1@c The GNU Free Documentation License. 2@center Version 1.2, November 2002 3 4@c This file is intended to be included within another document, 5@c hence no sectioning command or @node. 6 7@display 8Copyright @copyright{} 2000,2001,2002 Free Software Foundation, Inc. 951 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA 10 11Everyone is permitted to copy and distribute verbatim copies 12of this license document, but changing it is not allowed. 13@end display 14 15@enumerate 0 16@item 17PREAMBLE 18 19The purpose of this License is to make a manual, textbook, or other 20functional and useful document @dfn{free} in the sense of freedom: to 21assure everyone the effective freedom to copy and redistribute it, 22with or without modifying it, either commercially or noncommercially. 23Secondarily, this License preserves for the author and publisher a way 24to get credit for their work, while not being considered responsible 25for modifications made by others. 26 27This License is a kind of ``copyleft'', which means that derivative 28works of the document must themselves be free in the same sense. It 29complements the GNU General Public License, which is a copyleft 30license designed for free software. 31 32We have designed this License in order to use it for manuals for free 33software, because free software needs free documentation: a free 34program should come with manuals providing the same freedoms that the 35software does. But this License is not limited to software manuals; 36it can be used for any textual work, regardless of subject matter or 37whether it is published as a printed book. We recommend this License 38principally for works whose purpose is instruction or reference. 39 40@item 41APPLICABILITY AND DEFINITIONS 42 43This License applies to any manual or other work, in any medium, that 44contains a notice placed by the copyright holder saying it can be 45distributed under the terms of this License. Such a notice grants a 46world-wide, royalty-free license, unlimited in duration, to use that 47work under the conditions stated herein. The ``Document'', below, 48refers to any such manual or work. Any member of the public is a 49licensee, and is addressed as ``you''. You accept the license if you 50copy, modify or distribute the work in a way requiring permission 51under copyright law. 52 53A ``Modified Version'' of the Document means any work containing the 54Document or a portion of it, either copied verbatim, or with 55modifications and/or translated into another language. 56 57A ``Secondary Section'' is a named appendix or a front-matter section 58of the Document that deals exclusively with the relationship of the 59publishers or authors of the Document to the Document's overall 60subject (or to related matters) and contains nothing that could fall 61directly within that overall subject. (Thus, if the Document is in 62part a textbook of mathematics, a Secondary Section may not explain 63any mathematics.) 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A copy that is not ``Transparent'' is called ``Opaque''. 93 94Examples of suitable formats for Transparent copies include plain 95@sc{ascii} without markup, Texinfo input format, La@TeX{} input 96format, @acronym{SGML} or @acronym{XML} using a publicly available 97@acronym{DTD}, and standard-conforming simple @acronym{HTML}, 98PostScript or @acronym{PDF} designed for human modification. Examples 99of transparent image formats include @acronym{PNG}, @acronym{XCF} and 100@acronym{JPG}. 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These Warranty 124Disclaimers are considered to be included by reference in this 125License, but only as regards disclaiming warranties: any other 126implication that these Warranty Disclaimers may have is void and has 127no effect on the meaning of this License. 128 129@item 130VERBATIM COPYING 131 132You may copy and distribute the Document in any medium, either 133commercially or noncommercially, provided that this License, the 134copyright notices, and the license notice saying this License applies 135to the Document are reproduced in all copies, and that you add no other 136conditions whatsoever to those of this License. You may not use 137technical measures to obstruct or control the reading or further 138copying of the copies you make or distribute. However, you may accept 139compensation in exchange for copies. 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You may add other material on the covers in addition. 157Copying with changes limited to the covers, as long as they preserve 158the title of the Document and satisfy these conditions, can be treated 159as verbatim copying in other respects. 160 161If the required texts for either cover are too voluminous to fit 162legibly, you should put the first ones listed (as many as fit 163reasonably) on the actual cover, and continue the rest onto adjacent 164pages. 165 166If you publish or distribute Opaque copies of the Document numbering 167more than 100, you must either include a machine-readable Transparent 168copy along with each Opaque copy, or state in or with each Opaque copy 169a computer-network location from which the general network-using 170public has access to download using public-standard network protocols 171a complete Transparent copy of the Document, free of added material. 172If you use the latter option, you must take reasonably prudent steps, 173when you begin distribution of Opaque copies in quantity, to ensure 174that this Transparent copy will remain thus accessible at the stated 175location until at least one year after the last time you distribute an 176Opaque copy (directly or through your agents or retailers) of that 177edition to the public. 178 179It is requested, but not required, that you contact the authors of the 180Document well before redistributing any large number of copies, to give 181them a chance to provide you with an updated version of the Document. 182 183@item 184MODIFICATIONS 185 186You may copy and distribute a Modified Version of the Document under 187the conditions of sections 2 and 3 above, provided that you release 188the Modified Version under precisely this License, with the Modified 189Version filling the role of the Document, thus licensing distribution 190and modification of the Modified Version to whoever possesses a copy 191of it. In addition, you must do these things in the Modified Version: 192 193@enumerate A 194@item 195Use in the Title Page (and on the covers, if any) a title distinct 196from that of the Document, and from those of previous versions 197(which should, if there were any, be listed in the History section 198of the Document). You may use the same title as a previous version 199if the original publisher of that version gives permission. 200 201@item 202List on the Title Page, as authors, one or more persons or entities 203responsible for authorship of the modifications in the Modified 204Version, together with at least five of the principal authors of the 205Document (all of its principal authors, if it has fewer than five), 206unless they release you from this requirement. 207 208@item 209State on the Title page the name of the publisher of the 210Modified Version, as the publisher. 211 212@item 213Preserve all the copyright notices of the Document. 214 215@item 216Add an appropriate copyright notice for your modifications 217adjacent to the other copyright notices. 218 219@item 220Include, immediately after the copyright notices, a license notice 221giving the public permission to use the Modified Version under the 222terms of this License, in the form shown in the Addendum below. 223 224@item 225Preserve in that license notice the full lists of Invariant Sections 226and required Cover Texts given in the Document's license notice. 227 228@item 229Include an unaltered copy of this License. 230 231@item 232Preserve the section Entitled ``History'', Preserve its Title, and add 233to it an item stating at least the title, year, new authors, and 234publisher of the Modified Version as given on the Title Page. If 235there is no section Entitled ``History'' in the Document, create one 236stating the title, year, authors, and publisher of the Document as 237given on its Title Page, then add an item describing the Modified 238Version as stated in the previous sentence. 239 240@item 241Preserve the network location, if any, given in the Document for 242public access to a Transparent copy of the Document, and likewise 243the network locations given in the Document for previous versions 244it was based on. These may be placed in the ``History'' section. 245You may omit a network location for a work that was published at 246least four years before the Document itself, or if the original 247publisher of the version it refers to gives permission. 248 249@item 250For any section Entitled ``Acknowledgements'' or ``Dedications'', Preserve 251the Title of the section, and preserve in the section all the 252substance and tone of each of the contributor acknowledgements and/or 253dedications given therein. 254 255@item 256Preserve all the Invariant Sections of the Document, 257unaltered in their text and in their titles. Section numbers 258or the equivalent are not considered part of the section titles. 259 260@item 261Delete any section Entitled ``Endorsements''. Such a section 262may not be included in the Modified Version. 263 264@item 265Do not retitle any existing section to be Entitled ``Endorsements'' or 266to conflict in title with any Invariant Section. 267 268@item 269Preserve any Warranty Disclaimers. 270@end enumerate 271 272If the Modified Version includes new front-matter sections or 273appendices that qualify as Secondary Sections and contain no material 274copied from the Document, you may at your option designate some or all 275of these sections as invariant. To do this, add their titles to the 276list of Invariant Sections in the Modified Version's license notice. 277These titles must be distinct from any other section titles. 278 279You may add a section Entitled ``Endorsements'', provided it contains 280nothing but endorsements of your Modified Version by various 281parties---for example, statements of peer review or that the text has 282been approved by an organization as the authoritative definition of a 283standard. 284 285You may add a passage of up to five words as a Front-Cover Text, and a 286passage of up to 25 words as a Back-Cover Text, to the end of the list 287of Cover Texts in the Modified Version. Only one passage of 288Front-Cover Text and one of Back-Cover Text may be added by (or 289through arrangements made by) any one entity. If the Document already 290includes a cover text for the same cover, previously added by you or 291by arrangement made by the same entity you are acting on behalf of, 292you may not add another; but you may replace the old one, on explicit 293permission from the previous publisher that added the old one. 294 295The author(s) and publisher(s) of the Document do not by this License 296give permission to use their names for publicity for or to assert or 297imply endorsement of any Modified Version. 298 299@item 300COMBINING DOCUMENTS 301 302You may combine the Document with other documents released under this 303License, under the terms defined in section 4 above for modified 304versions, provided that you include in the combination all of the 305Invariant Sections of all of the original documents, unmodified, and 306list them all as Invariant Sections of your combined work in its 307license notice, and that you preserve all their Warranty Disclaimers. 308 309The combined work need only contain one copy of this License, and 310multiple identical Invariant Sections may be replaced with a single 311copy. If there are multiple Invariant Sections with the same name but 312different contents, make the title of each such section unique by 313adding at the end of it, in parentheses, the name of the original 314author or publisher of that section if known, or else a unique number. 315Make the same adjustment to the section titles in the list of 316Invariant Sections in the license notice of the combined work. 317 318In the combination, you must combine any sections Entitled ``History'' 319in the various original documents, forming one section Entitled 320``History''; likewise combine any sections Entitled ``Acknowledgements'', 321and any sections Entitled ``Dedications''. You must delete all 322sections Entitled ``Endorsements.'' 323 324@item 325COLLECTIONS OF DOCUMENTS 326 327You may make a collection consisting of the Document and other documents 328released under this License, and replace the individual copies of this 329License in the various documents with a single copy that is included in 330the collection, provided that you follow the rules of this License for 331verbatim copying of each of the documents in all other respects. 332 333You may extract a single document from such a collection, and distribute 334it individually under this License, provided you insert a copy of this 335License into the extracted document, and follow this License in all 336other respects regarding verbatim copying of that document. 337 338@item 339AGGREGATION WITH INDEPENDENT WORKS 340 341A compilation of the Document or its derivatives with other separate 342and independent documents or works, in or on a volume of a storage or 343distribution medium, is called an ``aggregate'' if the copyright 344resulting from the compilation is not used to limit the legal rights 345of the compilation's users beyond what the individual works permit. 346When the Document is included in an aggregate, this License does not 347apply to the other works in the aggregate which are not themselves 348derivative works of the Document. 349 350If the Cover Text requirement of section 3 is applicable to these 351copies of the Document, then if the Document is less than one half of 352the entire aggregate, the Document's Cover Texts may be placed on 353covers that bracket the Document within the aggregate, or the 354electronic equivalent of covers if the Document is in electronic form. 355Otherwise they must appear on printed covers that bracket the whole 356aggregate. 357 358@item 359TRANSLATION 360 361Translation is considered a kind of modification, so you may 362distribute translations of the Document under the terms of section 4. 363Replacing Invariant Sections with translations requires special 364permission from their copyright holders, but you may include 365translations of some or all Invariant Sections in addition to the 366original versions of these Invariant Sections. You may include a 367translation of this License, and all the license notices in the 368Document, and any Warranty Disclaimers, provided that you also include 369the original English version of this License and the original versions 370of those notices and disclaimers. In case of a disagreement between 371the translation and the original version of this License or a notice 372or disclaimer, the original version will prevail. 373 374If a section in the Document is Entitled ``Acknowledgements'', 375``Dedications'', or ``History'', the requirement (section 4) to Preserve 376its Title (section 1) will typically require changing the actual 377title. 378 379@item 380TERMINATION 381 382You may not copy, modify, sublicense, or distribute the Document except 383as expressly provided for under this License. Any other attempt to 384copy, modify, sublicense or distribute the Document is void, and will 385automatically terminate your rights under this License. However, 386parties who have received copies, or rights, from you under this 387License will not have their licenses terminated so long as such 388parties remain in full compliance. 389 390@item 391FUTURE REVISIONS OF THIS LICENSE 392 393The Free Software Foundation may publish new, revised versions 394of the GNU Free Documentation License from time to time. Such new 395versions will be similar in spirit to the present version, but may 396differ in detail to address new problems or concerns. See 397@uref{https://www.gnu.org/copyleft/}. 398 399Each version of the License is given a distinguishing version number. 400If the Document specifies that a particular numbered version of this 401License ``or any later version'' applies to it, you have the option of 402following the terms and conditions either of that specified version or 403of any later version that has been published (not as a draft) by the 404Free Software Foundation. If the Document does not specify a version 405number of this License, you may choose any version ever published (not 406as a draft) by the Free Software Foundation. 407@end enumerate 408 409@page 410@heading ADDENDUM: How to use this License for your documents 411 412To use this License in a document you have written, include a copy of 413the License in the document and put the following copyright and 414license notices just after the title page: 415 416@smallexample 417@group 418 Copyright (C) @var{year} @var{your name}. 419 Permission is granted to copy, distribute and/or modify this document 420 under the terms of the GNU Free Documentation License, Version 1.2 421 or any later version published by the Free Software Foundation; 422 with no Invariant Sections, no Front-Cover Texts, and no Back-Cover 423 Texts. A copy of the license is included in the section entitled ``GNU 424 Free Documentation License''. 425@end group 426@end smallexample 427 428If you have Invariant Sections, Front-Cover Texts and Back-Cover Texts, 429replace the ``with@dots{}Texts.'' line with this: 430 431@smallexample 432@group 433 with the Invariant Sections being @var{list their titles}, with 434 the Front-Cover Texts being @var{list}, and with the Back-Cover Texts 435 being @var{list}. 436@end group 437@end smallexample 438 439If you have Invariant Sections without Cover Texts, or some other 440combination of the three, merge those two alternatives to suit the 441situation. 442 443If your document contains nontrivial examples of program code, we 444recommend releasing these examples in parallel under your choice of 445free software license, such as the GNU General Public License, 446to permit their use in free software. 447 448@c Local Variables: 449@c ispell-local-pdict: "ispell-dict" 450@c End: 451