GNU Free Documentation License
Version 1.2, November 2002
Copyright © 2000, 2001, 2002 Free Software Foundation,
Inc. 675 Mass Ave, Cambridge, MA 02139, USA
Everyone is permitted to copy and distribute verbatim copies
of this license document, but changing it is not allowed.
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 , 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.
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.
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.
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 .
You may also lend copies, under the same conditions
stated above, and you may publicly display copies.
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.
Modifications
You may copy and distribute a Modified Version of the
Document under the conditions of sections and 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:
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.
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.
State on the Title page the name of the
publisher of the Modified Version, as the
publisher.
Preserve all the copyright notices of the
Document.
Add an appropriate copyright notice for your
modifications adjacent to the other copyright
notices.
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.
Preserve in that license notice the full lists
of Invariant Sections and required Cover Texts given
in the Document's license notice.
Include an unaltered copy of this License.
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.
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.
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.
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.
Delete any section Entitled
Endorsements
. Such a section may not
be included in the Modified Version.
Do not retitle any existing section to be
Entitled Endorsements
or to conflict in
title with any Invariant Section.
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.
Combining documents
You may combine the Document with other documents
released under this License, under the terms defined in
section 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
.
Collection 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.
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 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.
Translations
Translation is considered a kind of modification, so you
may distribute translations of the Document under the terms of
section . 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 ) to Preserve its Title
(section ) will
typically require changing the actual title.
Termination
You may not copy, modify, sublicense, or distribute the
Document except as expressly provided for under this License.
Any other attempt to copy, modify, sublicense or distribute
the Document is void, and will automatically terminate your
rights under this License. However, parties who have received
copies, or rights, from you under this License will not have
their licenses terminated so long as such parties remain in
full compliance.
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 .
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.
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 1.2 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.