This manual describes how to install and use graphviz-dot-mode, an Emacs package for working with Graphviz DOT-format files.

Copyright © 2017 Daniel Birket.

Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.3 or any later version published by the Free Software Foundation; with no Invariant Sections, with no Front-Cover Texts, and with no Back-Cover Texts. A copy of the license is included in the section entitled GNU Free Documentation License.

This is the graphviz-dot-mode Manual, edition 0.3.10.a, by Daniel Birket, updated November 20, 2017, which describes how to install and use the Emacs package graphviz-dot-mode, version 0.3.10, released 25 May 2015, which was written by and Copyright © 2002-2015 Pieter Pareit, et al. (See http://ppareit.github.io/graphviz-dot-mode/)

This document was composed using Emacs v25.2.1 (Richard M. Stallman, et al. See https://www.gnu.org/software/emacs/) and compiled from .texi source with GNU Texinfo v6.4 (Richard M. Stallman, et al. See https://www.gnu.org/software/texinfo/) to docbook format (OASIS See http://docbook.org, then converted to this format using Pandoc v1.19.2.1 (John MacFarlane, et al. http://pandoc.org) This format has no index. Graphviz is by AT&T Labs Research. (See http://graphviz.org)

This manual is based upon the comments and doc strings in the graphviz-dot-mode.el source code, which begins with:

;;; graphviz-dot-mode.el --- Mode for the dot-language used by graphviz (att).

;; Copyright (C) 2002 - 2015 Pieter Pareit <[email protected]>

;; This program is free software; you can redistribute it and/or
;; modify it under the terms of the GNU General Public License as
;; published by the Free Software Foundation; either version 2 of
;; the License, or (at your option) any later version.

;; This program is distributed in the hope that it will be
;; useful, but WITHOUT ANY WARRANTY; without even the implied
;; warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
;; PURPOSE.  See the GNU General Public License for more details.
…

;; Authors: Pieter Pareit <[email protected]>
;;          Rubens Ramos <rubensr AT users.sourceforge.net>
;;          Eric Anderson http://www.ece.cmu.edu/~andersoe/
;; Maintainer: Pieter Pareit <[email protected]>
;; Homepage: http://ppareit.github.com/graphviz-dot-mode/
;; Created: 28 Oct 2002
;; Last modified: 25 May 2015
;; Version: 0.3.10
;; Keywords: mode dot dot-language dotlanguage graphviz graphs att

Introduction

This manual describes how to install and use graphviz-dot-mode, an Emacs package for working with Graphviz DOT-format files. The features of this package help you to create .dot or .gv files containing syntax compatible with the separate Graphviz package and use Graphviz to convert these files to diagrams.

Graphviz is a set of open source graph visualization tools created by AT&T Labs Research. A graph is a way of representing information as a network of connected nodes (shapes) and edges (lines). Graphviz is documented at http://graphviz.org.

The powerful text editor, Emacs, was created in 1976 by Richard Stallman. It is highly customizable and has 40 years of other extensions. GNU Emacs is documented at https://www.gnu.org/software/emacs/. XEmacs is documented at http://www.xemacs.org.

Installing

This chapter describes how to install graphviz-dot-mode.

Recommended Installation

The recommended way to install the package graphviz-dot-mode is to use package.el and M-x package-install.

To install graphviz-dot-mode, first add the MELPA Stable archive to the list of archives used by package.el (if it is not alrady there) by adding the following lines to your .emacs or other Emacs startup file. Then restart Emacs.

(require 'package)
(add-to-list 'package-archives
             '("melpa-stable" . "https://stable.melpa.org/packages/"))
             
(package-initialize)

(For more detailed and comprehensive instructions about using MELPA, please see https://melpa.org/#/getting-started.)

After restarting Emacs, type the following to install graphviz-dot-mode.

M-x package-install RET graphviz-dot-mode RET.

When installed this way using the package manager, graphviz-dot-mode will be activated automatically for file names ending in either .dot or .gv.

Installing by Hand

You can manually download and install graphviz-dot-mode, but it is best to use the recommended method above if you don’t already know how to manually install an Emacs program.

You may download graphviz-dot-mode.el from http://ppareit.github.io/graphviz-dot-mode/ and follow the instructions that you find there.

Installing this Info Manual

This section describes how to install this manual so that it may be used from within Emacs using its info reader.

1. Obtain the file containing the info-format version of this manual, graphviz-dot-mode.info.gz (See https://github.com/daniel-birket/graphviz-dot-mode.)

2. In Emacs, use C-h v Info-directory-listRET to display the contents of the Info-directory-list variable. (This may be the same as the INFOPATH enviroment variable.)

3. Copy the graphviz-dot-mode.info.gz file to one of the directories in the Info-directory-list variable.

4. Use install-info to add an entry for the new graphviz-dot-mode.info.gz file into the dir file in the info directory where you copied the file.

5. In Emacs, use C-h i d m graphviz-dot-mode RET to display this help file.

The Makefile in the texinfo subdirectory of the GitHub archive at https://github.com/daniel-birket/graphviz-dot-mode includes an option to install the info file with make install. You must first modify the variables in the top of the Makefile to use the correct directories and files for your system.

You must install GNU Texinfo v6.4 to use install-info or the Makefile.

Using graphviz-dot-mode

This chapter describes how to use graphviz-dot-mode.

Compiling & Viewing

This section describes how to use compile and view functions. See Compile & View Variables.

C-c c (compile)
This command compiles the current dot file visited by the Emacs buffer. The output file is in the same directory and has the extension determined by the variable graphviz-dot-preview-extension.

C-x ` (next-error)
This command will jump to the location in the source file of the next error from the most recent compile. Use C-c c to compile first.

C-c p (graphviz-dot-preview)
This command compiles and then (if it compiled successfully) shows the output of the current dot file visited by the Emacs buffer, provided that GNU Emacs or XEmacs is running on a graphical display capable of displaying the graphic file output by dot.

See image-file-name-extensions in GNU Emacs or image-formats-alist in XEmacs to customize the graphic files that can be displayed.

C-c v (graphviz-dot-view)
This command invokes an external viewer specified by the variable graphviz-dot-view-command. If graphviz-dot-view-edit-command is t, you will be prompted to enter a new graphviz-dot-view-command. If graphviz-dot-save-before-view is t, the buffer is saved before the external viwer command is invoked.

(See http://graphviz.org/content/resources for a list of Graphviz viewers and editors.)

Editing

This section describes how to edit with graphviz-dot-mode. See Editing Variables.

Indenting

C-M-q (graphviz-dot-indent-graph)
This command will indent the graph, diagraph, or subgraph at point and any subgraph within it.

TAB
This key will automatically indent the line. It does not perform completion.

M-j (comment-indent-newline)
See Commenting

RET (electric-graphviz-dot-terminate-line)
If the variable graphviz-dot-auto-indent-on-newline is t, RET will insert a newline and indent the next line.

{ (electric-graphviz-dot-open-brace)
If the variable graphviz-dot-auto-indent-on-braces is t, { will insert a {, newline and indent the next line.

} (electric-graphviz-dot-close-brace)
If the variable graphviz-dot-auto-indent-on-braces is t, } will insert a }, newline and indent the next line.

; (electric-graphviz-dot-semi)
If the variable graphviz-dot-auto-indent-on-semi is t, ; will insert a ;, newline and indent the next line.

Completion

M-t (graphviz-dot-complete-word)
This command will complete the attribute or value keyword at point. If more than one completion is possible, a list is displayed in the minbuffer.

See Completion Variables

Commenting

M-; (comment-dwim)
This command will perform the comment command you want (Do What I Mean). If the region is active and transient-mark-mode is on, it will comment the region, unless it only consists of comments, in which case it will un-comment the region. Else, if the current line is empty, it will insert a blank comment line, otherwise it will append a comment to the line and indent it.

Use C-u M-; to kill the comment on the current line.

C-x C-; (comment-line)
This command will comment or un-comment the current line.

M-j (comment-indent-newline)
This command will break line the at point and indent, continuing a comment if within one. This indents the body of the continued comment under the previous comment line.

C-c C-c (comment-region)
This command will comment-out the region.

You may also use M-; (comment-dwin) to comment the region if transient-mark-mode is on.

C-c C-u (graphviz-dot-uncomment-region)
This command will un-comment the region.

You may also use C-u M-; (comment-dwin) to un-comment the region if transient-mark-mode is on.

Customizing

This section describes the customizable variables of graphviz-dot-mode. You may customize variables by typing

M-x graphviz-dot-customize RET
This function invokes the Emacs customization facility to allow you to view and change the graphviz-dot-mode variables below.

Compile & View Variables

This section describes variables related to compiling and viewing. See Compiling & Viewing

graphviz-dot-dot-programgraphviz-dot-dot-program
string, default: “dot”

This variable determines the command name (and path, if necessary) used to invoke the Graphviz dot program. The C-c c (compile) function invokes this command.

graphviz-dot-preview-extensiongraphviz-dot-preview-extension
string, default “png”

This variable determines the file extension used for the C-c c (compile) and C-c p (graphviz-dot-preview) functions. The format for the compile command is

dot -T<extension> <filename>.dot > <filename>.<extension>

graphviz-dot-save-before-viewgraphviz-dot-save-before-view
boolean, default t

This variable controls whether the buffer will be saved to the visited file before the C-c v (graphviz-dot-view) function invokes the external dot-file viewer command. Set this boolean variable to t (true) or nil (false).

graphviz-dot-view-commandgraphviz-dot-view-command
string, default: “doted %s”

This variable determines the command name (and path, if necessary) used to invoke an external dot-file viewer program. The C-c v (graphviz-dot-view) function invokes this command. The name of the file visited by the buffer will be substituted for %s in this string.

(See http://graphviz.org/content/resources for a list of Graphviz viewers and editors.)

graphviz-dot-view-edit-commandgraphviz-dot-view-edit-command
boolean, default: nil

This variable controls whether you will be prompted for the external dot-file viewer command name when you use C-c v graphviz-dot-view. Set this to t (true) to be prompted to edit the viewer command variable graphviz-dot-view-command every time you use C-c v or nil to avoid the prompt.

Editing Variables

This section describes variables related to editing. See Editing

Indenting Variables

This subsection describes variables related to indenting.

graphviz-dot-auto-indent-on-bracesgraphviz-dot-auto-indent-on-braces
{ } boolean, default nil

This variable controls whether the functions electric-graphviz-dot-open-brace and electric-graphviz-dot-close-brace are called when { and } are typed. Set this boolean variable to t (true) or nil (false).

graphviz-dot-auto-indent-on-newlinegraphviz-dot-auto-indent-on-newline
boolean, default t

This variable controls whether the function electric-graphviz-dot-terminate-line is called when a line is terminated with a newline. Set this boolean variable to t (true) or nil (false).

graphviz-dot-auto-indent-on-semigraphviz-dot-auto-indent-on-semi
boolean, default t

This variable controls whether the function electric-graphviz-dot-semi is called when a semicolon ; is typed. Set this boolean variable to t (true) or nil (false).

graphviz-dot-indent-widthgraphviz-dot-indent-width
integer, default: default-tab-width

This variable determines the indentation used in graphviz-dot-mode buffers.

Completion Variables

This subsection describes variables related to completion.

graphviz-dot-delete-completionsgraphviz-dot-delete-completions
boolean, default: nil

This variable controls whether the completion buffer is automatically deleted when a key is pressed. Set this boolean variable to t (true) or nil (false).

graphviz-dot-toggle-completionsgraphviz-dot-toggle-completions
boolean, default: nil

This variable controls whether repeated use of M-t graphviz-dot-complete-word will toggle the display of possible completions in the minibuffer. If this variable is set to nil, when there are more than one possible completions, a buffer will display all completions. Set this boolean variable to t (true) or nil (false).

Keyword Variables

This section describes the variables containing DOT-language keywords, which may change if Graphviz is updated. You may update these variables after new releases of Graphvizfrom http://www.graphviz.org/doc/schema/attributes.xml .

graphviz-dot-attr-keywordsgraphviz-dot-attr-keywords
list of strings, default: (“graph” “digraph” … )

This variable holds a list of keywords for attribute names in a graph. This is used by the M-t auto completion function. The actual completion tables are built when the mode is loaded, so changes to this variable are not immediately visible.

graphviz-dot-value-keywordsgraphviz-dot-value-keywords
list of strings, default: (“true” “false” … )

This variable holds a list of keywords for attribute values in a graph. This is used by the M-t auto completion function. The actual completion tables are built when the mode is loaded, so changes to this variable are not immediately visible.

Mode Hook

graphviz-dot-mode-hookgraphviz-dot-mode-hook
list of functions, default: nil

This variable determins which functions are called when graphviz-dot-mode starts. To use it, add a line like below to your .emacs or other startup file.

(add-hook 'graphviz-dot-mode-hook 'my-hook)

Credits

graphviz-dot-mode was written by:

• Pieter Pareit [email protected]

• Rubens Ramos [email protected]

• Eric Anderson http://www.ece.cmu.edu/~andersoe/

Other contributors are noted in the version history in the graphviz-dot-mode.el file and the commit history on GitHub.

The source code is maintained on GitHub at https://github.com/ppareit/graphviz-dot-mode by Pieter Pareit ([email protected]). Please email software comments, suggestions and corrections there.

This manual is maintained on GitHub at https://github.com/daniel-birket/graphviz-dot-mode by Daniel Birket ([email protected]). Please submit document errata to the issue tracker there.

GNU General Public License 2.0

Version 2, June 1991 Copyright © 1989, 1991 Free Software Foundation, Inc. 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA

Everyone is permitted to copy and distribute verbatim copies
of this license document, but changing it is not allowed.

Preamble

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TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION

1. This License applies to any program or other work which contains a notice placed by the copyright holder saying it may be distributed under the terms of this General Public License. The “Program”, below, refers to any such program or work, and a “work based on the Program” means either the Program or any derivative work under copyright law: that is to say, a work containing the Program or a portion of it, either verbatim or with modifications and/or translated into another language. (Hereinafter, translation is included without limitation in the term “modification”.) Each licensee is addressed as “you”.

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Appendix: How to Apply These Terms to Your New Programs

If you develop a new program, and you want it to be of the greatest possible use to the public, the best way to achieve this is to make it free software which everyone can redistribute and change under these terms.

To do so, attach the following notices to the program. It is safest to attach them to the start of each source file to most effectively convey the exclusion of warranty; and each file should have at least the “copyright” line and a pointer to where the full notice is found.

one line to give the program's name and a brief idea of what it does.
Copyright (C) yyyy  name of author

This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.

Also add information on how to contact you by electronic and paper mail.

If the program is interactive, make it output a short notice like this when it starts in an interactive mode:

Gnomovision version 69, Copyright (C) year name of author
Gnomovision comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
This is free software, and you are welcome to redistribute it
under certain conditions; type `show c' for details.

The hypothetical commands ‘show w’ and ‘show c’ should show the appropriate parts of the General Public License. Of course, the commands you use may be called something other than ‘show w’ and ‘show c’; they could even be mouse-clicks or menu items—whatever suits your program.

You should also get your employer (if you work as a programmer) or your school, if any, to sign a “copyright disclaimer” for the program, if necessary. Here is a sample; alter the names:

Yoyodyne, Inc., hereby disclaims all copyright interest in the program
`Gnomovision' (which makes passes at compilers) written by James Hacker.

signature of Ty Coon, 1 April 1989
Ty Coon, President of Vice

This General Public License does not permit incorporating your program into proprietary programs. If your program is a subroutine library, you may consider it more useful to permit linking proprietary applications with the library. If this is what you want to do, use the GNU Lesser General Public License instead of this License.

GNU Free Documentation License

Version 1.3, 3 November 2008 Copyright © 2000, 2001, 2002, 2007, 2008 Free Software Foundation, Inc. http://fsf.org/

Everyone is permitted to copy and distribute verbatim copies
of this license document, but changing it is not allowed.

1. PREAMBLE

   The purpose of this License is to make a manual, textbook, or other functional and useful document free in the sense of freedom: to assure everyone the effective freedom to copy and redistribute it, with or without modifying it, either commercially or noncommercially. Secondarily, this License preserves for the author and publisher a way to get credit for their work, while not being considered responsible for modifications made by others.

   This License is a kind of “copyleft”, which means that derivative works of the document must themselves be free in the same sense. It complements the GNU General Public License, which is a copyleft license designed for free software.

   We have designed this License in order to use it for manuals for free software, because free software needs free documentation: a free program should come with manuals providing the same freedoms that the software does. But this License is not limited to software manuals; it can be used for any textual work, regardless of subject matter or whether it is published as a printed book. We recommend this License principally for works whose purpose is instruction or reference.

2. APPLICABILITY AND DEFINITIONS

   This License applies to any manual or other work, in any medium, that contains a notice placed by the copyright holder saying it can be distributed under the terms of this License. Such a notice grants a world-wide, royalty-free license, unlimited in duration, to use that work under the conditions stated herein. The “Document”, below, refers to any such manual or work. Any member of the public is a licensee, and is addressed as “you”. You accept the license if you copy, modify or distribute the work in a way requiring permission under copyright law.

   A “Modified Version” of the Document means any work containing the Document or a portion of it, either copied verbatim, or with modifications and/or translated into another language.

   A “Secondary Section” is a named appendix or a front-matter section of the Document that deals exclusively with the relationship of the publishers or authors of the Document to the Document’s overall subject (or to related matters) and contains nothing that could fall directly within that overall subject. (Thus, if the Document is in part a textbook of mathematics, a Secondary Section may not explain any mathematics.) The relationship could be a matter of historical connection with the subject or with related matters, or of legal, commercial, philosophical, ethical or political position regarding them.

   The “Invariant Sections” are certain Secondary Sections whose titles are designated, as being those of Invariant Sections, in the notice that says that the Document is released under this License. If a section does not fit the above definition of Secondary then it is not allowed to be designated as Invariant. The Document may contain zero Invariant Sections. If the Document does not identify any Invariant Sections then there are none.

   The “Cover Texts” are certain short passages of text that are listed, as Front-Cover Texts or Back-Cover Texts, in the notice that says that the Document is released under this License. A Front-Cover Text may be at most 5 words, and a Back-Cover Text may be at most 25 words.

   A “Transparent” copy of the Document means a machine-readable copy, represented in a format whose specification is available to the general public, that is suitable for revising the document straightforwardly with generic text editors or (for images composed of pixels) generic paint programs or (for drawings) some widely available drawing editor, and that is suitable for input to text formatters or for automatic translation to a variety of formats suitable for input to text formatters. A copy made in an otherwise Transparent file format whose markup, or absence of markup, has been arranged to thwart or discourage subsequent modification by readers is not Transparent. An image format is not Transparent if used for any substantial amount of text. A copy that is not “Transparent” is called “Opaque”.

   Examples of suitable formats for Transparent copies include plain ASCII without markup, Texinfo input format, LaTEX input format, SGML or XML using a publicly available DTD, and standard-conforming simple HTML, PostScript or PDF designed for human modification. Examples of transparent image formats include PNG, XCF and JPG. Opaque formats include proprietary formats that can be read and edited only by proprietary word processors, SGML or XML for which the DTD and/or processing tools are not generally available, and the machine-generated HTML, PostScript or PDF produced by some word processors for output purposes only.

   The “Title Page” means, for a printed book, the title page itself, plus such following pages as are needed to hold, legibly, the material this License requires to appear in the title page. For works in formats which do not have any title page as such, “Title Page” means the text near the most prominent appearance of the work’s title, preceding the beginning of the body of the text.

   The “publisher” means any person or entity that distributes copies of the Document to the public.

   A section “Entitled XYZ” means a named subunit of the Document whose title either is precisely XYZ or contains XYZ in parentheses following text that translates XYZ in another language. (Here XYZ stands for a specific section name mentioned below, such as “Acknowledgements”, “Dedications”, “Endorsements”, or “History”.) To “Preserve the Title” of such a section when you modify the Document means that it remains a section “Entitled XYZ” according to this definition.

   The Document may include Warranty Disclaimers next to the notice which states that this License applies to the Document. These Warranty Disclaimers are considered to be included by reference in this License, but only as regards disclaiming warranties: any other implication that these Warranty Disclaimers may have is void and has no effect on the meaning of this License.

3. VERBATIM COPYING

   You may copy and distribute the Document in any medium, either commercially or noncommercially, provided that this License, the copyright notices, and the license notice saying this License applies to the Document are reproduced in all copies, and that you add no other conditions whatsoever to those of this License. You may not use technical measures to obstruct or control the reading or further copying of the copies you make or distribute. However, you may accept compensation in exchange for copies. If you distribute a large enough number of copies you must also follow the conditions in section 3.

   You may also lend copies, under the same conditions stated above, and you may publicly display copies.

4. COPYING IN QUANTITY

   If you publish printed copies (or copies in media that commonly have printed covers) of the Document, numbering more than 100, and the Document’s license notice requires Cover Texts, you must enclose the copies in covers that carry, clearly and legibly, all these Cover Texts: Front-Cover Texts on the front cover, and Back-Cover Texts on the back cover. Both covers must also clearly and legibly identify you as the publisher of these copies. The front cover must present the full title with all words of the title equally prominent and visible. You may add other material on the covers in addition. Copying with changes limited to the covers, as long as they preserve the title of the Document and satisfy these conditions, can be treated as verbatim copying in other respects.

   If the required texts for either cover are too voluminous to fit legibly, you should put the first ones listed (as many as fit reasonably) on the actual cover, and continue the rest onto adjacent pages.

   If you publish or distribute Opaque copies of the Document numbering more than 100, you must either include a machine-readable Transparent copy along with each Opaque copy, or state in or with each Opaque copy a computer-network location from which the general network-using public has access to download using public-standard network protocols a complete Transparent copy of the Document, free of added material. If you use the latter option, you must take reasonably prudent steps, when you begin distribution of Opaque copies in quantity, to ensure that this Transparent copy will remain thus accessible at the stated location until at least one year after the last time you distribute an Opaque copy (directly or through your agents or retailers) of that edition to the public.

   It is requested, but not required, that you contact the authors of the Document well before redistributing any large number of copies, to give them a chance to provide you with an updated version of the Document.

5. MODIFICATIONS

   You may copy and distribute a Modified Version of the Document under the conditions of sections 2 and 3 above, provided that you release the Modified Version under precisely this License, with the Modified Version filling the role of the Document, thus licensing distribution and modification of the Modified Version to whoever possesses a copy of it. In addition, you must do these things in the Modified Version:

   1. Use in the Title Page (and on the covers, if any) a title distinct from that of the Document, and from those of previous versions (which should, if there were any, be listed in the History section of the Document). You may use the same title as a previous version if the original publisher of that version gives permission.

   2. List on the Title Page, as authors, one or more persons or entities responsible for authorship of the modifications in the Modified Version, together with at least five of the principal authors of the Document (all of its principal authors, if it has fewer than five), unless they release you from this requirement.

   3. State on the Title page the name of the publisher of the Modified Version, as the publisher.

   4. Preserve all the copyright notices of the Document.

   5. Add an appropriate copyright notice for your modifications adjacent to the other copyright notices.

   6. Include, immediately after the copyright notices, a license notice giving the public permission to use the Modified Version under the terms of this License, in the form shown in the Addendum below.

   7. Preserve in that license notice the full lists of Invariant Sections and required Cover Texts given in the Document’s license notice.

   8. Include an unaltered copy of this License.

   9. Preserve the section Entitled “History”, Preserve its Title, and add to it an item stating at least the title, year, new authors, and publisher of the Modified Version as given on the Title Page. If there is no section Entitled “History” in the Document, create one stating the title, year, authors, and publisher of the Document as given on its Title Page, then add an item describing the Modified Version as stated in the previous sentence.

   10. Preserve the network location, if any, given in the Document for public access to a Transparent copy of the Document, and likewise the network locations given in the Document for previous versions it was based on. These may be placed in the “History” section. You may omit a network location for a work that was published at least four years before the Document itself, or if the original publisher of the version it refers to gives permission.

   11. For any section Entitled “Acknowledgements” or “Dedications”, Preserve the Title of the section, and preserve in the section all the substance and tone of each of the contributor acknowledgements and/or dedications given therein.

   12. Preserve all the Invariant Sections of the Document, unaltered in their text and in their titles. Section numbers or the equivalent are not considered part of the section titles.

   13. Delete any section Entitled “Endorsements”. Such a section may not be included in the Modified Version.

   14. Do not retitle any existing section to be Entitled “Endorsements” or to conflict in title with any Invariant Section.

   15. Preserve any Warranty Disclaimers.

   If the Modified Version includes new front-matter sections or appendices that qualify as Secondary Sections and contain no material copied from the Document, you may at your option designate some or all of these sections as invariant. To do this, add their titles to the list of Invariant Sections in the Modified Version’s license notice. These titles must be distinct from any other section titles.

   You may add a section Entitled “Endorsements”, provided it contains nothing but endorsements of your Modified Version by various parties—for example, statements of peer review or that the text has been approved by an organization as the authoritative definition of a standard.

   You may add a passage of up to five words as a Front-Cover Text, and a passage of up to 25 words as a Back-Cover Text, to the end of the list of Cover Texts in the Modified Version. Only one passage of Front-Cover Text and one of Back-Cover Text may be added by (or through arrangements made by) any one entity. If the Document already includes a cover text for the same cover, previously added by you or by arrangement made by the same entity you are acting on behalf of, you may not add another; but you may replace the old one, on explicit permission from the previous publisher that added the old one.

   The author(s) and publisher(s) of the Document do not by this License give permission to use their names for publicity for or to assert or imply endorsement of any Modified Version.

6. COMBINING DOCUMENTS

   You may combine the Document with other documents released under this License, under the terms defined in section 4 above for modified versions, provided that you include in the combination all of the Invariant Sections of all of the original documents, unmodified, and list them all as Invariant Sections of your combined work in its license notice, and that you preserve all their Warranty Disclaimers.

   The combined work need only contain one copy of this License, and multiple identical Invariant Sections may be replaced with a single copy. If there are multiple Invariant Sections with the same name but different contents, make the title of each such section unique by adding at the end of it, in parentheses, the name of the original author or publisher of that section if known, or else a unique number. Make the same adjustment to the section titles in the list of Invariant Sections in the license notice of the combined work.

   In the combination, you must combine any sections Entitled “History” in the various original documents, forming one section Entitled “History”; likewise combine any sections Entitled “Acknowledgements”, and any sections Entitled “Dedications”. You must delete all sections Entitled “Endorsements.”

7. COLLECTIONS OF DOCUMENTS

   You may make a collection consisting of the Document and other documents released under this License, and replace the individual copies of this License in the various documents with a single copy that is included in the collection, provided that you follow the rules of this License for verbatim copying of each of the documents in all other respects.

   You may extract a single document from such a collection, and distribute it individually under this License, provided you insert a copy of this License into the extracted document, and follow this License in all other respects regarding verbatim copying of that document.

8. AGGREGATION WITH INDEPENDENT WORKS

   A compilation of the Document or its derivatives with other separate and independent documents or works, in or on a volume of a storage or distribution medium, is called an “aggregate” if the copyright resulting from the compilation is not used to limit the legal rights of the compilation’s users beyond what the individual works permit. When the Document is included in an aggregate, this License does not apply to the other works in the aggregate which are not themselves derivative works of the Document.

   If the Cover Text requirement of section 3 is applicable to these copies of the Document, then if the Document is less than one half of the entire aggregate, the Document’s Cover Texts may be placed on covers that bracket the Document within the aggregate, or the electronic equivalent of covers if the Document is in electronic form. Otherwise they must appear on printed covers that bracket the whole aggregate.

9. TRANSLATION

   Translation is considered a kind of modification, so you may distribute translations of the Document under the terms of section 4. Replacing Invariant Sections with translations requires special permission from their copyright holders, but you may include translations of some or all Invariant Sections in addition to the original versions of these Invariant Sections. You may include a translation of this License, and all the license notices in the Document, and any Warranty Disclaimers, provided that you also include the original English version of this License and the original versions of those notices and disclaimers. In case of a disagreement between the translation and the original version of this License or a notice or disclaimer, the original version will prevail.

   If a section in the Document is Entitled “Acknowledgements”, “Dedications”, or “History”, the requirement (section 4) to Preserve its Title (section 1) will typically require changing the actual title.

10. TERMINATION

    You may not copy, modify, sublicense, or distribute the Document except as expressly provided under this License. Any attempt otherwise to copy, modify, sublicense, or distribute it is void, and will automatically terminate your rights under this License.

    However, if you cease all violation of this License, then your license from a particular copyright holder is reinstated (a) provisionally, unless and until the copyright holder explicitly and finally terminates your license, and (b) permanently, if the copyright holder fails to notify you of the violation by some reasonable means prior to 60 days after the cessation.

    Moreover, your license from a particular copyright holder is reinstated permanently if the copyright holder notifies you of the violation by some reasonable means, this is the first time you have received notice of violation of this License (for any work) from that copyright holder, and you cure the violation prior to 30 days after your receipt of the notice.

    Termination of your rights under this section does not terminate the licenses of parties who have received copies or rights from you under this License. If your rights have been terminated and not permanently reinstated, receipt of a copy of some or all of the same material does not give you any rights to use it.

11. FUTURE REVISIONS OF THIS LICENSE

    The Free Software Foundation may publish new, revised versions of the GNU Free Documentation License from time to time. Such new versions will be similar in spirit to the present version, but may differ in detail to address new problems or concerns. See http://www.gnu.org/copyleft/.

    Each version of the License is given a distinguishing version number. If the Document specifies that a particular numbered version of this License “or any later version” applies to it, you have the option of following the terms and conditions either of that specified version or of any later version that has been published (not as a draft) by the Free Software Foundation. If the Document does not specify a version number of this License, you may choose any version ever published (not as a draft) by the Free Software Foundation. If the Document specifies that a proxy can decide which future versions of this License can be used, that proxy’s public statement of acceptance of a version permanently authorizes you to choose that version for the Document.

12. RELICENSING

    “Massive Multiauthor Collaboration Site” (or “MMC Site”) means any World Wide Web server that publishes copyrightable works and also provides prominent facilities for anybody to edit those works. A public wiki that anybody can edit is an example of such a server. A “Massive Multiauthor Collaboration” (or “MMC”) contained in the site means any set of copyrightable works thus published on the MMC site.

    “CC-BY-SA” means the Creative Commons Attribution-Share Alike 3.0 license published by Creative Commons Corporation, a not-for-profit corporation with a principal place of business in San Francisco, California, as well as future copyleft versions of that license published by that same organization.

    “Incorporate” means to publish or republish a Document, in whole or in part, as part of another Document.

    An MMC is “eligible for relicensing” if it is licensed under this License, and if all works that were first published under this License somewhere other than this MMC, and subsequently incorporated in whole or in part into the MMC, (1) had no cover texts or invariant sections, and (2) were thus incorporated prior to November 1, 2008.

    The operator of an MMC Site may republish an MMC contained in the site under CC-BY-SA on the same site at any time before August 1, 2009, provided the MMC is eligible for relicensing.

ADDENDUM: How to use this License for your documents

To use this License in a document you have written, include a copy of the License in the document and put the following copyright and license notices just after the title page:

  Copyright (C)  year  your name.
  Permission is granted to copy, distribute and/or modify this document
  under the terms of the GNU Free Documentation License, Version 1.3
  or any later version published by the Free Software Foundation;
  with no Invariant Sections, no Front-Cover Texts, and no Back-Cover
  Texts.  A copy of the license is included in the section entitled ``GNU
  Free Documentation License''.

If you have Invariant Sections, Front-Cover Texts and Back-Cover Texts, replace the “with…Texts.” line with this:

    with the Invariant Sections being list their titles, with
    the Front-Cover Texts being list, and with the Back-Cover Texts
    being list.

If you have Invariant Sections without Cover Texts, or some other combination of the three, merge those two alternatives to suit the situation.

If your document contains nontrivial examples of program code, we recommend releasing these examples in parallel under your choice of free software license, such as the GNU General Public License, to permit their use in free software.

Functions & Variables

Keys and Concepts