.. This is part of the Zrythm Manual.
   Copyright (C) 2019 Alexandros Theodotou <alex at zrythm dot org>
   See the file index.rst for copying conditions.

GNU Free Documentation License
==============================

Version 1.3, 3 November 2008

Copyright (C) 2000, 2001, 2002, 2007, 2008 Free Software Foundation,
Inc. \ https://fsf.org/

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 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.

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
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to any such manual or work. Any member of the public is a licensee, and
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A “Modified Version” of the Document means any work containing the
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A “Secondary Section” is a named appendix or a front-matter section of
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The “Invariant Sections” are certain Secondary Sections whose titles are
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The “Cover Texts” are certain short passages of text that are listed, as
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The “publisher” means any person or entity that distributes copies of
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section “Entitled XYZ” according to this definition.

The Document may include Warranty Disclaimers next to the notice which
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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.

2. 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
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compensation in exchange for copies. If you distribute a large enough
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You may also lend copies, under the same conditions stated above, and
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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 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
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until at least one year after the last time you distribute an Opaque
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It is requested, but not required, that you contact the authors of the
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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 previous 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 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.
-  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 “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.
-  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 section 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 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.

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 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”.

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 document, 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 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.

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 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.

9. 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
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unless and until the copyright holder explicitly and finally terminates
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Moreover, your license from a particular copyright holder is reinstated
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of violation of this License (for any work) from that copyright holder,
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notice.

Termination of your rights under this section does not terminate the
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reinstated, receipt of a copy of some or all of the same material does
not give you any rights to use it.

10. 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 https://www.gnu.org/licenses/.

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
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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.

11. 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
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“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.
