1 # The GNU Free Documentation License.
3 Version 1.3, 3 November 2008
6 # This file is intended to be included within another document.
9 Copyright \copy{} 2000, 2001, 2002, 2007, 2008 Free Software Foundation, Inc.
12 Everyone is permitted to copy and distribute verbatim copies
13 of this license document, but changing it is not allowed.
18 The purpose of this License is to make a manual, textbook, or other
19 functional and useful document @@texinfo:@dfn{@@free@@texinfo:}@@
20 in the sense of freedom: to assure everyone the effective freedom
21 to copy and redistribute it, with or without modifying it, either
22 commercially or noncommercially. Secondarily, this License
23 preserves for the author and publisher a way to get credit for
24 their work, while not being considered responsible for
25 modifications made by others.
27 This License is a kind of "copyleft", which means that derivative
28 works of the document must themselves be free in the same sense.
29 It complements the GNU General Public License, which is a copyleft
30 license designed for free software.
32 We have designed this License in order to use it for manuals for
33 free software, because free software needs free documentation:
34 a free program should come with manuals providing the same freedoms
35 that the software does. But this License is not limited to
36 software manuals; it can be used for any textual work, regardless
37 of subject matter or whether it is published as a printed book. We
38 recommend this License principally for works whose purpose is
39 instruction or reference.
41 1. APPLICABILITY AND DEFINITIONS
43 This License applies to any manual or other work, in any medium,
44 that contains a notice placed by the copyright holder saying it can
45 be distributed under the terms of this License. Such a notice
46 grants a world-wide, royalty-free license, unlimited in duration,
47 to use that work under the conditions stated herein. The
48 "Document", below, refers to any such manual or work. Any member
49 of the public is a licensee, and is addressed as "you". You accept
50 the license if you copy, modify or distribute the work in a way
51 requiring permission under copyright law.
53 A "Modified Version" of the Document means any work containing the
54 Document or a portion of it, either copied verbatim, or with
55 modifications and/or translated into another language.
57 A "Secondary Section" is a named appendix or a front-matter section
58 of the Document that deals exclusively with the relationship of the
59 publishers or authors of the Document to the Document's overall
60 subject (or to related matters) and contains nothing that could
61 fall directly within that overall subject. (Thus, if the Document
62 is in part a textbook of mathematics, a Secondary Section may not
63 explain any mathematics.) The relationship could be a matter of
64 historical connection with the subject or with related matters, or
65 of legal, commercial, philosophical, ethical or political position
68 The "Invariant Sections" are certain Secondary Sections whose
69 titles are designated, as being those of Invariant Sections, in the
70 notice that says that the Document is released under this License.
71 If a section does not fit the above definition of Secondary then it
72 is not allowed to be designated as Invariant. The Document may
73 contain zero Invariant Sections. If the Document does not identify
74 any Invariant Sections then there are none.
76 The "Cover Texts" are certain short passages of text that are
77 listed, as Front-Cover Texts or Back-Cover Texts, in the notice
78 that says that the Document is released under this License.
79 A Front-Cover Text may be at most 5 words, and a Back-Cover Text
80 may be at most 25 words.
82 A "Transparent" copy of the Document means a machine-readable copy,
83 represented in a format whose specification is available to the
84 general public, that is suitable for revising the document
85 straightforwardly with generic text editors or (for images composed
86 of pixels) generic paint programs or (for drawings) some widely
87 available drawing editor, and that is suitable for input to text
88 formatters or for automatic translation to a variety of formats
89 suitable for input to text formatters. A copy made in an otherwise
90 Transparent file format whose markup, or absence of markup, has
91 been arranged to thwart or discourage subsequent modification by
92 readers is not Transparent. An image format is not Transparent if
93 used for any substantial amount of text. A copy that is not
94 "Transparent" is called "Opaque".
96 Examples of suitable formats for Transparent copies include plain
97 ASCII without markup, Texinfo input format, LaTeX input format,
98 SGML or XML using a publicly available DTD, and standard-conforming
99 simple HTML, PostScript or PDF designed for human modification.
100 Examples of transparent image formats include PNG, XCF and JPG.
101 Opaque formats include proprietary formats that can be read and
102 edited only by proprietary word processors, SGML or XML for which
103 the DTD and/or processing tools are not generally available, and
104 the machine-generated HTML, PostScript or PDF produced by some word
105 processors for output purposes only.
107 The "Title Page" means, for a printed book, the title page itself,
108 plus such following pages as are needed to hold, legibly, the
109 material this License requires to appear in the title page. For
110 works in formats which do not have any title page as such, "Title
111 Page" means the text near the most prominent appearance of the
112 work's title, preceding the beginning of the body of the text.
114 The "publisher" means any person or entity that distributes copies
115 of the Document to the public.
117 A section "Entitled XYZ" means a named subunit of the Document
118 whose title either is precisely XYZ or contains XYZ in parentheses
119 following text that translates XYZ in another language. (Here XYZ
120 stands for a specific section name mentioned below, such as
121 "Acknowledgements", "Dedications", "Endorsements", or "History".)
122 To "Preserve the Title" of such a section when you modify the
123 Document means that it remains a section "Entitled XYZ" according
126 The Document may include Warranty Disclaimers next to the notice
127 which states that this License applies to the Document. These
128 Warranty Disclaimers are considered to be included by reference in
129 this License, but only as regards disclaiming warranties: any other
130 implication that these Warranty Disclaimers may have is void and
131 has no effect on the meaning of this License.
135 You may copy and distribute the Document in any medium, either
136 commercially or noncommercially, provided that this License, the
137 copyright notices, and the license notice saying this License
138 applies to the Document are reproduced in all copies, and that you
139 add no other conditions whatsoever to those of this License. You
140 may not use technical measures to obstruct or control the reading
141 or further copying of the copies you make or distribute. However,
142 you may accept compensation in exchange for copies. If you
143 distribute a large enough number of copies you must also follow the
144 conditions in section 3.
146 You may also lend copies, under the same conditions stated above,
147 and you may publicly display copies.
149 3. COPYING IN QUANTITY
151 If you publish printed copies (or copies in media that commonly
152 have printed covers) of the Document, numbering more than 100, and
153 the Document's license notice requires Cover Texts, you must
154 enclose the copies in covers that carry, clearly and legibly, all
155 these Cover Texts: Front-Cover Texts on the front cover, and
156 Back-Cover Texts on the back cover. Both covers must also clearly
157 and legibly identify you as the publisher of these copies. The
158 front cover must present the full title with all words of the title
159 equally prominent and visible. You may add other material on the
160 covers in addition. Copying with changes limited to the covers, as
161 long as they preserve the title of the Document and satisfy these
162 conditions, can be treated as verbatim copying in other respects.
164 If the required texts for either cover are too voluminous to fit
165 legibly, you should put the first ones listed (as many as fit
166 reasonably) on the actual cover, and continue the rest onto
169 If you publish or distribute Opaque copies of the Document
170 numbering more than 100, you must either include a machine-readable
171 Transparent copy along with each Opaque copy, or state in or with
172 each Opaque copy a computer-network location from which the general
173 network-using public has access to download using public-standard
174 network protocols a complete Transparent copy of the Document, free
175 of added material. If you use the latter option, you must take
176 reasonably prudent steps, when you begin distribution of Opaque
177 copies in quantity, to ensure that this Transparent copy will
178 remain thus accessible at the stated location until at least one
179 year after the last time you distribute an Opaque copy (directly or
180 through your agents or retailers) of that edition to the public.
182 It is requested, but not required, that you contact the authors of
183 the Document well before redistributing any large number of copies,
184 to give them a chance to provide you with an updated version of the
189 You may copy and distribute a Modified Version of the Document
190 under the conditions of sections 2 and 3 above, provided that you
191 release the Modified Version under precisely this License, with the
192 Modified Version filling the role of the Document, thus licensing
193 distribution and modification of the Modified Version to whoever
194 possesses a copy of it. In addition, you must do these things in
195 the Modified Version:
197 #+attr_texinfo: :enum A
198 1. Use in the Title Page (and on the covers, if any) a title
199 distinct from that of the Document, and from those of previous
200 versions (which should, if there were any, be listed in the
201 History section of the Document). You may use the same title as
202 a previous version if the original publisher of that version
205 2. List on the Title Page, as authors, one or more persons or
206 entities responsible for authorship of the modifications in the
207 Modified Version, together with at least five of the principal
208 authors of the Document (all of its principal authors, if it has
209 fewer than five), unless they release you from this requirement.
211 3. State on the Title page the name of the publisher of the
212 Modified Version, as the publisher.
214 4. Preserve all the copyright notices of the Document.
216 5. Add an appropriate copyright notice for your modifications
217 adjacent to the other copyright notices.
219 6. Include, immediately after the copyright notices, a license
220 notice giving the public permission to use the Modified Version
221 under the terms of this License, in the form shown in the
224 7. Preserve in that license notice the full lists of Invariant
225 Sections and required Cover Texts given in the Document's
228 8. Include an unaltered copy of this License.
230 9. Preserve the section Entitled "History", Preserve its Title, and
231 add to it an item stating at least the title, year, new authors,
232 and publisher of the Modified Version as given on the Title
233 Page. If there is no section Entitled "History" in the Document,
234 create one stating the title, year, authors, and publisher of
235 the Document as given on its Title Page, then add an item
236 describing the Modified Version as stated in the previous
239 10. Preserve the network location, if any, given in the Document
240 for public access to a Transparent copy of the Document, and
241 likewise the network locations given in the Document for
242 previous versions it was based on. These may be placed in the
243 "History" section. You may omit a network location for a work
244 that was published at least four years before the Document
245 itself, or if the original publisher of the version it refers
248 11. For any section Entitled "Acknowledgements" or "Dedications",
249 Preserve the Title of the section, and preserve in the section
250 all the substance and tone of each of the contributor
251 acknowledgements and/or dedications given therein.
253 12. Preserve all the Invariant Sections of the Document, unaltered
254 in their text and in their titles. Section numbers or the
255 equivalent are not considered part of the section titles.
257 13. Delete any section Entitled "Endorsements". Such a section may
258 not be included in the Modified Version.
260 14. Do not retitle any existing section to be Entitled
261 "Endorsements" or to conflict in title with any Invariant
264 15. Preserve any Warranty Disclaimers.
266 If the Modified Version includes new front-matter sections or
267 appendices that qualify as Secondary Sections and contain no material
268 copied from the Document, you may at your option designate some or all
269 of these sections as invariant. To do this, add their titles to the
270 list of Invariant Sections in the Modified Version's license notice.
271 These titles must be distinct from any other section titles.
273 You may add a section Entitled "Endorsements", provided it contains
274 nothing but endorsements of your Modified Version by various
275 parties---for example, statements of peer review or that the text has
276 been approved by an organization as the authoritative definition of a
279 You may add a passage of up to five words as a Front-Cover Text, and a
280 passage of up to 25 words as a Back-Cover Text, to the end of the list
281 of Cover Texts in the Modified Version. Only one passage of
282 Front-Cover Text and one of Back-Cover Text may be added by (or
283 through arrangements made by) any one entity. If the Document already
284 includes a cover text for the same cover, previously added by you or
285 by arrangement made by the same entity you are acting on behalf of,
286 you may not add another; but you may replace the old one, on explicit
287 permission from the previous publisher that added the old one.
289 The author(s) and publisher(s) of the Document do not by this License
290 give permission to use their names for publicity for or to assert or
291 imply endorsement of any Modified Version.
293 5. COMBINING DOCUMENTS
295 You may combine the Document with other documents released under
296 this License, under the terms defined in section 4 above for
297 modified versions, provided that you include in the combination all
298 of the Invariant Sections of all of the original documents,
299 unmodified, and list them all as Invariant Sections of your
300 combined work in its license notice, and that you preserve all
301 their Warranty Disclaimers.
303 The combined work need only contain one copy of this License, and
304 multiple identical Invariant Sections may be replaced with a single
305 copy. If there are multiple Invariant Sections with the same name
306 but different contents, make the title of each such section unique
307 by adding at the end of it, in parentheses, the name of the
308 original author or publisher of that section if known, or else
309 a unique number. Make the same adjustment to the section titles in
310 the list of Invariant Sections in the license notice of the
313 In the combination, you must combine any sections Entitled
314 "History" in the various original documents, forming one section
315 Entitled "History"; likewise combine any sections Entitled
316 "Acknowledgements", and any sections Entitled "Dedications". You
317 must delete all sections Entitled "Endorsements."
319 6. COLLECTIONS OF DOCUMENTS
321 You may make a collection consisting of the Document and other
322 documents released under this License, and replace the individual
323 copies of this License in the various documents with a single copy
324 that is included in the collection, provided that you follow the
325 rules of this License for verbatim copying of each of the documents
326 in all other respects.
328 You may extract a single document from such a collection, and
329 distribute it individually under this License, provided you insert
330 a copy of this License into the extracted document, and follow this
331 License in all other respects regarding verbatim copying of that
334 7. AGGREGATION WITH INDEPENDENT WORKS
336 A compilation of the Document or its derivatives with other
337 separate and independent documents or works, in or on a volume of
338 a storage or distribution medium, is called an "aggregate" if the
339 copyright resulting from the compilation is not used to limit the
340 legal rights of the compilation's users beyond what the individual
341 works permit. When the Document is included in an aggregate, this
342 License does not apply to the other works in the aggregate which
343 are not themselves derivative works of the Document.
345 If the Cover Text requirement of section 3 is applicable to these
346 copies of the Document, then if the Document is less than one half
347 of the entire aggregate, the Document's Cover Texts may be placed
348 on covers that bracket the Document within the aggregate, or the
349 electronic equivalent of covers if the Document is in electronic
350 form. Otherwise they must appear on printed covers that bracket
355 Translation is considered a kind of modification, so you may
356 distribute translations of the Document under the terms of
357 section 4. Replacing Invariant Sections with translations requires
358 special permission from their copyright holders, but you may
359 include translations of some or all Invariant Sections in addition
360 to the original versions of these Invariant Sections. You may
361 include a translation of this License, and all the license notices
362 in the Document, and any Warranty Disclaimers, provided that you
363 also include the original English version of this License and the
364 original versions of those notices and disclaimers. In case of
365 a disagreement between the translation and the original version of
366 this License or a notice or disclaimer, the original version will
369 If a section in the Document is Entitled "Acknowledgements",
370 "Dedications", or "History", the requirement (section 4) to
371 Preserve its Title (section 1) will typically require changing the
376 You may not copy, modify, sublicense, or distribute the Document
377 except as expressly provided under this License. Any attempt
378 otherwise to copy, modify, sublicense, or distribute it is void,
379 and will automatically terminate your rights under this License.
381 However, if you cease all violation of this License, then your
382 license from a particular copyright holder is reinstated (a)
383 provisionally, unless and until the copyright holder explicitly and
384 finally terminates your license, and (b) permanently, if the
385 copyright holder fails to notify you of the violation by some
386 reasonable means prior to 60 days after the cessation.
388 Moreover, your license from a particular copyright holder is
389 reinstated permanently if the copyright holder notifies you of the
390 violation by some reasonable means, this is the first time you have
391 received notice of violation of this License (for any work) from
392 that copyright holder, and you cure the violation prior to 30 days
393 after your receipt of the notice.
395 Termination of your rights under this section does not terminate
396 the licenses of parties who have received copies or rights from you
397 under this License. If your rights have been terminated and not
398 permanently reinstated, receipt of a copy of some or all of the
399 same material does not give you any rights to use it.
401 10. FUTURE REVISIONS OF THIS LICENSE
403 The Free Software Foundation may publish new, revised versions of
404 the GNU Free Documentation License from time to time. Such new
405 versions will be similar in spirit to the present version, but may
406 differ in detail to address new problems or concerns. See
407 http://www.gnu.org/copyleft/.
409 Each version of the License is given a distinguishing version
410 number. If the Document specifies that a particular numbered
411 version of this License "or any later version" applies to it, you
412 have the option of following the terms and conditions either of
413 that specified version or of any later version that has been
414 published (not as a draft) by the Free Software Foundation. If
415 the Document does not specify a version number of this License,
416 you may choose any version ever published (not as a draft) by the
417 Free Software Foundation. If the Document specifies that a proxy
418 can decide which future versions of this License can be used, that
419 proxy's public statement of acceptance of a version permanently
420 authorizes you to choose that version for the Document.
424 "Massive Multiauthor Collaboration Site" (or "MMC Site") means any
425 World Wide Web server that publishes copyrightable works and also
426 provides prominent facilities for anybody to edit those works.
427 A public wiki that anybody can edit is an example of such
428 a server. A "Massive Multiauthor Collaboration" (or "MMC")
429 contained in the site means any set of copyrightable works thus
430 published on the MMC site.
432 "CC-BY-SA" means the Creative Commons Attribution-Share Alike 3.0
433 license published by Creative Commons Corporation,
434 a not-for-profit corporation with a principal place of business in
435 San Francisco, California, as well as future copyleft versions of
436 that license published by that same organization.
438 "Incorporate" means to publish or republish a Document, in whole
439 or in part, as part of another Document.
441 An MMC is "eligible for relicensing" if it is licensed under this
442 License, and if all works that were first published under this
443 License somewhere other than this MMC, and subsequently
444 incorporated in whole or in part into the MMC, (1) had no cover
445 texts or invariant sections, and (2) were thus incorporated prior
448 The operator of an MMC Site may republish an MMC contained in the
449 site under CC-BY-SA on the same site at any time before August 1,
450 2009, provided the MMC is eligible for relicensing.
454 * ADDENDUM: How to use this License for your documents
459 To use this License in a document you have written, include a copy of
460 the License in the document and put the following copyright and
461 license notices just after the title page:
464 Copyright (C) YEAR YOUR NAME.
465 Permission is granted to copy, distribute and/or modify this document
466 under the terms of the GNU Free Documentation License, Version 1.3
467 or any later version published by the Free Software Foundation;
468 with no Invariant Sections, no Front-Cover Texts, and no Back-Cover
469 Texts. A copy of the license is included in the section entitled ``GNU
470 Free Documentation License''.
473 If you have Invariant Sections, Front-Cover Texts and Back-Cover Texts,
474 replace the "with...Texts."\nbsp{}line with this:
477 with the Invariant Sections being LIST THEIR TITLES, with
478 the Front-Cover Texts being LIST, and with the Back-Cover Texts
482 If you have Invariant Sections without Cover Texts, or some other
483 combination of the three, merge those two alternatives to suit the
486 If your document contains nontrivial examples of program code, we
487 recommend releasing these examples in parallel under your choice of
488 free software license, such as the GNU General Public License, to
489 permit their use in free software.