GFDL(7) - man - phpMan

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GFDL(7) GNU GFDL(7)

NAME
gfdl - GNU Free Documentation License

DESCRIPTION
GNU Free Documentation License

Version 1.2, November 2002

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

0. 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 noncommer‐
cially. 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 Li‐
cense, 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.

1. 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 Li‐
cense. 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 re‐
quiring permission under copyright law.

A ``Modified Version'' of the Document means any work containing the Document or a por‐
tion 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 re‐
vising 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 vari‐
ety of formats suitable for input to text formatters. A copy made in an otherwise Trans‐
parent 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 ``Transpar‐
ent'' is called ``Opaque''.

Examples of suitable formats for Transparent copies include plain ASCII without markup,
Texinfo input format, LaTeX input format, @acronym{SGML} or @acronym{XML} using a pub‐
licly available @acronym{DTD}, and standard-conforming simple @acronym{HTML}, PostScript
or @acronym{PDF} designed for human modification. Examples of transparent image formats
include @acronym{PNG}, @acronym{XCF} and @acronym{JPG}. Opaque formats include propri‐
etary formats that can be read and edited only by proprietary word processors, @acro‐
nym{SGML} or @acronym{XML} for which the @acronym{DTD} and/or processing tools are not
generally available, and the machine-generated @acronym{HTML}, PostScript or @acro‐
nym{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 an‐
other 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 sec‐
tion ``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 in‐
cluded 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.

2. VERBATIM COPYING

You may copy and distribute the Document in any medium, either commercially or noncommer‐
cially, 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 distrib‐
ute. 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.

3. 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 net‐
work-using public has access to download using public-standard network protocols a com‐
plete 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 be‐
fore redistributing any large number of copies, to give them a chance to provide you with
an updated version of the Document.

4. 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:

A. 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 pre‐
vious version if the original publisher of that version gives permission.

B. 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.

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

D. Preserve all the copyright notices of the Document.

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

F. 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.

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

H. Include an unaltered copy of this License.

I. 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 Docu‐
ment, 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.

J. 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 ``His‐
tory'' 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 ver‐
sion it refers to gives permission.

K. 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.

L. 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 sec‐
tion titles.

M. Delete any section Entitled ``Endorsements''. Such a section may not be included in
the Modified Version.

N. Do not retitle any existing section to be Entitled ``Endorsements'' or to conflict in
title with any Invariant Section.

O. 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 op‐
tion 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 en‐
dorsements 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 defini‐
tion 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 Ver‐
sion. 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 Ver‐
sion.

5. 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 In‐
variant 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 com‐
bined work.

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

6. 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 docu‐
ment, and follow this License in all other respects regarding verbatim copying of that
document.

7. AGGREGATION WITH INDEPENDENT WORKS

A compilation of the Document or its derivatives with other separate and independent doc‐
uments 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 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.

8. 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 transla‐
tions 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 li‐
cense notices in the Document, and any Warrany Disclaimers, provided that you also in‐
clude the original English version of this License and the original versions of those no‐
tices and disclaimers. In case of a disagreement between the translation and the origi‐
nal 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 ``His‐
tory'', the requirement (section 4) to Preserve its Title (section 1) will typically re‐
quire changing the actual title.

9. TERMINATION

You may not copy, modify, sublicense, or distribute the Document except as expressly pro‐
vided for under this License. Any other attempt to copy, modify, sublicense or distrib‐
ute the Document is void, and will automatically terminate your rights under this Li‐
cense. 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 compli‐
ance.

10. FUTURE REVISIONS OF THIS LICENSE

The Free Software Foundation may publish new, revised versions of the GNU Free Documenta‐
tion 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'' ap‐
plies 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 Li‐
cense, you may choose any version ever published (not as a draft) by the Free Software
Foundation.

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 doc‐
ument 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 Pub‐
lic License, to permit their use in free software.