command, such as `@chapter' or
`@section', on the line immediately following each truncated `@node'
line.  You cannot write a comment line after a node line; the section
line must follow it immediately.

  In addition, you must follow the `Top' `@node' line with a line
beginning with `@top' to mark the `Top' node in the file. *Note `@top':
makeinfo top.

  Finally, you must write the name of each node (except for the `Top'
node) in a menu that is one or more hierarchical levels above the
node's hierarchical level.

  This node pointer insertion feature in `makeinfo' is an alternative
to the menu and pointer creation and update commands in Texinfo mode.
(*Note Updating Nodes and Menus::.)  It is especially helpful to people
who do not use GNU Emacs for writing Texinfo documents.

\1f
File: texinfo.info,  Node: Menus,  Next: Cross References,  Prev: Nodes,  Up: Top

Menus
*****

"Menus" contain pointers to subordinate nodes.(1) (*note
Menus-Footnote-1::) In Info, you use menus to go to such nodes.  Menus
have no effect in printed manuals and do not appear in them.

  By convention, a menu is put at the end of a node since a reader who
uses the menu may not see text that follows it.

  A node that has a menu should _not_ contain much text.  If you have a
lot of text and a menu, move most of the text into a new subnode--all
but a few lines.

* Menu:

* Menu Location::               Put a menu in a short node.
* Writing a Menu::              What is a menu?
* Menu Parts::                  A menu entry has three parts.
* Less Cluttered Menu Entry::   Two part menu entry.
* Menu Example::                Two and three part menu entries.
* Other Info Files::            How to refer to a different Info file.

\1f
File: texinfo.info,  Node: Menus-Footnotes,  Up: Menus

  (1) Menus can carry you to any node, regardless of the hierarchical
structure; even to nodes in a different Info file.  However, the GNU
Emacs Texinfo mode updating commands work only to create menus of
subordinate nodes.  Conventionally, cross references are used to refer
to other nodes.

\1f
File: texinfo.info,  Node: Menu Location,  Next: Writing a Menu,  Prev: Menus,  Up: Menus

Menus Need Short Nodes
======================

  A reader can easily see a menu that is close to the beginning of the
node.  The node should be short.  As a practical matter, you should
locate a menu within 20 lines of the beginning of the node.  Otherwise,
a reader with a terminal that displays only a few lines may miss the
menu and its associated text.

  The short text before a menu may look awkward in a printed manual.  To
avoid this, you can write a menu near the beginning of its node and
follow the menu by an `@node' line, and then an `@heading' line located
within `@ifinfo' and `@end ifinfo'.  This way, the menu, `@node' line,
and title appear only in the Info file, not the printed document.

  For example, the preceding two paragraphs follow an Info-only menu,
`@node' line, and heading, and look like this:

     @menu
     * Menu Location::             Put a menu in a short node.
     * Writing a Menu::            What is a menu?
     * Menu Parts::                A menu entry has three parts.
     * Less Cluttered Menu Entry:: Two part menu entry.
     * Menu Example::              Two and three part entries.
     * Other Info Files::          How to refer to a different
                                     Info file.
     @end menu
     
     @node Menu Location, Writing a Menu, , Menus
     @ifinfo
     @heading Menus Need Short Nodes
     @end ifinfo

  The Texinfo file for this document contains more than a dozen
examples of this procedure.  One is at the beginning of this chapter;
another is at the beginning of the "Cross References" chapter.

\1f
File: texinfo.info,  Node: Writing a Menu,  Next: Menu Parts,  Prev: Menu Location,  Up: Menus

Writing a Menu
==============

A menu consists of an `@menu' command on a line by itself followed by
menu entry lines or menu comment lines and then by an `@end menu'
command on a line by itself.

  A menu looks like this:

     @menu
     Larger Units of Text
     
     * Files::                       All about handling files.
     * Multiples: Buffers.           Multiple buffers; editing
                                       several files at once.
     @end menu

  In a menu, every line that begins with an `* ' is a "menu entry".
(Note the space after the asterisk.)  A line that does not start with
an `* ' may also appear in a menu.  Such a line is not a menu entry but
is a menu comment line that appears in the Info file.  In the example
above, the line `Larger Units of Text' is a menu comment line; the two
lines starting with `* ' are menu entries.

\1f
File: texinfo.info,  Node: Menu Parts,  Next: Less Cluttered Menu Entry,  Prev: Writing a Menu,  Up: Menus

The Parts of a Menu
===================

A menu entry has three parts, only the second of which is required:

  1. The menu entry name (optional).

  2. The name of the node (required).

  3. A description of the item (optional).

  The template for a menu entry looks like this:

     * MENU-ENTRY-NAME: NODE-NAME.   DESCRIPTION

  Follow the menu entry name with a single colon and follow the node
name with tab, comma, period, or newline.

  In Info, a user selects a node with the `m' (`Info-menu') command.
The menu entry name is what the user types after the `m' command.

  The third part of a menu entry is a descriptive phrase or sentence.
Menu entry names and node names are often short; the description
explains to the reader what the node is about.  A useful description
complements the node name rather than repeats it.  The description,
which is optional, can spread over two or more lines; if it does, some
authors prefer to indent the second line while others prefer to align it
with the first (and all others).  It's up to you.

\1f
File: texinfo.info,  Node: Less Cluttered Menu Entry,  Next: Menu Example,  Prev: Menu Parts,  Up: Menus

Less Cluttered Menu Entry
=========================

When the menu entry name and node name are the same, you can write the
name immediately after the asterisk and space at the beginning of the
line and follow the name with two colons.

  For example, write

     * Name::                                    DESCRIPTION

instead of

     * Name: Name.                               DESCRIPTION

  You should use the node name for the menu entry name whenever
possible, since it reduces visual clutter in the menu.

\1f
File: texinfo.info,  Node: Menu Example,  Next: Other Info Files,  Prev: Less Cluttered Menu Entry,  Up: Menus

A Menu Example
==============

A menu looks like this in Texinfo:

     @menu
     * menu entry name: Node name.   A short description.
     * Node name::                   This form is preferred.
     @end menu

This produces:

     * menu:
     
     * menu entry name: Node name.   A short description.
     * Node name::                   This form is preferred.

  Here is an example as you might see it in a Texinfo file:

     @menu
     Larger Units of Text
     
     * Files::                       All about handling files.
     * Multiples: Buffers.           Multiple buffers; editing
                                       several files at once.
     @end menu

This produces:

     * menu:
     Larger Units of Text
     
     * Files::                       All about handling files.
     * Multiples: Buffers.           Multiple buffers; editing
                                       several files at once.

  In this example, the menu has two entries.  `Files' is both a menu
entry name and the name of the node referred to by that name.
`Multiples' is the menu entry name; it refers to the node named
`Buffers'. The line `Larger Units of Text' is a comment; it appears in
the menu, but is not an entry.

  Since no file name is specified with either `Files' or `Buffers',
they must be the names of nodes in the same Info file (*note Referring
to Other Info Files: Other Info Files.).

\1f
File: texinfo.info,  Node: Other Info Files,  Prev: Menu Example,  Up: Menus

Referring to Other Info Files
=============================

You can create a menu entry that enables a reader in Info to go to a
node in another Info file by writing the file name in parentheses just
before the node name.  In this case, you should use the three-part menu
entry format, which saves the reader from having to type the file name.

  The format looks like this:

     @menu
     * FIRST-ENTRY-NAME:(FILENAME)NODENAME.     DESCRIPTION
     * SECOND-ENTRY-NAME:(FILENAME)SECOND-NODE. DESCRIPTION
     @end menu

  For example, to refer directly to the `Outlining' and `Rebinding'
nodes in the `XEmacs User's Manual', you would write a menu like this:

     @menu
     * Outlining: (xemacs)Outline Mode. The major mode for
                                        editing outlines.
     * Rebinding: (xemacs)Rebinding.    How to redefine the
                                        meaning of a key.
     @end menu

  If you do not list the node name, but only name the file, then Info
presumes that you are referring to the `Top' node.

  The `dir' file that contains the main menu for Info has menu entries
that list only file names.  These take you directly to the `Top' nodes
of each Info document.  (*Note Install an Info File::.)

  For example:

     * Info: (info).         Documentation browsing system.
     * Emacs: (emacs).       The extensible, self-documenting
                             text editor.

(The `dir' top level directory for the Info system is an Info file, not
a Texinfo file, but a menu entry looks the same in both types of file.)

  Note that the GNU Emacs Texinfo mode menu updating commands only work
with nodes within the current buffer, so you cannot use them to create
menus that refer to other files.  You must write such menus by hand.

\1f
File: texinfo.info,  Node: Cross References,  Next: Marking Text,  Prev: Menus,  Up: Top

Cross References
****************

"Cross references" are used to refer the reader to other parts of the
same or different Texinfo files.  In Texinfo, nodes are the places to
which cross references can refer.

* Menu:

* References::                  What cross references are for.
* Cross Reference Commands::    A summary of the different commands.
* Cross Reference Parts::       A cross reference has several parts.
* xref::                        Begin a reference with `See' ...
* Top Node Naming::             How to refer to the beginning of another file.
* ref::                         A reference for the last part of a sentence.
* pxref::                       How to write a parenthetical cross reference.
* inforef::                     How to refer to an Info-only file.
* uref::                        How to refer to a uniform resource locator.

\1f
File: texinfo.info,  Node: References,  Next: Cross Reference Commands,  Prev: Cross References,  Up: Cross References

What References Are For
=======================

  Often, but not always, a printed document should be designed so that
it can be read sequentially.  People tire of flipping back and forth to
find information that should be presented to them as they need it.

  However, in any document, some information will be too detailed for
the current context, or incidental to it; use cross references to
provide access to such information.  Also, an on-line help system or a
reference manual is not like a novel; few read such documents in
sequence from beginning to end.  Instead, people look up what they
need.  For this reason, such creations should contain many cross
references to help readers find other information that they may not
have read.

  In a printed manual, a cross reference results in a page reference,
unless it is to another manual altogether, in which case the cross
reference names that manual.

  In Info, a cross reference results in an entry that you can follow
using the Info `f' command.  (*note Some advanced Info commands:
(info)Help-Adv.)

  The various cross reference commands use nodes to define cross
reference locations.  This is evident in Info, in which a cross
reference takes you to the specified node.  TeX also uses nodes to
define cross reference locations, but the action is less obvious.  When
TeX generates a DVI file, it records nodes' page numbers and uses the
page numbers in making references.  Thus, if you are writing a manual
that will only be printed, and will not be used on-line, you must
nonetheless write `@node' lines to name the places to which you make
cross references.

\1f
File: texinfo.info,  Node: Cross Reference Commands,  Next: Cross Reference Parts,  Prev: References,  Up: Cross References

Different Cross Reference Commands
==================================

There are four different cross reference commands:

`@xref'
     Used to start a sentence in the printed manual saying `See ...'
     or an Info cross-reference saying `*Note NAME: NODE.'.

`@ref'
     Used within or, more often, at the end of a sentence; same as
     `@xref' for Info; produces just the reference in the printed
     manual without a preceding `See'.

`@pxref'
     Used within parentheses to make a reference that suits both an Info
     file and a printed book.  Starts with a lower case `see' within the
     printed manual. (`p' is for `parenthesis'.)

`@inforef'
     Used to make a reference to an Info file for which there is no
     printed manual.

(The `@cite' command is used to make references to books and manuals
for which there is no corresponding Info file and, therefore, no node
to which to point.   *Note `@cite': cite.)

\1f
File: texinfo.info,  Node: Cross Reference Parts,  Next: xref,  Prev: Cross Reference Commands,  Up: Cross References

Parts of a Cross Reference
==========================

A cross reference command requires only one argument, which is the name
of the node to which it refers.  But a cross reference command may
contain up to four additional arguments.  By using these arguments, you
can provide a cross reference name for Info, a topic description or
section title for the printed output, the name of a different Info
file, and the name of a different printed manual.

  Here is a simple cross reference example:

     @xref{Node name}.

which produces

     *Note Node name::.

and

     See Section NNN [Node name], page PPP.

  Here is an example of a full five-part cross reference:

     @xref{Node name, Cross Reference Name, Particular Topic,
     info-file-name, A Printed Manual}, for details.

which produces

     *Note Cross Reference Name: (info-file-name)Node name,
     for details.

in Info and

     See section "Particular Topic" in A Printed Manual, for details.

in a printed book.

  The five possible arguments for a cross reference are:

  1. The node name (required).  This is the node to which the cross
     reference takes you.  In a printed document, the location of the
     node provides the page reference only for references within the
     same document.

  2. The cross reference name for the Info reference, if it is to be
     different from the node name.  If you include this argument, it
     becomes the first part of the cross reference.  It is usually
     omitted.

  3. A topic description or section name.  Often, this is the title of
     the section.  This is used as the name of the reference in the
     printed manual.  If omitted, the node name is used.

  4. The name of the Info file in which the reference is located, if it
     is different from the current file.  You need not include any
     `.info' suffix on the file name, since Info readers try appending
     it automatically.

  5. The name of a printed manual from a different Texinfo file.

  The template for a full five argument cross reference looks like this:

     @xref{NODE-NAME, CROSS-REFERENCE-NAME, TITLE-OR-TOPIC,
     INFO-FILE-NAME, PRINTED-MANUAL-TITLE}.

  Cross references with one, two, three, four, and five arguments are
described separately following the description of `@xref'.

  Write a node name in a cross reference in exactly the same way as in
the `@node' line, including the same capitalization; otherwise, the
formatters may not find the reference.

  You can write cross reference commands within a paragraph, but note
how Info and TeX format the output of each of the various commands:
write `@xref' at the beginning of a sentence; write `@pxref' only
within parentheses, and so on.

\1f
File: texinfo.info,  Node: xref,  Next: Top Node Naming,  Prev: Cross Reference Parts,  Up: Cross References

`@xref'
=======

The `@xref' command generates a cross reference for the beginning of a
sentence.  The Info formatting commands convert it into an Info cross
reference, which the Info `f' command can use to bring you directly to
another node.  The TeX typesetting commands convert it into a page
reference, or a reference to another book or manual.

* Menu:

* Reference Syntax::            What a reference looks like and requires.
* One Argument::                `@xref' with one argument.
* Two Arguments::               `@xref' with two arguments.
* Three Arguments::             `@xref' with three arguments.
* Four and Five Arguments::     `@xref' with four and five arguments.

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File: texinfo.info,  Node: Reference Syntax,  Next: One Argument,  Prev: xref,  Up: xref

What a Reference Looks Like and Requires
----------------------------------------

  Most often, an Info cross reference looks like this:

     *Note NODE-NAME::.

or like this

     *Note CROSS-REFERENCE-NAME: NODE-NAME.

In TeX, a cross reference looks like this:

     See Section SECTION-NUMBER [NODE-NAME], page PAGE.

or like this

     See Section SECTION-NUMBER [TITLE-OR-TOPIC], page PAGE.

  The `@xref' command does not generate a period or comma to end the
cross reference in either the Info file or the printed output.  You
must write that period or comma yourself; otherwise, Info will not
recognize the end of the reference.  (The `@pxref' command works
differently.  *Note `@pxref': pxref.)

     *Please note:* A period or comma *must* follow the closing brace
     of an `@xref'.  It is required to terminate the cross reference.
     This period or comma will appear in the output, both in the Info
     file and in the printed manual.

  `@xref' must refer to an Info node by name.  Use `@node' to define
the node (*note Writing a Node::).

  `@xref' is followed by several arguments inside braces, separated by
commas.  Whitespace before and after these commas is ignored.

  A cross reference requires only the name of a node; but it may contain
up to four additional arguments.  Each of these variations produces a
cross reference that looks somewhat different.

     *Please note:* Commas separate arguments in a cross reference;
     avoid including them in the title or other part lest the formatters
     mistake them for separators.

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File: texinfo.info,  Node: One Argument,  Next: Two Arguments,  Prev: Reference Syntax,  Up: xref

`@xref' with One Argument
-------------------------

The simplest form of `@xref' takes one argument, the name of another
node in the same Info file.    The Info formatters produce output that
the Info readers can use to jump to the reference; TeX produces output
that specifies the page and section number for you.

For example,

     @xref{Tropical Storms}.

produces

     *Note Tropical Storms::.

and

     See Section 3.1 [Tropical Storms], page 24.

(Note that in the preceding example the closing brace is followed by a
period.)

  You can write a clause after the cross reference, like this:

     @xref{Tropical Storms}, for more info.

which produces

     *Note Tropical Storms::, for more info.

     See Section 3.1 [Tropical Storms], page 24, for more info.

(Note that in the preceding example the closing brace is followed by a
comma, and then by the clause, which is followed by a period.)

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File: texinfo.info,  Node: Two Arguments,  Next: Three Arguments,  Prev: One Argument,  Up: xref

`@xref' with Two Arguments
--------------------------

With two arguments, the second is used as the name of the Info cross
reference, while the first is still the name of the node to which the
cross reference points.

The template is like this:

     @xref{NODE-NAME, CROSS-REFERENCE-NAME}.

For example,

     @xref{Electrical Effects, Lightning}.

produces:

     *Note Lightning: Electrical Effects.

and

     See Section 5.2 [Electrical Effects], page 57.

(Note that in the preceding example the closing brace is followed by a
period; and that the node name is printed, not the cross reference
name.)

  You can write a clause after the cross reference, like this:

     @xref{Electrical Effects, Lightning}, for more info.

which produces
     *Note Lightning: Electrical Effects, for more info.

and

     See Section 5.2 [Electrical Effects], page 57, for more info.

(Note that in the preceding example the closing brace is followed by a
comma, and then by the clause, which is followed by a period.)

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File: texinfo.info,  Node: Three Arguments,  Next: Four and Five Arguments,  Prev: Two Arguments,  Up: xref

`@xref' with Three Arguments
----------------------------

A third argument replaces the node name in the TeX output.  The third
argument should be the name of the section in the printed output, or
else state the topic discussed by that section.  Often, you will want to
use initial upper case letters so it will be easier to read when the
reference is printed.  Use a third argument when the node name is
unsuitable because of syntax or meaning.

  Remember to avoid placing a comma within the title or topic section of
a cross reference, or within any other section.  The formatters divide
cross references into arguments according to the commas; a comma within
a title or other section will divide it into two arguments.  In a
reference, you need to write a title such as "Clouds, Mist, and Fog"
without the commas.

  Also, remember to write a comma or period after the closing brace of a
`@xref' to terminate the cross reference.  In the following examples, a
clause follows a terminating comma.

The template is like this:

     @xref{NODE-NAME, CROSS-REFERENCE-NAME, TITLE-OR-TOPIC}.

For example,

     @xref{Electrical Effects, Lightning, Thunder and Lightning},
     for details.

produces

     *Note Lightning: Electrical Effects, for details.

and

     See Section 5.2 [Thunder and Lightning], page 57, for details.

  If a third argument is given and the second one is empty, then the
third argument serves both.  (Note how two commas, side by side, mark
the empty second argument.)

     @xref{Electrical Effects, , Thunder and Lightning},
     for details.

produces

     *Note Thunder and Lightning: Electrical Effects, for details.

and

     See Section 5.2 [Thunder and Lightning], page 57, for details.

  As a practical matter, it is often best to write cross references with
just the first argument if the node name and the section title are the
same, and with the first and third arguments if the node name and title
are different.

  Here are several examples from `The GNU Awk User's Guide':

     @xref{Sample Program}.
     @xref{Glossary}.
     @xref{Case-sensitivity, ,Case-sensitivity in Matching}.
     @xref{Close Output, , Closing Output Files and Pipes},
        for more information.
     @xref{Regexp, , Regular Expressions as Patterns}.

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File: texinfo.info,  Node: Four and Five Arguments,  Prev: Three Arguments,  Up: xref

`@xref' with Four and Five Arguments
------------------------------------

In a cross reference, a fourth argument specifies the name of another
Info file, different from the file in which the reference appears, and
a fifth argument specifies its title as a printed manual.

  Remember that a comma or period must follow the closing brace of an
`@xref' command to terminate the cross reference.  In the following
examples, a clause follows a terminating comma.

The template is:

     @xref{NODE-NAME, CROSS-REFERENCE-NAME, TITLE-OR-TOPIC,
     INFO-FILE-NAME, PRINTED-MANUAL-TITLE}.

For example,

     @xref{Electrical Effects, Lightning, Thunder and Lightning,
     weather, An Introduction to Meteorology}, for details.

produces

     *Note Lightning: (weather)Electrical Effects, for details.

The name of the Info file is enclosed in parentheses and precedes the
name of the node.

In a printed manual, the reference looks like this:

     See section "Thunder and Lightning" in An Introduction to
     Meteorology, for details.

The title of the printed manual is typeset in italics; and the
reference lacks a page number since TeX cannot know to which page a
reference refers when that reference is to another manual.

  Often, you will leave out the second argument when you use the long
version of `@xref'.  In this case, the third argument, the topic
description, will be used as the cross reference name in Info.

The template looks like this:

     @xref{NODE-NAME, , TITLE-OR-TOPIC, INFO-FILE-NAME,
     PRINTED-MANUAL-TITLE}, for details.

which produces

     *Note TITLE-OR-TOPIC: (INFO-FILE-NAME)NODE-NAME, for details.

and

     See section TITLE-OR-TOPIC in PRINTED-MANUAL-TITLE, for details.

For example,

     @xref{Electrical Effects, , Thunder and Lightning,
     weather, An Introduction to Meteorology}, for details.

produces

     *Note Thunder and Lightning: (weather)Electrical Effects,
     for details.

and

     See section "Thunder and Lightning" in An Introduction to
     Meteorology, for details.

  On rare occasions, you may want to refer to another Info file that is
within a single printed manual--when multiple Texinfo files are
incorporated into the same TeX run but make separate Info files.  In
this case, you need to specify only the fourth argument, and not the
fifth.

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File: texinfo.info,  Node: Top Node Naming,  Next: ref,  Prev: xref,  Up: Cross References

Naming a `Top' Node
===================

In a cross reference, you must always name a node.  This means that in
order to refer to a whole manual, you must identify the `Top' node by
writing it as the first argument to the `@xref' command.  (This is
different from the way you write a menu entry; see *Note Referring to
Other Info Files: Other Info Files.)  At the same time, to provide a
meaningful section topic or title in the printed cross reference
(instead of the word `Top'), you must write an appropriate entry for
the third argument to the `@xref' command.

Thus, to make a cross reference to `The GNU Make Manual', write:

     @xref{Top, , Overview, make, The GNU Make Manual}.

which produces

     *Note Overview: (make)Top.

and

     See section "Overview" in The GNU Make Manual.

In this example, `Top' is the name of the first node, and `Overview' is
the name of the first section of the manual.

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File: texinfo.info,  Node: ref,  Next: pxref,  Prev: Top Node Naming,  Up: Cross References

`@ref'
======

`@ref' is nearly the same as `@xref' except that it does not generate a
`See' in the printed output, just the reference itself.  This makes it
useful as the last part of a sentence.

For example,

     For more information, see @ref{Hurricanes}.

produces

     For more information, see *Note Hurricanes::.

and

     For more information, see Section 8.2 [Hurricanes], page 123.

  The `@ref' command sometimes leads writers to express themselves in a
manner that is suitable for a printed manual but looks awkward in the
Info format.  Bear in mind that your audience will be using both the
printed and the Info format.

For example,

     Sea surges are described in @ref{Hurricanes}.

produces

     Sea surges are described in Section 6.7 [Hurricanes], page 72.

in a printed document, and the following in Info:

     Sea surges are described in *Note Hurricanes::.

     *Caution:* You _must_ write a period or comma immediately after an
     `@ref' command with two or more arguments.  Otherwise, Info will
     not find the end of the cross reference entry and its attempt to
     follow the cross reference will fail.  As a general rule, you
     should write a period or comma after every `@ref' command.  This
     looks best in both the printed and the Info output.

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File: texinfo.info,  Node: pxref,  Next: inforef,  Prev: ref,  Up: Cross References

`@pxref'
========

The parenthetical reference command, `@pxref', is nearly the same as
`@xref', but you use it _only_ inside parentheses and you do _not_ type
a comma or period after the command's closing brace.  The command
differs from `@xref' in two ways:

  1. TeX typesets the reference for the printed manual with a lower case
     `see' rather than an upper case `See'.

  2. The Info formatting commands automatically end the reference with a
     closing colon or period.

  Because one type of formatting automatically inserts closing
punctuation and the other does not, you should use `@pxref' _only_
inside parentheses as part of another sentence.  Also, you yourself
should not insert punctuation after the reference, as you do with
`@xref'.

  `@pxref' is designed so that the output looks right and works right
between parentheses both in printed output and in an Info file.  In a
printed manual, a closing comma or period should not follow a cross
reference within parentheses; such punctuation is wrong.  But in an
Info file, suitable closing punctuation must follow the cross reference
so Info can recognize its end.  `@pxref' spares you the need to use
complicated methods to put a terminator into one form of the output and
not the other.

With one argument, a parenthetical cross reference looks like this:

     ... storms cause flooding (@pxref{Hurricanes}) ...

which produces

     ... storms cause flooding (*Note Hurricanes::) ...

and

     ... storms cause flooding (see Section 6.7 [Hurricanes], page 72)
     ...

  With two arguments, a parenthetical cross reference has this template:

     ... (@pxref{NODE-NAME, CROSS-REFERENCE-NAME}) ...

which produces

     ... (*Note CROSS-REFERENCE-NAME: NODE-NAME.) ...

and

     ... (see Section NNN [NODE-NAME], page PPP) ...

  `@pxref' can be used with up to five arguments just like `@xref'
(*note `@xref': xref.).

     *Please note:* Use `@pxref' only as a parenthetical reference.  Do
     not try to use `@pxref' as a clause in a sentence.  It will look
     bad in either the Info file, the printed output, or both.

     Also, parenthetical cross references look best at the ends of
     sentences.  Although you may write them in the middle of a
     sentence, that location breaks up the flow of text.

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File: texinfo.info,  Node: inforef,  Next: uref,  Prev: pxref,  Up: Cross References

`@inforef'
==========

`@inforef' is used for cross references to Info files for which there
are no printed manuals.  Even in a printed manual, `@inforef' generates
a reference directing the user to look in an Info file.

  The command takes either two or three arguments, in the following
order:

  1. The node name.

  2. The cross reference name (optional).

  3. The Info file name.

Separate the arguments with commas, as with `@xref'.  Also, you must
terminate the reference with a comma or period after the `}', as you do
with `@xref'.

The template is:

     @inforef{NODE-NAME, CROSS-REFERENCE-NAME, INFO-FILE-NAME},

Thus,

     @inforef{Expert, Advanced Info commands, info},
     for more information.

produces

     *Note Advanced Info commands: (info)Expert,
     for more information.

and

     See Info file `info', node `Expert', for more information.

Similarly,

     @inforef{Expert, , info}, for more information.

produces

     *Note (info)Expert::, for more information.

and

     See Info file `info', node `Expert', for more information.

  The converse of `@inforef' is `@cite', which is used to refer to
printed works for which no Info form exists.  *Note `@cite': cite.

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File: texinfo.info,  Node: uref,  Prev: inforef,  Up: Cross References

`@uref{URL[, DISPLAYED-TEXT]}'
==============================

`@uref' produces a reference to a uniform resource locator (URL).  It
takes one mandatory argument, the URL, and one optional argument, the
text to display (the default is the URL itself).  In HTML output,
`@uref' produces a link you can follow.  For example:

     The official GNU ftp site is
     @uref{ftp://ftp.gnu.ai.mit.edu/pub/gnu}

produces (in text):
     The official GNU ftp site is
     `ftp://ftp.gnu.ai.mit.edu/pub/gnu'

whereas
     The official
     @uref{ftp://ftp.gnu.ai.mit.edu/pub/gnu,
       GNU ftp site} holds programs and texts.

produces (in text):
     The official GNU ftp site (ftp://ftp.gnu.ai.mit.edu/pub/gnu) holds
     programs and texts.

and (in HTML):
     The official <A HREF="ftp://ftp.gnu.ai.mit.edu/pub/gnu">GNU ftp
     site</A> holds programs and texts.

  To merely indicate a URL, use `@url' (*note `@url': url.).

\1f
File: texinfo.info,  Node: Marking Text,  Next: Quotations and Examples,  Prev: Cross References,  Up: Top

Marking Words and Phrases
*************************

In Texinfo, you can mark words and phrases in a variety of ways.  The
Texinfo formatters use this information to determine how to highlight
the text.  You can specify, for example, whether a word or phrase is a
defining occurrence, a metasyntactic variable, or a symbol used in a
program.  Also, you can emphasize text.

* Menu:

* Indicating::                  How to indicate definitions, files, etc.
* Emphasis::                    How to emphasize text.

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File: texinfo.info,  Node: Indicating,  Next: Emphasis,  Prev: Marking Text,  Up: Marking Text

Indicating Definitions, Commands, etc.
======================================

Texinfo has commands for indicating just what kind of object a piece of
text refers to.  For example, metasyntactic variables are marked by
`@var', and code by `@code'.  Since the pieces of text are labelled by
commands that tell what kind of object they are, it is easy to change
the way the Texinfo formatters prepare such text.  (Texinfo is an
_intentional_ formatting language rather than a _typesetting_
formatting language.)

  For example, in a printed manual, code is usually illustrated in a
typewriter font; `@code' tells TeX to typeset this text in this font.
But it would be easy to change the way TeX highlights code to use
another font, and this change would not effect how keystroke examples
are highlighted.  If straight typesetting commands were used in the body
of the file and you wanted to make a change, you would need to check
every single occurrence to make sure that you were changing code and
not something else that should not be changed.

* Menu:

* Useful Highlighting::         Highlighting provides useful information.
* code::                        How to indicate code.
* kbd::                         How to show keyboard input.
* key::                         How to specify keys.
* samp::                        How to show a literal sequence of characters.
* var::                         How to indicate a metasyntactic variable.
* file::                        How to indicate the name of a file.
* dfn::                         How to specify a definition.
* cite::                        How to refer to a book that is not in Info.
* url::                         How to indicate a world wide web reference.
* email::                       How to indicate an electronic mail address.

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File: texinfo.info,  Node: Useful Highlighting,  Next: code,  Prev: Indicating,  Up: Indicating

Highlighting Commands are Useful
--------------------------------

  The highlighting commands can be used to generate useful information
from the file, such as lists of functions or file names.  It is
possible, for example, to write a program in Emacs Lisp (or a keyboard
macro) to insert an index entry after every paragraph that contains
words or phrases marked by a specified command.  You could do this to
construct an index of functions if you had not already made the entries.

  The commands serve a variety of purposes:

`@code{SAMPLE-CODE}'
     Indicate text that is a literal example of a piece of a program.

`@kbd{KEYBOARD-CHARACTERS}'
     Indicate keyboard input.

`@key{KEY-NAME}'
     Indicate the conventional name for a key on a keyboard.

`@samp{TEXT}'
     Indicate text that is a literal example of a sequence of
     characters.

`@var{METASYNTACTIC-VARIABLE}'
     Indicate a metasyntactic variable.

`@url{UNIFORM-RESOURCE-LOCATOR}'
     Indicate a uniform resource locator for the World Wide Web.

`@file{FILE-NAME}'
     Indicate the name of a file.

`@email{EMAIL-ADDRESS[, DISPLAYED-TEXT]}'
     Indicate an electronic mail address.

`@dfn{TERM}'
     Indicate the introductory or defining use of a term.

`@cite{REFERENCE}'
     Indicate the name of a book.


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File: texinfo.info,  Node: code,  Next: kbd,  Prev: Useful Highlighting,  Up: Indicating

`@code'{SAMPLE-CODE}
--------------------

Use the `@code' command to indicate text that is a piece of a program
and which consists of entire syntactic tokens.  Enclose the text in
braces.

  Thus, you should use `@code' for an expression in a program, for the
name of a variable or function used in a program, or for a keyword.
Also, you should use `@code' for the name of a program, such as `diff',
that is a name used in the machine. (You should write the name of a
program in the ordinary text font if you regard it as a new English
word, such as `Emacs' or `Bison'.)

  Use `@code' for environment variables such as `TEXINPUTS', and other
variables.

  Use `@code' for command names in command languages that resemble
programming languages, such as Texinfo or the shell.  For example,
`@code' and `@samp' are produced by writing `@code{@@code}' and
`@code{@@samp}' in the Texinfo source, respectively.

  Note, however, that you should not use `@code' for shell options such
as `-c' when such options stand alone. (Use `@samp'.)  Also, an entire
shell command often looks better if written using `@samp' rather than
`@code'.  In this case, the rule is to choose the more pleasing format.

  It is incorrect to alter the case of a word inside an `@code' command
when it appears at the beginning of a sentence.  Most computer
languages are case sensitive.  In C, for example, `Printf' is different
from the identifier `printf', and most likely is a misspelling of it.
Even in languages which are not case sensitive, it is confusing to a
human reader to see identifiers spelled in different ways.  Pick one
spelling and always use that.  If you do not want to start a sentence
with a command written all in lower case, you should rearrange the
sentence.

  Do not use the `@code' command for a string of characters shorter
than a syntactic token.  If you are writing about `TEXINPU', which is
just a part of the name for the `TEXINPUTS' environment variable, you
should use `@samp'.

  In particular, you should not use the `@code' command when writing
about the characters used in a token; do not, for example, use `@code'
when you are explaining what letters or printable symbols can be used
in the names of functions.  (Use `@samp'.)  Also, you should not use
`@code' to mark text that is considered input to programs unless the
input is written in a language that is like a programming language.
For example, you should not use `@code' for the keystroke commands of
GNU Emacs (use `@kbd' instead) although you may use `@code' for the
names of the Emacs Lisp functions that the keystroke commands invoke.

  In the printed manual, `@code' causes TeX to typeset the argument in
a typewriter face.  In the Info file, it causes the Info formatting
commands to use single quotation marks around the text.

  For example,

     Use @code{diff} to compare two files.

produces this in the printed manual:

     Use `diff' to compare two files.

\1f
File: texinfo.info,  Node: kbd,  Next: key,  Prev: code,  Up: Indicating

`@kbd'{KEYBOARD-CHARACTERS}
---------------------------

Use the `@kbd' command for characters of input to be typed by users.
For example, to refer to the characters `M-a', write

     @kbd{M-a}

and to refer to the characters `M-x shell', write

     @kbd{M-x shell}

  The `@kbd' command has the same effect as `@code' in Info, but by
default produces a different font (slanted typewriter instead of normal
typewriter) in the printed manual, so users can distinguish the
characters they are supposed to type from those the computer outputs.

  Since the usage of `@kbd' varies from manual to manual, you can
control the font switching with the `@kbdinputstyle' command.  This
command has no effect on Info output.  Write this command at the
beginning of a line with a single word as an argument, one of the
following:
`code'
     Always use the same font for `@kbd' as `@code'.

`example'
     Use the distinguishing font for `@kbd' only in `@example' and
     similar environments.

`example'
     (the default) Always use the distinguishing font for `@kbd'.

  You can embed another @-command inside the braces of an `@kbd'
command.  Here, for example, is the way to describe a command that
would be described more verbosely as "press an `r' and then press the
<RET> key":

     @kbd{r @key{RET}}

This produces: `r <RET>'

  You also use the `@kbd' command if you are spelling out the letters
you type; for example:

     To give the @code{logout} command,
     type the characters @kbd{l o g o u t @key{RET}}.

This produces:

     To give the `logout' command, type the characters `l o g o u t
     <RET>'.

  (Also, this example shows that you can add spaces for clarity.  If you
really want to mention a space character as one of the characters of
input, write `@key{SPC}' for it.)

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File: texinfo.info,  Node: key,  Next: samp,  Prev: kbd,  Up: Indicating

`@key'{KEY-NAME}
----------------

Use the `@key' command for the conventional name for a key on a
keyboard, as in:

     @key{RET}

  You can use the `@key' command within the argument of an `@kbd'
command when the sequence of characters to be typed includes one or
more keys that are described by name.

  For example, to produce `C-x <ESC>' you would type:

     @kbd{C-x @key{ESC}}

  Here is a list of the recommended names for keys:

    SPC
          Space

    RET
          Return

    LFD
          Linefeed (however, since most keyboards nowadays do not have
          a Linefeed key, it might be better to call this character
          `C-j'.

    TAB
          Tab

    BS
          Backspace

    ESC
          Escape

    DEL
          Delete

    SHIFT
          Shift

    CTRL
          Control

    META
          Meta

  There are subtleties to handling words like `meta' or `ctrl' that are
names of modifier keys.  When mentioning a character in which the
modifier key is used, such as `Meta-a', use the `@kbd' command alone;
do not use the `@key' command; but when you are referring to the
modifier key in isolation, use the `@key' command.  For example, write
`@kbd{Meta-a}' to produce `Meta-a' and `@key{META}' to produce <META>.

\1f
File: texinfo.info,  Node: samp,  Next: var,  Prev: key,  Up: Indicating

`@samp'{TEXT}
-------------

Use the `@samp' command to indicate text that is a literal example or
`sample' of a sequence of characters in a file, string, pattern, etc.
Enclose the text in braces.  The argument appears within single
quotation marks in both the Info file and the printed manual; in
addition, it is printed in a fixed-width font.

     To match @samp{foo} at the end of the line,
     use the regexp @samp{foo$}.

produces

     To match `foo' at the end of the line, use the regexp `foo$'.

  Any time you are referring to single characters, you should use
`@samp' unless `@kbd' or `@key' is more appropriate.  Use `@samp' for
the names of command-line options (except in an `@table', where `@code'
seems to read more easily).  Also, you may use `@samp' for entire
statements in C and for entire shell commands--in this case, `@samp'
often looks better than `@code'.  Basically, `@samp' is a catchall for
whatever is not covered by `@code', `@kbd', or `@key'.

  Only include punctuation marks within braces if they are part of the
string you are specifying.  Write punctuation marks outside the braces
if those punctuation marks are part of the English text that surrounds
the string.  In the following sentence, for example, the commas and
period are outside of the braces:

     In English, the vowels are @samp{a}, @samp{e},
     @samp{i}, @samp{o}, @samp{u}, and sometimes
     @samp{y}.

This produces:

     In English, the vowels are `a', `e', `i', `o', `u',  and sometimes
     `y'.

\1f
File: texinfo.info,  Node: var,  Next: file,  Prev: samp,  Up: Indicating

`@var'{METASYNTACTIC-VARIABLE}
------------------------------

Use the `@var' command to indicate metasyntactic variables.  A
"metasyntactic variable" is something that stands for another piece of
text.  For example, you should use a metasyntactic variable in the
documentation of a function to describe the arguments that are passed
to that function.

  Do not use `@var' for the names of particular variables in
programming languages.  These are specific names from a program, so
`@code' is correct for them.  For example, the Emacs Lisp variable
`texinfo-tex-command' is not a metasyntactic variable; it is properly
formatted using `@code'.

  The effect of `@var' in the Info file is to change the case of the
argument to all upper case; in the printed manual, to italicize it.

  For example,

     To delete file @var{filename},
     type @code{rm @var{filename}}.

produces

     To delete file FILENAME, type `rm FILENAME'.

(Note that `@var' may appear inside `@code', `@samp', `@file', etc.)

  Write a metasyntactic variable all in lower case without spaces, and
use hyphens to make it more readable.  Thus, the Texinfo source for the
illustration of how to begin a Texinfo manual looks like this:

     \input texinfo
     @@setfilename @var{info-file-name}
     @@settitle @var{name-of-manual}

This produces:

     \input texinfo
     @setfilename INFO-FILE-NAME
     @settitle NAME-OF-MANUAL

  In some documentation styles, metasyntactic variables are shown with
angle brackets, for example:

     ..., type rm <filename>

However, that is not the style that Texinfo uses.  (You can, of course,
modify the sources to TeX and the Info formatting commands to output
the `<...>' format if you wish.)

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File: texinfo.info,  Node: file,  Next: dfn,  Prev: var,  Up: Indicating

`@file'{FILE-NAME}
------------------

Use the `@file' command to indicate text that is the name of a file,
buffer, or directory, or is the name of a node in Info.  You can also
use the command for file name suffixes.  Do not use `@file' for symbols
in a programming language; use `@code'.

  Currently, `@file' is equivalent to `@samp' in its effects.  For
example,

     The @file{.el} files are in
     the @file{/usr/local/emacs/lisp} directory.

produces

     The `.el' files are in the `/usr/local/emacs/lisp' directory.

\1f
File: texinfo.info,  Node: dfn,  Next: cite,  Prev: file,  Up: Indicating

`@dfn'{TERM}
------------

Use the `@dfn' command to identify the introductory or defining use of
a technical term.  Use the command only in passages whose purpose is to
introduce a term which will be used again or which the reader ought to
know.  Mere passing mention of a term for the first time does not
deserve `@dfn'.  The command generates italics in the printed manual,
and double quotation marks in the Info file.  For example:

     Getting rid of a file is called @dfn{deleting} it.

produces

     Getting rid of a file is called "deleting" it.

  As a general rule, a sentence containing the defining occurrence of a
term should be a definition of the term.  The sentence does not need to
say explicitly that it is a definition, but it should contain the
information of a definition--it should make the meaning clear.

\1f
File: texinfo.info,  Node: cite,  Next: url,  Prev: dfn,  Up: Indicating

`@cite'{REFERENCE}
------------------

Use the `@cite' command for the name of a book that lacks a companion
Info file. The command produces italics in the printed manual, and
quotation marks in the Info file.

  (If a book is written in Texinfo, it is better to use a cross
reference command since a reader can easily follow such a reference in
Info.  *Note `@xref': xref.)

\1f
File: texinfo.info,  Node: url,  Next: email,  Prev: cite,  Up: Indicating

`@url'{UNIFORM-RESOURCE-LOCATOR}
--------------------------------

Use the `@url' to indicate a uniform resource locator on the World Wide
Web.  This is analogous to `@file', `@var', etc., and is purely for
markup purposes.  It does not produce a link you can follow in HTML
output (the `@uref' command does, *note `@uref': uref.).  It is useful
for example URL's which do not actually exist.  For example:

     For example, the url might be
     @url{http://host.domain.org/path}.

\1f
File: texinfo.info,  Node: email,  Prev: url,  Up: Indicating

`@email'{EMAIL-ADDRESS[, DISPLAYED-TEXT]}
-----------------------------------------

Use the `@email' command to indicate an electronic mail address.  It
takes one mandatory argument, the address, and one optional argument,
the text to display (the default is the address itself).

  In Info and TeX, the address is shown in angle brackets, preceded by
the text to display if any.  In HTML output, `@email' produces a
`mailto' link that usually brings up a mail composition window.  For
example:

     Send bug reports to @email{bug-texinfo@@gnu.org}.
     Send suggestions to the @email{bug-texinfo@@gnu.org, same place}.

produces
     Send bug reports to <bug-texinfo@gnu.org>.
     Send suggestions to the same place <bug-texinfo@gnu.org>.

\1f
File: texinfo.info,  Node: Emphasis,  Prev: Indicating,  Up: Marking Text

Emphasizing Text
================

Usually, Texinfo changes the font to mark words in the text according to
what category the words belong to; an example is the `@code' command.
Most often, this is the best way to mark words.  However, sometimes you
will want to emphasize text without indicating a category.  Texinfo has
two commands to do this.  Also, Texinfo has several commands that
specify the font in which TeX will typeset text.  These commands have
no affect on Info and only one of them, the `@r' command, has any
regular use.

* Menu:

* emph & strong::               How to emphasize text in Texinfo.
* Smallcaps::                   How to use the small caps font.
* Fonts::                       Various font commands for printed output.
* Customized Highlighting::     How to define highlighting commands.

\1f
File: texinfo.info,  Node: emph & strong,  Next: Smallcaps,  Prev: Emphasis,  Up: Emphasis

`@emph'{TEXT} and `@strong'{TEXT}
---------------------------------

The `@emph' and `@strong' commands are for emphasis; `@strong' is
stronger.  In printed output, `@emph' produces _italics_ and `@strong'
produces *bold*.

  For example,

     @quotation
     @strong{Caution:} @samp{rm * .[^.]*} removes @emph{all}
     files in the directory.
     @end quotation

produces:

          *Caution*: `rm * .[^.]*' removes *all*
          files in the directory.

  The `@strong' command is seldom used except to mark what is, in
effect, a typographical element, such as the word `Caution' in the
preceding example.

  In the Info file, both `@emph' and `@strong' put asterisks around the
text.

     *Caution:* Do not use `@emph' or `@strong' with the word `Note';
     Info will mistake the combination for a cross reference.  Use a
     phrase such as *Please note* or *Caution* instead.

\1f
File: texinfo.info,  Node: Smallcaps,  Next: Fonts,  Prev: emph & strong,  Up: Emphasis

`@sc'{TEXT}: The Small Caps Font
--------------------------------

Use the `@sc' command to set text in the printed output in a small caps
font and set text in the Info file in upper case letters.

Write the text between braces in lower case, like this:

     The @sc{acm} and @sc{ieee} are technical societies.

This produces:

     The ACM and IEEE are technical societies.

  TeX typesets the small caps font in a manner that prevents the
letters from `jumping out at you on the page'.  This makes small caps
text easier to read than text in all upper case.  The Info formatting
commands set all small caps text in upper case.

  If the text between the braces of an `@sc' command is upper case, TeX
typesets in full-size capitals.  Use full-size capitals sparingly.

  You may also use the small caps font for a jargon word such as ATO (a
NASA word meaning `abort to orbit').

  There are subtleties to using the small caps font with a jargon word
such as CDR, a word used in Lisp programming.  In this case, you should
use the small caps font when the word refers to the second and
subsequent elements of a list (the CDR of the list), but you should use
`@code' when the word refers to the Lisp function of the same spelling.

\1f
File: texinfo.info,  Node: Fonts,  Next: Customized Highlighting,  Prev: Smallcaps,  Up: Emphasis

Fonts for Printing, Not Info
----------------------------

Texinfo provides four font commands that specify font changes in the
printed manual but have no effect in the Info file.  `@i' requests
italic font (in some versions of TeX, a slanted font is used), `@b'
requests bold face, `@t' requests the fixed-width, typewriter-style
font used by `@code', and `@r' requests a roman font, which is the
usual font in which text is printed.  All four commands apply to an
argument that follows, surrounded by braces.

  Only the `@r' command has much use: in example programs, you can use
the `@r' command to convert code comments from the fixed-width font to
a roman font.  This looks better in printed output.

  For example,

     @lisp
     (+ 2 2)    ; @r{Add two plus two.}
     @end lisp

produces

     (+ 2 2)    ; Add two plus two.

  If possible, you should avoid using the other three font commands.  If
you need to use one, it probably indicates a gap in the Texinfo
language.

\1f
File: texinfo.info,  Node: Customized Highlighting,  Prev: Fonts,  Up: Emphasis

Customized Highlighting
-----------------------

You can use regular TeX commands inside of `@iftex' ...  `@end iftex'
to create your own customized highlighting commands for Texinfo.  The
easiest way to do this is to equate your customized commands with
pre-existing commands, such as those for italics.  Such new commands
work only with TeX.

  You can use the `@definfoenclose' command inside of `@ifinfo' ...
`@end ifinfo' to define commands for Info with the same names as new
commands for TeX.  `@definfoenclose' creates new commands for Info that
mark text by enclosing it in strings that precede and follow the text.
(1) (*note Customized Highlighting-Footnote-1::)

  Here is how to create a new @-command called `@phoo' that causes TeX
to typeset its argument in italics and causes Info to display the
argument between `//' and `\\'.

  For TeX, write the following to equate the `@phoo' command with the
existing `@i' italics command:

     @iftex
     @global@let@phoo=@i
     @end iftex

This defines `@phoo' as a command that causes TeX to typeset the
argument to `@phoo' in italics.  `@global@let' tells TeX to equate the
next argument with the argument that follows the equals sign.

  For Info, write the following to tell the Info formatters to enclose
the argument between `//' and `\\':

     @ifinfo
     @definfoenclose phoo, //, \\
     @end ifinfo

Write the `@definfoenclose' command on a line and follow it with three
arguments separated by commas (commas are used as separators in an
`@node' line in the same way).

   * The first argument to `@definfoenclose' is the @-command name
     *without* the `@';

   * the second argument is the Info start delimiter string; and,

   * the third argument is the Info end delimiter string.

The latter two arguments enclose the highlighted text in the Info file.
A delimiter string may contain spaces.  Neither the start nor end
delimiter is required.  However, if you do not provide a start
delimiter, you must follow the command name with two commas in a row;
otherwise, the Info formatting commands will misinterpret the end
delimiter string as a start delimiter string.

  After you have defined `@phoo' both for TeX and for Info, you can
then write `@phoo{bar}' to see `//bar\\' in Info and see `bar' in
italics in printed output.

  Note that each definition applies to its own formatter: one for TeX,
the other for Info.

  Here is another example:

     @ifinfo
     @definfoenclose headword, , :
     @end ifinfo
     @iftex
     @global@let@headword=@b
     @end iftex

This defines `@headword' as an Info formatting command that inserts
nothing before and a colon after the argument and as a TeX formatting
command to typeset its argument in bold.

\1f
File: texinfo.info,  Node: Customized Highlighting-Footnotes,  Up: Customized Highlighting

  (1) Currently, `@definfoenclose' works only with
`texinfo-format-buffer' and `texinfo-format-region', not with
`makeinfo'.

\1f
File: texinfo.info,  Node: Quotations and Examples,  Next: Lists and Tables,  Prev: Marking Text,  Up: Top

Quotations and Examples
***********************

Quotations and examples are blocks of text consisting of one or more
whole paragraphs that are set off from the bulk of the text and treated
differently.  They are usually indented.

  In Texinfo, you always begin a quotation or example by writing an
@-command at the beginning of a line by itself, and end it by writing
an `@end' command that is also at the beginning of a line by itself.
For instance, you begin an example by writing `@example' by itself at
the beginning of a line and end the example by writing `@end example'
on a line by itself, at the beginning of that line.

* Menu:

* Block Enclosing Commands::    Use different constructs for
                                  different purposes.
* quotation::                   How to write a quotation.
* example::                     How to write an example in a fixed-width font.
* noindent::                    How to prevent paragraph indentation.
* Lisp Example::                How to illustrate Lisp code.
* smallexample & smalllisp::    Forms for the `@smallbook' option.
* display::                     How to write an example in the current font.
* format::                      How to write an example that does not narrow
                                  the margins.
* exdent::                      How to undo the indentation of a line.
* flushleft & flushright::      How to push text flushleft or flushright.
* cartouche::                   How to draw cartouches around examples.

\1f
File: texinfo.info,  Node: Block Enclosing Commands,  Next: quotation,  Prev: Quotations and Examples,  Up: Quotations and Examples

The Block Enclosing Commands
============================

Here are commands for quotations and examples:

`@quotation'
     Indicate text that is quoted. The text is filled, indented, and
     printed in a roman font by default.

`@example'
     Illustrate code, commands, and the like. The text is printed in a
     fixed-width font, and indented but not filled.

`@lisp'
     Illustrate Lisp code. The text is printed in a fixed-width font,
     and indented but not filled.

`@smallexample'
     Illustrate code, commands, and the like.  Similar to `@example',
     except that in TeX this command typesets text in a smaller font
     for the smaller `@smallbook' format than for the 8.5 by 11 inch
     format.

`@smalllisp'
     Illustrate Lisp code.  Similar to `@lisp', except that in TeX this
     command typesets text in a smaller font for the smaller
     `@smallbook' format than for the 8.5 by 11 inch format.

`@display'
     Display illustrative text.  The text is indented but not filled,
     and no font is specified (so, by default, the font is roman).

`@format'
     Print illustrative text.  The text is not indented and not filled
     and no font is specified (so, by default, the font is roman).

  The `@exdent' command is used within the above constructs to undo the
indentation of a line.

  The `@flushleft' and `@flushright' commands are used to line up the
left or right margins of unfilled text.

  The `@noindent' command may be used after one of the above constructs
to prevent the following text from being indented as a new paragraph.

  You can use the `@cartouche' command within one of the above
constructs to highlight the example or quotation by drawing a box with
rounded corners around it.  (The `@cartouche' command affects only the
printed manual; it has no effect in the Info file; see *Note Drawing
Cartouches Around Examples: cartouche.)

\1f
File: texinfo.info,  Node: quotation,  Next: example,  Prev: Block Enclosing Commands,  Up: Quotations and Examples

`@quotation'
============

The text of a quotation is processed normally except that:

   * the margins are closer to the center of the page, so the whole of
     the quotation is indented;

   * the first lines of paragraphs are indented no more than other
     lines;

   * in the printed output, interparagraph spacing is reduced.

     This is an example of text written between an `@quotation' command
     and an `@end quotation' command.  An `@quotation' command is most
     often used to indicate text that is excerpted from another (real
     or hypothetical) printed work.

  Write an `@quotation' command as text on a line by itself.  This line
will disappear from the output.  Mark the end of the quotation with a
line beginning with and containing only `@end quotation'.  The `@end
quotation' line will likewise disappear from the output.  Thus, the
following,

     @quotation
     This is
     a foo.
     @end quotation

produces

     This is a foo.

\1f
File: texinfo.info,  Node: example,  Next: noindent,  Prev: quotation,  Up: Quotations and Examples

`@example'
==========

The `@example' command is used to indicate an example that is not part
of the running text, such as computer input or output.

     This is an example of text written between an
     `@example' command
     and an `@end example' command.
     The text is indented but not filled.
     
     In the printed manual, the text is typeset in a
     fixed-width font, and extra spaces and blank lines are
     significant.  In the Info file, an analogous result is
     obtained by indenting each line with five spaces.

  Write an `@example' command at the beginning of a line by itself.
This line will disappear from the output.  Mark the end of the example
with an `@end example' command, also written at the beginning of a line
by itself.  The `@end example' will disappear from the output.

  For example,

     @example
     mv foo bar
     @end example

produces

     mv foo bar

  Since the lines containing `@example' and `@end example' will
disappear, you should put a blank line before the `@example' and
another blank line after the `@end example'.  (Remember that blank
lines between the beginning `@example' and the ending `@end example'
will appear in the output.)

     *Caution:* Do not use tabs in the lines of an example (or anywhere
     else in Texinfo, for that matter)!  TeX treats tabs as single
     spaces, and that is not what they look like.  This is a problem
     with TeX.  (If necessary, in Emacs, you can use `M-x untabify' to
     convert tabs in a region to multiple spaces.)

  Examples are often, logically speaking, "in the middle" of a
paragraph, and the text continues after an example should not be
indented.  The `@noindent' command prevents a piece of text from being
indented as if it were a new paragraph.  (*Note noindent::.)

  (The `@code' command is used for examples of code that are embedded
within sentences, not set off from preceding and following text.  *Note
`@code': code.)

\1f
File: texinfo.info,  Node: noindent,  Next: Lisp Example,  Prev: example,  Up: Quotations and Examples

`@noindent'
===========

An example or other inclusion can break a paragraph into segments.
Ordinarily, the formatters indent text that follows an example as a new
paragraph.  However, you can prevent this by writing `@noindent' at the
beginning of a line by itself preceding the continuation text.

  For example:

     @example
     This is an example
     @end example
     
     @noindent
     This line is not indented.  As you can see, the
     beginning of the line is fully flush left with the line
     that follows after it.  (This whole example is between
     @code{@@display} and @code{@@end display}.)

produces

          This is an example
     
     
     This line is not indented.  As you can see, the
     beginning of the line is fully flush left with the line
     that follows after it.  (This whole example is between
     `@display' and `@end display'.)

  To adjust the number of blank lines properly in the Info file output,
remember that the line containing `@noindent' does not generate a blank
line, and neither does the `@end example' line.

  In the Texinfo source file for this manual, each line that says
`produces' is preceded by a line containing `@noindent'.

  Do not put braces after an `@noindent' command; they are not
necessary, since `@noindent' is a command used outside of paragraphs
(*note Command Syntax::).

\1f
File: texinfo.info,  Node: Lisp Example,  Next: smallexample & smalllisp,  Prev: noindent,  Up: Quotations and Examples

`@lisp'
=======

The `@lisp' command is used for Lisp code.  It is synonymous with the
`@example' command.

     This is an example of text written between an
     `@lisp' command and an `@end lisp' command.

  Use `@lisp' instead of `@example' to preserve information regarding
the nature of the example.  This is useful, for example, if you write a
function that evaluates only and all the Lisp code in a Texinfo file.
Then you can use the Texinfo file as a Lisp library.(1) (*note Lisp
Example-Footnote-1::)

  Mark the end of `@lisp' with `@end lisp' on a line by itself.

\1f
File: texinfo.info,  Node: Lisp Example-Footnotes,  Up: Lisp Example

  (1) It would be straightforward to extend Texinfo to work in a
similar fashion for C, Fortran, or other languages.

\1f
File: texinfo.info,  Node: smallexample & smalllisp,  Next: display,  Prev: Lisp Example,  Up: Quotations and Examples

`@smallexample' and `@smalllisp'
================================

In addition to the regular `@example' and `@lisp' commands, Texinfo has
two other "example-style" commands.  These are the `@smallexample' and
`@smalllisp' commands.  Both these commands are designed for use with
the `@smallbook' command that causes TeX to produce a printed manual in
a 7 by 9.25 inch format rather than the regular 8.5 by 11 inch format.

  In TeX, the `@smallexample' and `@smalllisp' commands typeset text in
a smaller font for the smaller `@smallbook' format than for the 8.5 by
11 inch format.  Consequently, many examples containing long lines fit
in a narrower, `@smallbook' page without needing to be shortened.  Both
commands typeset in the normal font size when you format for the 8.5 by
11 inch size; indeed, in this situation, the `@smallexample' and
`@smalllisp' commands are defined to be the `@example' and `@lisp'
commands.

  In Info, the `@smallexample' and `@smalllisp' commands are equivalent
to the `@example' and `@lisp' commands, and work exactly the same.

  Mark the end of `@smallexample' or `@smalllisp' with `@end
smallexample' or `@end smalllisp', respectively.

     This is an example of text written between `@smallexample' and
     `@end smallexample'.  In Info and in an 8.5 by 11 inch manual,
     this text appears in its normal size; but in a 7 by 9.25 inch manual,
     this text appears in a smaller font.

  The `@smallexample' and `@smalllisp' commands make it easier to
prepare smaller format manuals without forcing you to edit examples by
hand to fit them onto narrower pages.

  As a general rule, a printed document looks better if you write all
the examples in a chapter consistently in `@example' or in
`@smallexample'.  Only occasionally should you mix the two formats.

  *Note Printing "Small" Books: smallbook, for more information about
the `@smallbook' command.

\1f
File: texinfo.info,  Node: display,  Next: format,  Prev: smallexample & smalllisp,  Up: Quotations and Examples

`@display'
==========

The `@display' command begins a kind of example.  It is like the
`@example' command except that, in a printed manual, `@display' does
not select the fixed-width font.  In fact, it does not specify the font
at all, so that the text appears in the same font it would have
appeared in without the `@display' command.

     This is an example of text written between an `@display' command
     and an `@end display' command.  The `@display' command
     indents the text, but does not fill it.

\1f
File: texinfo.info,  Node: format,  Next: exdent,  Prev: display,  Up: Quotations and Examples

`@format'
=========

The `@format' command is similar to `@example' except that, in the
printed manual, `@format' does not select the fixed-width font and does
not narrow the margins.

This is an example of text written between an `@format' command
and an `@end format' command.  As you can see
from this example,
the `@format' command does not fill the text.

\1f
File: texinfo.info,  Node: exdent,  Next: flushleft & flushright,  Prev: format,  Up: Quotations and Examples

`@exdent': Undoing a Line's Indentation
=======================================

The `@exdent' command removes any indentation a line might have.  The
command is written at the beginning of a line and applies only to the
text that follows the command that is on the same line.  Do not use
braces around the text.  In a printed manual, the text on an `@exdent'
line is printed in the roman font.

  `@exdent' is usually used within examples.  Thus,

     @example
     This line follows an @@example command.
     @exdent This line is exdented.
     This line follows the exdented line.
     The @@end example comes on the next line.
     @end group

produces

     This line follows an @example command.
This line is exdented.
     This line follows the exdented line.
     The @end example comes on the next line.

  In practice, the `@exdent' command is rarely used.  Usually, you
un-indent text by ending the example and returning the page to its
normal width.

\1f
File: texinfo.info,  Node: flushleft & flushright,  Next: cartouche,  Prev: exdent,  Up: Quotations and Examples

`@flushleft' and `@flushright'
==============================

The `@flushleft' and `@flushright' commands line up the ends of lines
on the left and right margins of a page, but do not fill the text.  The
commands are written on lines of their own, without braces.  The
`@flushleft' and `@flushright' commands are ended by `@end flushleft'
and `@end flushright' commands on lines of their own.

  For example,

     @flushleft
     This text is
     written flushleft.
     @end flushleft

produces

     This text is
     written flushleft.

  `@flushright' produces the type of indentation often used in the
return address of letters.  For example,

     @flushright
     Here is an example of text written
     flushright.  The @code{@flushright} command
     right justifies every line but leaves the
     left end ragged.
     @end flushright

produces

                                     Here is an example of text written
                                 flushright.  The `@flushright' command
                              right justifies every line but leaves the
                                                       left end ragged.

\1f
File: texinfo.info,  Node: cartouche,  Prev: flushleft & flushright,  Up: Quotations and Examples

Drawing Cartouches Around Examples
==================================

In a printed manual, the `@cartouche' command draws a box with rounded
corners around its contents.  You can use this command to further
highlight an example or quotation.  For instance, you could write a
manual in which one type of example is surrounded by a cartouche for
emphasis.

  The `@cartouche' command affects only the printed manual; it has no
effect in the Info file.

  For example,

     @example
     @cartouche
     % pwd
     /usr/local/share/emacs
     @end cartouche
     @end example

surrounds the two-line example with a box with rounded corners, in the
printed manual.

\1f
File: texinfo.info,  Node: Lists and Tables,  Next: Indices,  Prev: Quotations and Examples,  Up: Top

Lists and Tables
****************

Texinfo has several ways of making lists and tables.  Lists can be
bulleted or numbered; two-column tables can highlight the items in the
first column; multi-column tables are also supported.

* Menu:

* Introducing Lists::           Texinfo formats lists for you.
* itemize::                     How to construct a simple list.
* enumerate::                   How to construct a numbered list.
* Two-column Tables::           How to construct a two-column table.
* Multi-column Tables::         How to construct generalized tables.

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File: texinfo.info,  Node: Introducing Lists,  Next: itemize,  Prev: Lists and Tables,  Up: Lists and Tables

Introducing Lists
=================

  Texinfo automatically indents the text in lists or tables, and numbers
an enumerated list.  This last feature is useful if you modify the
list, since you do not need to renumber it yourself.

  Numbered lists and tables begin with the appropriate @-command at the
beginning of a line, and end with the corresponding `@end' command on a
line by itself.  The table and itemized-list commands also require that
you write formatting information on the same line as the beginning
@-command.

  Begin an enumerated list, for example, with an `@enumerate' command
and end the list with an `@end enumerate' command.  Begin an itemized
list with an `@itemize' command, followed on the same line by a
formatting command such as `@bullet', and end the list with an `@end
itemize' command.

  Precede each element of a list with an `@item' or `@itemx' command.


Here is an itemized list of the different kinds of table and lists:

   * Itemized lists with and without bullets.

   * Enumerated lists, using numbers or letters.

   * Two-column tables with highlighting.


Here is an enumerated list with the same items:

  1. Itemized lists with and without bullets.

  2. Enumerated lists, using numbers or letters.

  3. Two-column tables with highlighting.


And here is a two-column table with the same items and their @-commands:

`@itemize'
     Itemized lists with and without bullets.

`@enumerate'
     Enumerated lists, using numbers or letters.

`@table'
`@ftable'
`@vtable'
     Two-column tables with indexing.

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File: texinfo.info,  Node: itemize,  Next: enumerate,  Prev: Introducing Lists,  Up: Lists and Tables

Making an Itemized List
=======================

The `@itemize' command produces sequences of indented paragraphs, with
a bullet or other mark inside the left margin at the beginning of each
paragraph for which such a mark is desired.

  Begin an itemized list by writing `@itemize' at the beginning of a
line.  Follow the command, on the same line, with a character or a
Texinfo command that generates a mark.  Usually, you will write
`@bullet' after `@itemize', but you can use `@minus', or any character
or any special symbol that results in a single character in the Info
file.  (When you write `@bullet' or `@minus' after an `@itemize'
command, you may omit the `{}'.)

  Write the text of the indented paragraphs themselves after the
`@itemize', up to another line that says `@end itemize'.

  Before each paragraph for which a mark in the margin is desired, write
a line that says just `@item'.  Do not write any other text on this
line.

  Usually, you should put a blank line before an `@item'.  This puts a
blank line in the Info file. (TeX inserts the proper interline
whitespace in either case.)  Except when the entries are very brief,
these blank lines make the list look better.

  Here is an example of the use of `@itemize', followed by the output
it produces.  Note that `@bullet' produces a `*' in Info and a round
dot in TeX.

     @itemize @bullet
     @item
     Some text for foo.
     
     @item
     Some text
     for bar.
     @end itemize

This produces:

        * Some text for foo.

        * Some text for bar.

  Itemized lists may be embedded within other itemized lists.  Here is a
list marked with dashes embedded in a list marked with bullets:

     @itemize @bullet
     @item
     First item.
     
     @itemize @minus
     @item
     Inner item.
     
     @item
     Second inner item.
     @end itemize
     
     @item
     Second outer item.
     @end itemize

This produces:

        * First item.

             - Inner item.

             - Second inner item.

        * Second outer item.

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File: texinfo.info,  Node: enumerate,  Next: Two-column Tables,  Prev: itemize,  Up: Lists and Tables

Making a Numbered or Lettered List
==================================

`@enumerate' is like `@itemize' (*note `@itemize': itemize.), except
that the labels on the items are successive integers or letters instead
of bullets.

  Write the `@enumerate' command at the beginning of a line.  The
command does not require an argument, but accepts either a number or a
letter as an option.  Without an argument, `@enumerate' starts the list
with the number `1'.  With a numeric argument, such as `3', the command
starts the list with that number.  With an upper or lower case letter,
such as `a' or `A', the command starts the list with that letter.

  Write the text of the enumerated list in the same way you write an
itemized list: put `@item' on a line of its own before the start of
each paragraph that you want enumerated.  Do not write any other text
on the line beginning with `@item'.

  You should put a blank line between entries in the list.  This
generally makes it easier to read the Info file.

  Here is an example of `@enumerate' without an argument:

     @enumerate
     @item
     Underlying causes.
     
     @item
     Proximate causes.
     @end enumerate

This produces:

  1. Underlying causes.

  2. Proximate causes.


  Here is an example with an argument of `3':

     @enumerate 3
     @item
     Predisposing causes.
     
     @item
     Precipitating causes.
     
     @item
     Perpetuating causes.
     @end enumerate

This produces:

  3. Predisposing causes.

  4. Precipitating causes.

  5. Perpetuating causes.


  Here is a brief summary of the alternatives.  The summary is
constructed using `@enumerate' with an argument of `a'.

  a. `@enumerate'

     Without an argument, produce a numbered list, starting with the
     number 1.

  b. `@enumerate POSITIVE-INTEGER'

     With a (positive) numeric argument, start a numbered list with that
     number.  You can use this to continue a list that you interrupted
     with other text.

  c. `@enumerate UPPER-CASE-LETTER'

     With an upper case letter as argument, start a list in which each
     item is marked by a letter, beginning with that upper case letter.

  d. `@enumerate LOWER-CASE-LETTER'

     With a lower case letter as argument, start a list in which each
     item is marked by a letter, beginning with that lower case letter.

  You can also nest enumerated lists, as in an outline.

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File: texinfo.info,  Node: Two-column Tables,  Next: Multi-column Tables,  Prev: enumerate,  Up: Lists and Tables

Making a Two-column Table
=========================

`@table' is similar to `@itemize' (*note `@itemize': itemize.), but
allows you to specify a name or heading line for each item.  The
`@table' command is used to produce two-column tables, and is
especially useful for glossaries, explanatory exhibits, and
command-line option summaries.

* Menu:

* table::                       How to construct a two-column table.
* ftable vtable::               Automatic indexing for two-column tables.
* itemx::                       How to put more entries in the first column.

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File: texinfo.info,  Node: table,  Next: ftable vtable,  Prev: Two-column Tables,  Up: Two-column Tables

Using the `@table' Command
--------------------------

Use the `@table' command to produce two-column tables.

  Write the `@table' command at the beginning of a line and follow it
on the same line with an argument that is a Texinfo "indicating"
command such as `@code', `@samp', `@var', or `@kbd' (*note
Indicating::).  Although these commands are usually followed by
arguments in braces, in this case you use the command name without an
argument because `@item' will supply the argument.  This command will
be applied to the text that goes into the first column of each item and
determines how it will be highlighted.  For example, `@code' will cause
the text in the first column to be highlighted with an `@code' command.
(We recommend `@code' for `@table''s of command-line options.)

  You may also choose to use the `@asis' command as an argument to
`@table'.  `@asis' is a command that does nothing; if you use this
command after `@table', TeX and the Info formatting commands output the
first column entries without added highlighting ("as is").

  (The `@table' command may work with other commands besides those
listed here.  However, you can only use commands that normally take
arguments in braces.)

  Begin each table entry with an `@item' command at the beginning of a
line.  Write the first column text on the same line as the `@item'
command.  Write the second column text on the line following the
`@item' line and on subsequent lines.  (You do not need to type
anything for an empty second column entry.)  You may write as many
lines of supporting text as you wish, even several paragraphs.  But
only text on the same line as the `@item' will be placed in the first
column.

  Normally, you should put a blank line before an `@item' line.  This
puts a blank like in the Info file.  Except when the entries are very
brief, a blank line looks better.

  The following table, for example, highlights the text in the first
column with an `@samp' command:

     @table @samp
     @item foo
     This is the text for
     @samp{foo}.
     
     @item bar
     Text for @samp{bar}.
     @end table

This produces:

`foo'
     This is the text for `foo'.

`bar'
     Text for `bar'.

  If you want to list two or more named items with a single block of
text, use the `@itemx' command.  (*Note `@itemx': itemx.)

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File: texinfo.info,  Node: ftable vtable,  Next: itemx,  Prev: table,  Up: Two-column Tables

`@ftable' and `@vtable'
-----------------------

The `@ftable' and `@vtable' commands are the same as the `@table'
command except that `@ftable' automatically enters each of the items in
the first column of the table into the index of functions and `@vtable'
automatically enters each of the items in the first column of the table
into the index of variables.  This simplifies the task of creating
indices.  Only the items on the same line as the `@item' commands are
indexed, and they are indexed in exactly the form that they appear on
that line.  *Note Creating Indices: Indices, for more information about
indices.

  Begin a two-column table using `@ftable' or `@vtable' by writing the
@-command at the beginning of a line, followed on the same line by an
argument that is a Texinfo command such as `@code', exactly as you
would for an `@table' command; and end the table with an `@end ftable'
or `@end vtable' command on a line by itself.

  See the example for `@table' in the previous section.

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File: texinfo.info,  Node: itemx,  Prev: ftable vtable,  Up: Two-column Tables

`@itemx'
--------

Use the `@itemx' command inside a table when you have two or more first
column entries for the same item, each of which should appear on a line
of its own.  Use `@itemx' for all but the first entry; `@itemx' should
always follow an `@item' command.  The `@itemx' command works exactly
like `@item' except that it does not generate extra vertical space
above the first column text.

  For example,

     @table @code
     @item upcase
     @itemx downcase
     These two functions accept a character or a string as
     argument, and return the corresponding upper case (lower
     case) character or string.
     @end table

This produces:

`upcase'
`downcase'
     These two functions accept a character or a string as argument,
     and return the corresponding upper case (lower case) character or
     string.

(Note also that this example illustrates multi-line supporting text in
a two-column table.)

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File: texinfo.info,  Node: Multi-column Tables,  Prev: Two-column Tables,  Up: Lists and Tables

Multi-column Tables
===================

`@multitable' allows you to construct tables with any number of
columns, with each column having any width you like.

  You define the column widths on the `@multitable' line itself, and
write each row of the actual table following an `@item' command, with
columns separated by an `@tab' command.  Finally, `@end multitable'
completes the table.  Details in the sections below.

* Menu:

* Multitable Column Widths::    Defining multitable column widths.
* Multitable Rows::             Defining multitable rows, with examples.

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File: texinfo.info,  Node: Multitable Column Widths,  Next: Multitable Rows,  Prev: Multi-column Tables,  Up: Multi-column Tables

Multitable Column Widths
------------------------

You can define the column widths for a multitable in two ways: as
fractions of the line length; or with a prototype row.  Mixing the two
methods is not supported.  In either case, the widths are defined
entirely on the same line as the `@multitable' command.

  1. To specify column widths as fractions of the line length, write
     `@columnfractions' and the decimal numbers (presumably less than
     1) after the `@multitable' command, as in:

          @multitable @columnfractions .33 .33 .33

     The fractions need not add up exactly to 1.0, as these do not.
     This allows you to produce tables that do not need the full line
     length.

  2. To specify a prototype row, write the longest entry for each column
     enclosed in braces after the `@multitable' command.  For example:

          @multitable {some text for column one} {for column two}

     The first column will then have the width of the typeset `some
     text for column one', and the second column the width of `for
     column two'.

     The prototype entries need not appear in the table itself.

     Although we used simple text in this example, the prototype
     entries can contain Texinfo commands; markup commands such as
     `@code' are particularly likely to be useful.


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File: texinfo.info,  Node: Multitable Rows,  Prev: Multitable Column Widths,  Up: Multi-column Tables

Multitable Rows
---------------

After the `@multitable' command defining the column widths (see the
previous section), you begin each row in the body of a multitable with
`@item', and separate the column entries with `@tab'.  Line breaks are
not special within the table body, and you may break input lines in
your source file as necessary.

  Here is a complete example of a multi-column table (the text is from
`The XEmacs Users' Manual', *note Splitting Windows: (xemacs)Split
Window.):

     @multitable @columnfractions .15 .45 .4
     @item Key @tab Command @tab Description
     @item C-x 2
     @tab @code{split-window-vertically}
     @tab Split the selected window into two windows,
     with one above the other.
     @item C-x 3
     @tab @code{split-window-horizontally}
     @tab Split the selected window into two windows
     positioned side by side.
     @item C-Mouse-2
     @tab
     @tab In the mode line or scroll bar of a window,
     split that window.
     @end multitable

produces:

Key         Command                          Description
C-x 2       `split-window-vertically'        Split the selected window
                                             into two windows, with one
                                             above the other.
C-x 3       `split-window-horizontally'      Split the selected window
                                             into two windows positioned
                                             side by side.
C-Mouse-2                                    In the mode line or scroll
                                             bar of a window, split that
                                             window.

\1f
File: texinfo.info,  Node: Indices,  Next: Insertions,  Prev: Lists and Tables,  Up: Top

Creating Indices
****************

Using Texinfo, you can generate indices without having to sort and
collate entries manually.  In an index, the entries are listed in
alphabetical order, together with information on how to find the
discussion of each entry.  In a printed manual, this information
consists of page numbers.  In an Info file, this information is a menu
entry leading to the first node referenced.

  Texinfo provides several predefined kinds of index: an index for
functions, an index for variables, an index for concepts, and so on.
You can combine indices or use them for other than their canonical
purpose.  If you wish, you can define your own indices.

* Menu:

* Index Entries::               Choose different words for index entries.
* Predefined Indices::          Use different indices for different kinds
                                  of entry.
* Indexing Commands::           How to make an index entry.
* Combining Indices::           How to combine indices.
* New Indices::                 How to define your own indices.

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File: texinfo.info,  Node: Index Entries,  Next: Predefined Indices,  Prev: Indices,  Up: Indices

Making Index Entries
====================

When you are making index entries, it is good practice to think of the
different ways people may look for something.  Different people _do
not_ think of the same words when they look something up.  A helpful
index will have items indexed under all the different words that people
may use.  For example, one reader may think it obvious that the
two-letter names for indices should be listed under "Indices,
two-letter names", since the word "Index" is the general concept.  But
another reader may remember the specific concept of two-letter names
and search for the entry listed as "Two letter names for indices".  A
good index will have both entries and will help both readers.

  Like typesetting, the construction of an index is a highly skilled,
professional art, the subtleties of which are not appreciated until you
need to do it yourself.

  *Note Printing Indices & Menus::, for information about printing an
index at the end of a book or creating an index menu in an Info file.

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File: texinfo.info,  Node: Predefined Indices,  Next: Indexing Commands,  Prev: Index Entries,  Up: Indices

Predefined Indices
==================

Texinfo provides six predefined indices:

   * A "concept index" listing concepts that are discussed.

   * A "function index" listing functions (such as entry points of
     libraries).

   * A "variables index" listing variables (such as global variables of
     libraries).

   * A "keystroke index" listing keyboard commands.

   * A "program index" listing names of programs.

   * A "data type index" listing data types (such as structures defined
     in header files).

Not every manual needs all of these, and most manuals use two or three
of them.  This manual has two indices: a concept index and an @-command
index (that is actually the function index but is called a command
index in the chapter heading).  Two or more indices can be combined
into one using the `@synindex' or `@syncodeindex' commands.  *Note
Combining Indices::.

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File: texinfo.info,  Node: Indexing Commands,  Next: Combining Indices,  Prev: Predefined Indices,  Up: Indices

Defining the Entries of an Index
================================

The data to make an index come from many individual indexing commands
scattered throughout the Texinfo source file.  Each command says to add
one entry to a particular index; after formatting, the index will give
the current page number or node name as the reference.

  An index entry consists of an indexing command at the beginning of a
line followed, on the rest of the line, by the entry.

  For example, this section begins with the following five entries for
the concept index:

     @cindex Defining indexing entries
     @cindex Index entries
     @cindex Entries for an index
     @cindex Specifying index entries
     @cindex Creating index entries

  Each predefined index has its own indexing command--`@cindex' for the
concept index, `@findex' for the function index, and so on.

  Concept index entries consist of text.  The best way to write an index
is to choose entries that are terse yet clear.  If you can do this, the
index often looks better if the entries are not capitalized, but
written just as they would appear in the middle of a sentence.
(Capitalize proper names and acronyms that always call for upper case
letters.)  This is the case convention we use in most GNU manuals'
indices.

  If you don't see how to make an entry terse yet clear, make it longer
and clear--not terse and confusing.  If many of the entries are several
words long, the index may look better if you use a different convention:
to capitalize the first word of each entry.  But do not capitalize a
case-sensitive name such as a C or Lisp function name or a shell
command; that would be a spelling error.

  Whichever case convention you use, please use it consistently!

  Entries in indices other than the concept index are symbol names in
programming languages, or program names; these names are usually
case-sensitive, so use upper and lower case as required for them.

  By default, entries for a concept index are printed in a small roman
font and entries for the other indices are printed in a small `@code'
font.  You may change the way part of an entry is printed with the
usual Texinfo commands, such as `@file' for file names and `@emph' for
emphasis (*note Marking Text::).

  The six indexing commands for predefined indices are:

`@cindex CONCEPT'
     Make an entry in the concept index for CONCEPT.

`@findex FUNCTION'
     Make an entry in the function index for FUNCTION.

`@vindex VARIABLE'
     Make an entry in the variable index for VARIABLE.

`@kindex KEYSTROKE'
     Make an entry in the key index for KEYSTROKE.

`@pindex PROGRAM'
     Make an entry in the program index for PROGRAM.

`@tindex DATA TYPE'
     Make an entry in the data type index for DATA TYPE.

     *Caution:* Do not use a colon in an index entry.  In Info, a colon
     separates the menu entry name from the node name.  An extra colon
     confuses Info.  *Note The Parts of a Menu: Menu Parts, for more
     information about the structure of a menu entry.

  If you write several identical index entries in different places in a
Texinfo file, the index in the printed manual will list all the pages to
which those entries refer.  However, the index in the Info file will
list *only* the node that references the *first* of those index
entries.  Therefore, it is best to write indices in which each entry
refers to only one place in the Texinfo file.  Fortunately, this
constraint is a feature rather than a loss since it means that the index
will be easy to use.  Otherwise, you could create an index that lists
several pages for one entry and your reader would not know to which page
to turn.  If you have two identical entries for one topic, change the
topics slightly, or qualify them to indicate the difference.

  You are not actually required to use the predefined indices for their
canonical purposes.  For example, suppose you wish to index some C
preprocessor macros.  You could put them in the function index along
with actual functions, just by writing `@findex' commands for them;
then, when you print the "Function Index" as an unnumbered chapter, you
could give it the title `Function and Macro Index' and all will be
consistent for the reader.  Or you could put the macros in with the
data types by writing `@tindex' commands for them, and give that index
a suitable title so the reader will understand.  (*Note Printing
Indices & Menus::.)

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File: texinfo.info,  Node: Combining Indices,  Next: New Indices,  Prev: Indexing Commands,  Up: Indices

Combining Indices
=================

Sometimes you will want to combine two disparate indices such as
functions and concepts, perhaps because you have few enough of one of
them that a separate index for them would look silly.

  You could put functions into the concept index by writing `@cindex'
commands for them instead of `@findex' commands, and produce a
consistent manual by printing the concept index with the title
`Function and Concept Index' and not printing the `Function Index' at
all; but this is not a robust procedure.  It works only if your
document is never included as part of another document that is designed
to have a separate function index; if your document were to be included
with such a document, the functions from your document and those from
the other would not end up together.  Also, to make your function names
appear in the right font in the concept index, you would need to
enclose every one of them between the braces of `@code'.

* Menu:

* syncodeindex::                How to merge two indices, using `@code'
                                  font for the merged-from index.
* synindex::                    How to merge two indices, using the
                                  default font of the merged-to index.

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File: texinfo.info,  Node: syncodeindex,  Next: synindex,  Prev: Combining Indices,  Up: Combining Indices

`@syncodeindex'
---------------

When you want to combine functions and concepts into one index, you
should index the functions with `@findex' and index the concepts with
`@cindex', and use the `@syncodeindex' command to redirect the function
index entries into the concept index.

  The `@syncodeindex' command takes two arguments; they are the name of
the index to redirect, and the name of the index to redirect it to.
The template looks like this:

     @syncodeindex FROM TO

  For this purpose, the indices are given two-letter names:

`cp'
     concept index

`fn'
     function index

`vr'
     variable index

`ky'
     key index

`pg'
     program index

`tp'
     data type index

  Write an `@syncodeindex' command before or shortly after the
end-of-header line at the beginning of a Texinfo file.  For example, to
merge a function index with a concept index, write the following:

     @syncodeindex fn cp

This will cause all entries designated for the function index to merge
in with the concept index instead.

  To merge both a variables index and a function index into a concept
index, write the following:

     @syncodeindex vr cp
     @syncodeindex fn cp

  The `@syncodeindex' command puts all the entries from the `from'
index (the redirected index) into the `@code' font, overriding whatever
default font is used by the index to which the entries are now
directed.  This way, if you direct function names from a function index
into a concept index, all the function names are printed in the `@code'
font as you would expect.

\1f
File: texinfo.info,  Node: synindex,  Prev: syncodeindex,  Up: Combining Indices

`@synindex'
-----------

The `@synindex' command is nearly the same as the `@syncodeindex'
command, except that it does not put the `from' index  entries into the
`@code' font; rather it puts them in the roman font.  Thus, you use
`@synindex' when you merge a concept index into a function index.

  *Note Printing Indices & Menus::, for information about printing an
index at the end of a book or creating an index menu in an Info file.

\1f
File: texinfo.info,  Node: New Indices,  Prev: Combining Indices,  Up: Indices

Defining New Indices
====================

In addition to the predefined indices, you may use the `@defindex' and
`@defcodeindex' commands to define new indices.  These commands create
new indexing @-commands with which you mark index entries.  The
`@defindex 'command is used like this:

     @defindex NAME

  The name of an index should be a two letter word, such as `au'.  For
example:

     @defindex au

  This defines a new index, called the `au' index.  At the same time,
it creates a new indexing command, `@auindex', that you can use to make
index entries.  Use the new indexing command just as you would use a
predefined indexing command.

  For example, here is a section heading followed by a concept index
entry and two `au' index entries.

     @section Cognitive Semantics
     @cindex kinesthetic image schemas
     @auindex Johnson, Mark
     @auindex Lakoff, George

(Evidently, `au' serves here as an abbreviation for "author".)  Texinfo
constructs the new indexing command by concatenating the name of the
index with `index'; thus, defining an `au' index leads to the automatic
creation of an `@auindex' command.

  Use the `@printindex' command to print the index, as you do with the
predefined indices.  For example:

     @node Author Index, Subject Index, , Top
     @unnumbered Author Index
     
     @printindex au

  The `@defcodeindex' is like the `@defindex' command, except that, in
the printed output, it prints entries in an `@code' font instead of a
roman font.  Thus, it parallels the `@findex' command rather than the
`@cindex' command.

  You should define new indices within or right after the end-of-header
line of a Texinfo file, before any `@synindex' or `@syncodeindex'
commands (*note Header::).

\1f
File: texinfo.info,  Node: Insertions,  Next: Breaks,  Prev: Indices,  Up: Top

Special Insertions
******************

Texinfo provides several commands for inserting characters that have
special meaning in Texinfo, such as braces, and for other graphic
elements that do not correspond to simple characters you can type.

* Menu:

* Braces Atsigns::              How to insert braces, `@'.
* Inserting Space::             How to insert the right amount of space
                                  within a sentence.
* Inserting Accents::           How to insert accents and special characters.
* Dots Bullets::                How to insert dots and bullets.
* TeX and copyright::           How to insert the TeX logo
                                  and the copyright symbol.
* pounds::                      How to insert the pounds currency symbol.
* minus::                       How to insert a minus sign.
* math::                        How to format a mathematical expression.
* Glyphs::                      How to indicate results of evaluation,
                                  expansion of macros, errors, etc.
* Images::                      How to include graphics.

\1f
File: texinfo.info,  Node: Braces Atsigns,  Next: Inserting Space,  Prev: Insertions,  Up: Insertions

Inserting @ and Braces
======================

`@' and curly braces are special characters in Texinfo.  To insert
these characters so they appear in text, you must put an `@' in front
of these characters to prevent Texinfo from misinterpreting them.

  Do not put braces after any of these commands; they are not necessary.

* Menu:

* Inserting An Atsign::         How to insert `@'.
* Inserting Braces::            How to insert `{' and `}'.

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File: texinfo.info,  Node: Inserting An Atsign,  Next: Inserting Braces,  Prev: Braces Atsigns,  Up: Braces Atsigns

Inserting `@' with @@
---------------------

`@@' stands for a single `@' in either printed or Info output.

  Do not put braces after an `@@' command.

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File: texinfo.info,  Node: Inserting Braces,  Prev: Inserting An Atsign,  Up: Braces Atsigns

Inserting `{' and `}'with @{ and @}
-----------------------------------

`@{' stands for a single `{' in either printed or Info output.

  `@}' stands for a single `}' in either printed or Info output.

  Do not put braces after either an `@{' or an `@}' command.

\1f
File: texinfo.info,  Node: Inserting Space,  Next: Inserting Accents,  Prev: Braces Atsigns,  Up: Insertions

Inserting Space
===============

The following sections describe commands that control spacing of various
kinds within and after sentences.

* Menu:

* Not Ending a Sentence::       Sometimes a . doesn't end a sentence.
* Ending a Sentence::           Sometimes it does.
* Multiple Spaces::             Inserting multiple spaces.
* dmn::                         How to format a dimension.

\1f
File: texinfo.info,  Node: Not Ending a Sentence,  Next: Ending a Sentence,  Prev: Inserting Space,  Up: Inserting Space

Not Ending a Sentence
---------------------

Depending on whether a period or exclamation point or question mark is
inside or at the end of a sentence, less or more space is inserted after
a period in a typeset manual.  Since it is not always possible for
Texinfo to determine when a period ends a sentence and when it is used
in an abbreviation, special commands are needed in some circumstances.
(Usually, Texinfo can guess how to handle periods, so you do not need to
use the special commands; you just enter a period as you would if you
were using a typewriter, which means you put two spaces after the
period, question mark, or exclamation mark that ends a sentence.)

  Use the `@:' command after a period, question mark, exclamation mark,
or colon that should not be followed by extra space.  For example, use
`@:' after periods that end abbreviations which are not at the ends of
sentences.

  For example,

     The s.o.p.@: has three parts ...
     The s.o.p. has three parts ...

produces

     The s.o.p. has three parts ...
     The s.o.p. has three parts ...

(Incidentally, `s.o.p.' is an abbreviation for "Standard Operating
Procedure".)

  `@:' has no effect on the Info output.  Do not put braces after `@:'.

\1f
File: texinfo.info,  Node: Ending a Sentence,  Next: Multiple Spaces,  Prev: Not Ending a Sentence,  Up: Inserting Space

Ending a Sentence
-----------------

Use `@.' instead of a period, `@!' instead of an exclamation point, and
`@?' instead of a question mark at the end of a sentence that ends with
a single capital letter.  Otherwise, TeX will think the letter is an
abbreviation and will not insert the correct end-of-sentence spacing.
Here is an example:

     Give it to M.I.B. and to M.E.W@.  Also, give it to R.J.C@.
     Give it to M.I.B. and to M.E.W.  Also, give it to R.J.C.

produces

     Give it to M.I.B. and to M.E.W.  Also, give it to R.J.C.
     Give it to M.I.B. and to M.E.W.  Also, give it to R.J.C.

  In the Info file output, `@.' is equivalent to a simple `.'; likewise
for `@!' and `@?'.

  The meanings of `@:' and `@.' in Texinfo are designed to work well
with the Emacs sentence motion commands (*note Sentences:
(xemacs)Sentences.).  This made it necessary for them to be
incompatible with some other formatting systems that use @-commands.

  Do not put braces after any of these commands.

\1f
File: texinfo.info,  Node: Multiple Spaces,  Next: dmn,  Prev: Ending a Sentence,  Up: Inserting Space

Multiple Spaces
---------------

Ordinarily, TeX collapses multiple whitespace characters (space, tab,
and newline) into a single space.  Info output, on the other hand,
preserves whitespace as you type it, except for changing a newline into
a space; this is why it is important to put two spaces at the end of
sentences in Texinfo documents.

  Occasionally, you may want to actually insert several consecutive
spaces, either for purposes of example (what your program does with
multiple spaces as input), or merely for purposes of appearance in
headings or lists.  Texinfo supports three commands: `@SPACE', `@TAB',
and `@NL', all of which insert a single space into the output.  (Here,
`@SPACE' represents an `@' character followed by a space, i.e., `@ ',
and `TAB' and `NL' represent the tab character and end-of-line, i.e.,
when `@' is the last character on a line.)

  For example,
     Spacey@ @ @ @
     example.

produces

     Spacey    example.

  Other possible uses of `@SPACE' have been subsumed by `@multitable'
(*note Multi-column Tables::).

  Do not follow any of these commands with braces.

\1f
File: texinfo.info,  Node: dmn,  Prev: Multiple Spaces,  Up: Inserting Space

`@dmn'{DIMENSION}: Format a Dimension
-------------------------------------

At times, you may want to write `12pt' or `8.5in' with little or no
space between the number and the abbreviation for the dimension.  You
can use the `@dmn' command to do this.  On seeing the command, TeX
inserts just enough space for proper typesetting; the Info formatting
commands insert no space at all, since the Info file does not require
it.

  To use the `@dmn' command, write the number and then follow it
immediately, with no intervening space, by `@dmn', and then by the
dimension within braces.  For example,

     A4 paper is 8.27@dmn{in} wide.

produces

     A4 paper is 8.27in wide.

  Not everyone uses this style.  Some people prefer `8.27 in.@:' or
`8.27 inches' to `8.27@dmn{in}' in the Texinfo file.  In these cases,
however, the formatters may insert a line break between the number and
the dimension, so use `@w' (*note w::).  Also, if you write a period
after an abbreviation within a sentence, you should write `@:' after
the period to prevent TeX from inserting extra whitespace, as shown
here.  *Note Inserting Space::.

\1f
File: texinfo.info,  Node: Inserting Accents,  Next: Dots Bullets,  Prev: Inserting Space,  Up: Insertions

Inserting Accents
=================

Here is a table with the commands Texinfo provides for inserting
floating accents.  The commands with non-alphabetic names do not take
braces around their argument (which is taken to be the next character).
(Exception: `@,' _does_ take braces around its argument.)  This is so
as to make the source as convenient to type and read as possible, since
accented characters are very common in some languages.

Command           Output   What
@"o               o"       umlaut accent
@'o               o'       acute accent
@,{c}             c,       cedilla accent
@=o               o=       macron/overbar accent
@^o               o^       circumflex accent
@`o               o`       grave accent
@~o               o~       tilde accent
@dotaccent{o}     o.       overdot accent
@H{o}             o''      long Hungarian umlaut
@ringaccent{o}    o*       ring accent
@tieaccent{oo}    oo[      tie-after accent
@u{o}             o(       breve accent
@ubaraccent{o}    o_       underbar accent
@udotaccent{o}    .o       underdot accent
@v{o}             o<       hacek or check accent

  This table lists the Texinfo commands for inserting other characters
commonly used in languages other than English.

@exclamdown{}     !       upside-down !
@questiondown{}   ?       upside-down ?
@aa{},@AA{}       aa,AA   A,a with circle
@ae{},@AE{}       ae,AE   ae,AE ligatures
@dotless{i}       i       dotless i
@dotless{j}       j       dotless j
@l{},@L{}         /l,/L   suppressed-L,l
@o{},@O{}         /o,/O   O,o with slash
@oe{},@OE{}       oe,OE   OE,oe ligatures
@ss{}             ss      es-zet or sharp S

\1f
File: texinfo.info,  Node: Dots Bullets,  Next: TeX and copyright,  Prev: Inserting Accents,  Up: Insertions

Inserting Ellipsis, Dots, and Bullets
=====================================

An "ellipsis" (a line of dots) is not typeset as a string of periods,
so a special command is used for ellipsis in Texinfo.  The `@bullet'
command is special, too.  Each of these commands is followed by a pair
of braces, `{}', without any whitespace between the name of the command
and the braces.  (You need to use braces with these commands because
you can use them next to other text; without the braces, the formatters
would be confused.  *Note @-Command Syntax: Command Syntax, for further
information.)

* Menu:

* dots::                        How to insert dots ...
* bullet::                      How to insert a bullet.

\1f
File: texinfo.info,  Node: dots,  Next: bullet,  Prev: Dots Bullets,  Up: Dots Bullets

`@dots'{} (...)
---------------

Use the `@dots{}' command to generate an ellipsis, which is three dots
in a row, appropriately spaced, like this: `...'.  Do not simply write
three periods in the input file; that would work for the Info file
output, but would produce the wrong amount of space between the periods
in the printed manual.

  Similarly, the `@enddots{}' command generates an end-of-sentence
ellipsis (four dots) ....

\1f
File: texinfo.info,  Node: bullet,  Prev: dots,  Up: Dots Bullets

`@bullet'{} (*)
---------------

Use the `@bullet{}' command to generate a large round dot, or the
closest possible thing to one.  In Info, an asterisk is used.

  Here is a bullet: *

  When you use `@bullet' in `@itemize', you do not need to type the
braces, because `@itemize' supplies them.  (*Note `@itemize': itemize.)

\1f
File: texinfo.info,  Node: TeX and copyright,  Next: pounds,  Prev: Dots Bullets,  Up: Insertions

Inserting TeX and the Copyright Symbol
======================================

The logo `TeX' is typeset in a special fashion and it needs an
@-command.  The copyright symbol, `(C)', is also special.  Each of
these commands is followed by a pair of braces, `{}', without any
whitespace between the name of the command and the braces.

* Menu:

* tex::                         How to insert the TeX logo.
* copyright symbol::            How to use `@copyright'{}.

\1f
File: texinfo.info,  Node: tex,  Next: copyright symbol,  Prev: TeX and copyright,  Up: TeX and copyright

`@TeX'{} (TeX)
--------------

Use the `@TeX{}' command to generate `TeX'.  In a printed manual, this
is a special logo that is different from three ordinary letters.  In
Info, it just looks like `TeX'.  The `@TeX{}' command is unique among
Texinfo commands in that the `T' and the `X' are in upper case.

\1f
File: texinfo.info,  Node: copyright symbol,  Prev: tex,  Up: TeX and copyright

`@copyright'{} ((C))
--------------------

Use the `@copyright{}' command to generate `(C)'.  In a printed manual,
this is a `c' inside a circle, and in Info, this is `(C)'.

\1f
File: texinfo.info,  Node: pounds,  Next: minus,  Prev: TeX and copyright,  Up: Insertions

`@pounds{}' (#): Pounds Sterling
================================

Use the `@pounds{}' command to generate `#'.  In a printed manual, this
is the symbol for the currency pounds sterling.  In Info, it is a `#'.
Other currency symbols are unfortunately not available.

\1f
File: texinfo.info,  Node: minus,  Next: math,  Prev: pounds,  Up: Insertions

`@minus'{} (-): Inserting a Minus Sign
======================================

Use the `@minus{}' command to generate a minus sign.  In a fixed-width
font, this is a single hyphen, but in a proportional font, the symbol
is the customary length for a minus sign--a little longer than a
hyphen, shorter than an em-dash:

     `-' is a minus sign generated with `@minus{}',
     
     `-' is a hyphen generated with the character `-',
     
     `---' is an em-dash for text.

In the fixed-width font used by Info, `@minus{}' is the same as a
hyphen.

  You should not use `@minus{}' inside `@code' or `@example' because
the width distinction is not made in the fixed-width font they use.

  When you use `@minus' to specify the mark beginning each entry in an
itemized list, you do not need to type the braces (*note `@itemize':
itemize..)

\1f
File: texinfo.info,  Node: math,  Next: Glyphs,  Prev: minus,  Up: Insertions

`@math' - Inserting Mathematical Expressions
============================================

You can write a short mathematical expression with the `@math' command.
Write the mathematical expression between braces, like this:

     @math{(a + b)(a + b) = a^2 + 2ab + b^2}

This produces the following in Info:

     (a + b)(a + b) = a^2 + 2ab + b^2

  Thus, the `@math' command has no effect on the Info output.

  For complex mathematical expressions, you can also use TeX directly
(*note Raw Formatter Commands::).  When you use TeX directly, remember
to write the mathematical expression between one or two `$'
(dollar-signs) as appropriate.

\1f
File: texinfo.info,  Node: Glyphs,  Next: Images,  Prev: math,  Up: Insertions

Glyphs for Examples
===================

In Texinfo, code is often illustrated in examples that are delimited by
`@example' and `@end example', or by `@lisp' and `@end lisp'.  In such
examples, you can indicate the results of evaluation or an expansion
using `=>' or `==>'.  Likewise, there are commands to insert glyphs to
indicate printed output, error messages, equivalence of expressions,
and the location of point.

  The glyph-insertion commands do not need to be used within an
example, but most often they are.  Every  glyph-insertion command is
followed by a pair of left- and right-hand braces.

* Menu:

* Glyphs Summary::
* result::                      How to show the result of expression.
* expansion::                   How to indicate an expansion.
* Print Glyph::                 How to indicate printed output.
* Error Glyph::                 How to indicate an error message.
* Equivalence::                 How to indicate equivalence.
* Point Glyph::                 How to indicate the location of point.

\1f
File: texinfo.info,  Node: Glyphs Summary,  Next: result,  Prev: Glyphs,  Up: Glyphs

Glyphs Summary
--------------

Here are the different glyph commands:

=>
     `@result{}' points to the result of an expression.

==>
     `@expansion{}' shows the results of a macro expansion.

-|
     `@print{}' indicates printed output.

error-->
     `@error{}' indicates that the following text is an error message.

==
     `@equiv{}' indicates the exact equivalence of two forms.

-!-
     `@point{}' shows the location of point.

* Menu:

* result::
* expansion::
* Print Glyph::
* Error Glyph::
* Equivalence::
* Point Glyph::

\1f
File: texinfo.info,  Node: result,  Next: expansion,  Prev: Glyphs Summary,  Up: Glyphs

`@result{}' (=>): Indicating Evaluation
---------------------------------------

Use the `@result{}' command to indicate the result of evaluating an
expression.

  The `@result{}' command is displayed as `=>' in Info and as a double
stemmed arrow in the printed output.

  Thus, the following,

     (cdr '(1 2 3))
          => (2 3)

may be read as "`(cdr '(1 2 3))' evaluates to `(2 3)'".

\1f
File: texinfo.info,  Node: expansion,  Next: Print Glyph,  Prev: result,  Up: Glyphs

`@expansion{}' (==>): Indicating an Expansion
---------------------------------------------

When an expression is a macro call, it expands into a new expression.
You can indicate the result of the expansion with the `@expansion{}'
command.

  The `@expansion{}' command is displayed as `==>' in Info and as a
long arrow with a flat base in the printed output.

  For example, the following

     @lisp
     (third '(a b c))
          @expansion{} (car (cdr (cdr '(a b c))))
          @result{} c
     @end lisp

produces

     (third '(a b c))
          ==> (car (cdr (cdr '(a b c))))
          => c

which may be read as:

     `(third '(a b c))' expands to `(car (cdr (cdr '(a b c))))'; the
     result of evaluating the expression is `c'.

Often, as in this case, an example looks better if the `@expansion{}'
and `@result{}' commands are indented five spaces.

\1f
File: texinfo.info,  Node: Print Glyph,  Next: Error Glyph,  Prev: expansion,  Up: Glyphs

`@print{}' (-|): Indicating Printed Output
------------------------------------------

Sometimes an expression will print output during its execution.  You
can indicate the printed output with the `@print{}' command.

  The `@print{}' command is displayed as `-|' in Info and similarly, as
a horizontal dash butting against a vertical bar, in the printed output.

  In the following example, the printed text is indicated with `-|',
and the value of the expression follows on the last line.

     (progn (print 'foo) (print 'bar))
          -| foo
          -| bar
          => bar

In a Texinfo source file, this example is written as follows:

     @lisp
     (progn (print 'foo) (print 'bar))
          @print{} foo
          @print{} bar
          @result{} bar
     @end lisp

\1f
File: texinfo.info,  Node: Error Glyph,  Next: Equivalence,  Prev: Print Glyph,  Up: Glyphs

`@error{}' (error-->): Indicating an Error Message
--------------------------------------------------

A piece of code may cause an error when you evaluate it.  You can
designate the error message with the `@error{}' command.

  The `@error{}' command is displayed as `error-->' in Info and as the
word `error' in a box in the printed output.

  Thus,

     @lisp
     (+ 23 'x)
     @error{} Wrong type argument: integer-or-marker-p, x
     @end lisp

produces

     (+ 23 'x)
     error--> Wrong type argument: integer-or-marker-p, x

This indicates that the following error message is printed when you
evaluate the expression:

     Wrong type argument: integer-or-marker-p, x

  `error-->' itself is not part of the error message.

\1f
File: texinfo.info,  Node: Equivalence,  Next: Point Glyph,  Prev: Error Glyph,  Up: Glyphs

`@equiv{}' (==): Indicating Equivalence
---------------------------------------

Sometimes two expressions produce identical results.  You can indicate
the exact equivalence of two forms with the `@equiv{}' command.

  The `@equiv{}' command is displayed as `==' in Info and as a three
parallel horizontal lines in the printed output.

  Thus,

     @lisp
     (make-sparse-keymap) @equiv{} (list 'keymap)
     @end lisp

produces

     (make-sparse-keymap) == (list 'keymap)

This indicates that evaluating `(make-sparse-keymap)' produces
identical results to evaluating `(list 'keymap)'.

\1f
File: texinfo.info,  Node: Point Glyph,  Prev: Equivalence,  Up: Glyphs

`@point{}' (-!-): Indicating Point in a Buffer
----------------------------------------------

Sometimes you need to show an example of text in an Emacs buffer.  In
such examples, the convention is to include the entire contents of the
buffer in question between two lines of dashes containing the buffer
name.

  You can use the `@point{}' command to show the location of point in
the text in the buffer.  (The symbol for point, of course, is not part
of the text in the buffer; it indicates the place _between_ two
characters where point is located.)

  The `@point{}' command is displayed as `-!-' in Info and as a small
five pointed star in the printed output.

  The following example shows the contents of buffer `foo' before and
after evaluating a Lisp command to insert the word `changed'.

     ---------- Buffer: foo ----------
     This is the -!-contents of foo.
     ---------- Buffer: foo ----------

     (insert "changed ")
          => nil
     ---------- Buffer: foo ----------
     This is the changed -!-contents of foo.
     ---------- Buffer: foo ----------

  In a Texinfo source file, the example is written like this:

     @example
     ---------- Buffer: foo ----------
     This is the @point{}contents of foo.
     ---------- Buffer: foo ----------
     
     (insert "changed ")
          @result{} nil
     ---------- Buffer: foo ----------
     This is the changed @point{}contents of foo.
     ---------- Buffer: foo ----------
     @end example

\1f
File: texinfo.info,  Node: Images,  Prev: Glyphs,  Up: Insertions

Inserting Images
================

You can insert an image in an external file with the `@image' command:

     @image{FILENAME, [WIDTH], [HEIGHT]}

  The FILENAME argument is mandatory, and must not have an extension,
because the different processors support different formats: TeX reads
the file `FILENAME.eps' (Encapsulated PostScript format); `makeinfo'
uses `FILENAME.txt' verbatim for Info output (more or less as if it was
an `@example').  HTML output requires `FILENAME.jpg'.

  The optional WIDTH and HEIGHT arguments specify the size to scale the
image to (they are ignored for Info output).  If they are both
specified, the image is presented in its natural size (given in the
file); if only one is specified, the other is scaled proportionately;
and if both are specified, both are respected, thus possibly distorting
the original image by changing its aspect ratio.

  The WIDTH and HEIGHT may be specified using any valid TeX dimension,
namely:

pt
     point (72.27pt = 1in)

pc
     pica (1pc = 12pt)

bp
     big point (72bp = 1in)

in
     inch

cm
     centimeter (2.54cm = 1in)

mm
     millimeter (10mm = 1cm)

dd
     dido^t point (1157dd = 1238pt)

cc
     cicero (1cc = 12dd)

sp
     scaled point (65536sp = 1pt)

  For example, the following will scale a file `ridt.eps' to one inch
vertically, with the width scaled proportionately:

     @image{ridt,,1in}

  For `@image' to work with TeX, the file `epsf.tex' must be installed
somewhere that TeX can find it.  This file is included in the Texinfo
distribution and is available from `ftp://ftp.tug.org/tex/epsf.tex'.

\1f
File: texinfo.info,  Node: Breaks,  Next: Definition Commands,  Prev: Insertions,  Up: Top

Making and Preventing Breaks
****************************

Usually, a Texinfo file is processed both by TeX and by one of the Info
formatting commands.  Line, paragraph, or page breaks sometimes occur
in the `wrong' place in one or other form of output.  You must ensure
that text looks right both in the printed manual and in the Info file.

  For example, in a printed manual, page breaks may occur awkwardly in
the middle of an example; to prevent this, you can hold text together
using a grouping command that keeps the text from being split across
two pages.  Conversely, you may want to force a page break where none
would occur normally.  Fortunately, problems like these do not often
arise.  When they do, use the break, break prevention, or pagination
commands.

* Menu:

* Break Commands::              Cause and prevent splits.
* Line Breaks::                 How to force a single line to use two lines.
* - and hyphenation::           How to tell TeX about hyphenation points.
* w::                           How to prevent unwanted line breaks.
* sp::                          How to insert blank lines.
* page::                        How to force the start of a new page.
* group::                       How to prevent unwanted page breaks.
* need::                        Another way to prevent unwanted page breaks.

\1f
File: texinfo.info,  Node: Break Commands,  Next: Line Breaks,  Prev: Breaks,  Up: Breaks

The Break Commands
==================

  The break commands create or allow line and paragraph breaks:

`@*'
     Force a line break.

`@sp N'
     Skip N blank lines.

`@-'
     Insert a discretionary hyphen.

`@hyphenation{HY-PHEN-A-TED WORDS}'
     Define hyphen points in HY-PHEN-A-TED WORDS.

  The line-break-prevention command holds text together all on one line:

`@w{TEXT}'
     Prevent TEXT from being split and hyphenated across two lines.

  The pagination commands apply only to printed output, since Info
files do not have pages.

`@page'
     Start a new page in the printed manual.

`@group'
     Hold text together that must appear on one printed page.

`@need MILS'
     Start a new printed page if not enough space on this one.

\1f
File: texinfo.info,  Node: Line Breaks,  Next: - and hyphenation,  Prev: Break Commands,  Up: Breaks

`@*': Generate Line Breaks
==========================

The `@*' command forces a line break in both the printed manual and in
Info.

  For example,

     This line @* is broken @*in two places.

produces

     This line
      is broken
     in two places.

(Note that the space after the first `@*' command is faithfully carried
down to the next line.)

  The `@*' command is often used in a file's copyright page:

     This is edition 2.0 of the Texinfo documentation,@*
     and is for ...

In this case, the `@*' command keeps TeX from stretching the line
across the whole page in an ugly manner.

     *Please note:* Do not write braces after an `@*' command; they are
     not needed.

     Do not write an `@refill' command at the end of a paragraph
     containing an `@*' command; it will cause the paragraph to be
     refilled after the line break occurs, negating the effect of the
     line break.

\1f
File: texinfo.info,  Node: - and hyphenation,  Next: w,  Prev: Line Breaks,  Up: Breaks

`@-' and `@hyphenation': Helping TeX hyphenate
==============================================

Although TeX's hyphenation algorithm is generally pretty good, it does
miss useful hyphenation points from time to time.  (Or, far more
rarely, insert an incorrect hyphenation.)  So, for documents with an
unusual vocabulary or when fine-tuning for a printed edition, you may
wish to help TeX out.  Texinfo supports two commands for this:

`@-'
     Insert a discretionary hyphen, i.e., a place where TeX can (but
     does not have to) hyphenate.  This is especially useful when you
     notice an overfull hbox is due to TeX missing a hyphenation (*note
     Overfull hboxes::).  TeX will not insert any hyphenation points in
     a word containing `@-'.

`@hyphenation{HY-PHEN-A-TED WORDS}'
     Tell TeX how to hyphenate HY-PHEN-A-TED WORDS.  As shown, you put
     a `-' at each hyphenation point.  For example:
          @hyphenation{man-u-script man-u-scripts}

     TeX only uses the specified hyphenation points when the words
     match exactly, so give all necessary variants.

  Info output is not hyphenated, so these commands have no effect there.

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`@w'{TEXT}: Prevent Line Breaks
===============================

`@w{TEXT}' outputs TEXT and prohibits line breaks within TEXT.

  You can use the `@w' command to prevent TeX from automatically
hyphenating a long name or phrase that happens to fall near the end of a
line.

     You can copy GNU software from @w{@samp{ftp.gnu.ai.mit.edu}}.

produces

     You can copy GNU software from `ftp.gnu.ai.mit.edu'.

     *Caution:* Do not write an `@refill' command at the end of a
     paragraph containing an `@w' command; it will cause the paragraph
     to be refilled and may thereby negate the effect of the `@w'
     command.

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`@sp' N: Insert Blank Lines
===========================

A line beginning with and containing only `@sp N' generates N blank
lines of space in both the printed manual and the Info file.  `@sp'
also forces a paragraph break.  For example,

     @sp 2

generates two blank lines.

  The `@sp' command is most often used in the title page.

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`@page': Start a New Page
=========================

A line containing only `@page' starts a new page in a printed manual.
The command has no effect on Info files since they are not paginated.
An `@page' command is often used in the `@titlepage' section of a
Texinfo file to start the copyright page.

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`@group': Prevent Page Breaks
=============================

The `@group' command (on a line by itself) is used inside an `@example'
or similar construct to begin an unsplittable vertical group, which
will appear entirely on one page in the printed output.  The group is
terminated by a line containing only `@end group'.  These two lines
produce no output of their own, and in the Info file output they have
no effect at all.

  Although `@group' would make sense conceptually in a wide variety of
contexts, its current implementation works reliably only within
`@example' and variants, and within `@display', `@format', `@flushleft'
and `@flushright'.  *Note Quotations and Examples::.  (What all these
commands have in common is that each line of input produces a line of
output.)  In other contexts, `@group' can cause anomalous vertical
spacing.

  This formatting requirement means that you should write:

     @example
     @group
     ...
     @end group
     @end example

with the `@group' and `@end group' commands inside the `@example' and
`@end example' commands.

  The `@group' command is most often used to hold an example together
on one page.  In this Texinfo manual, more than 100 examples contain
text that is enclosed between `@group' and `@end group'.

  If you forget to end a group, you may get strange and unfathomable
error messages when you run TeX.  This is because TeX keeps trying to
put the rest of the Texinfo file onto the one page and does not start
to generate error messages until it has processed considerable text.
It is a good rule of thumb to look for a missing `@end group' if you
get incomprehensible error messages in TeX.

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`@need MILS': Prevent Page Breaks
=================================

A line containing only `@need N' starts a new page in a printed manual
if fewer than N mils (thousandths of an inch) remain on the current
page.  Do not use braces around the argument N.  The `@need' command
has no effect on Info files since they are not paginated.

  This paragraph is preceded by an `@need' command that tells TeX to
start a new page if fewer than 800 mils (eight-tenths inch) remain on
the page.  It looks like this:

     @need 800
     This paragraph is preceded by ...

  The `@need' command is useful for preventing orphans (single lines at
the bottoms of printed pages).

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File: texinfo.info,  Node: Definition Commands,  Next: Footnotes,  Prev: Breaks,  Up: Top

Definition Commands
*******************

The `@deffn' command and the other "definition commands" enable you to
describe functions, variables, macros, commands, user options, special
forms and other such artifacts in a uniform format.

  In the Info file, a definition causes the entity
category--`Function', `Variable', or whatever--to appear at the
beginning of the first line of the definition, followed by the entity's
name and arguments.  In the printed manual, the command causes TeX to
print the entity's name and its arguments on the left margin and print
the category next to the right margin.  In both output formats, the
body of the definition is indented.  Also, the name of the entity is
entered into the appropriate index: `@deffn' enters the name into the
index of functions, `@defvr' enters it into the index of variables, and
so on.

  A manual need not and should not contain more than one definition for
a given name.  An appendix containing a summary should use `@table'
rather than the definition commands.

* Menu:

* Def Cmd Template::            How to structure a description using a
                                  definition command.
* Optional Arguments::          How to handle optional and repeated arguments.
* deffnx::                      How to group two or more `first' lines.
* Def Cmds in Detail::          All the definition commands.
* Def Cmd Conventions::         Conventions for writing definitions.
* Sample Function Definition::

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The Template for a Definition
=============================

The `@deffn' command is used for definitions of entities that resemble
functions.  To write a definition using the `@deffn' command, write the
`@deffn' command at the beginning of a line and follow it on the same
line by the category of the entity, the name of the entity itself, and
its arguments (if any).  Then write the body of the definition on
succeeding lines.  (You may embed examples in the body.)  Finally, end
the definition with an `@end deffn' command written on a line of its
own.  (The other definition commands follow the same format.)

  The template for a definition looks like this:

     @deffn CATEGORY NAME ARGUMENTS...
     BODY-OF-DEFINITION
     @end deffn

For example,

     @deffn Command forward-word count
     This command moves point forward @var{count} words
     (or backward if @var{count} is negative). ...
     @end deffn

produces

      - Command: forward-word count
          This function moves point forward COUNT words (or backward if
          COUNT is negative). ...

  Capitalize the category name like a title.  If the name of the
category contains spaces, as in the phrase `Interactive Command', write
braces around it.  For example:

     @deffn {Interactive Command} isearch-forward
     ...
     @end deffn

Otherwise, the second word will be mistaken for the name of the entity.

  Some of the definition commands are more general than others.  The
`@deffn' command, for example, is the general definition command for
functions and the like--for entities that may take arguments.  When you
use this command, you specify the category to which the entity belongs.
The `@deffn' command possesses three predefined, specialized
variations, `@defun', `@defmac', and `@defspec', that specify the
category for you: "Function", "Macro", and "Special Form" respectively.
(In Lisp, a special form is an entity much like a function.)  The
`@defvr' command also is accompanied by several predefined, specialized
variations for describing particular kinds of variables.

  The template for a specialized definition, such as `@defun', is
similar to the template for a generalized definition, except that you
do not need to specify the category:

     @defun NAME ARGUMENTS...
     BODY-OF-DEFINITION
     @end defun

Thus,

     @defun buffer-end flag
     This function returns @code{(point-min)} if @var{flag}
     is less than 1, @code{(point-max)} otherwise.
     ...
     @end defun

produces

      - Function: buffer-end flag
          This function returns `(point-min)' if FLAG is less than 1,
          `(point-max)' otherwise.  ...

*Note Sample Function Definition: Sample Function Definition, for a
more detailed example of a function definition, including the use of
`@example' inside the definition.

  The other specialized commands work like `@defun'.