1 2 3The LaTeX Project Public License 4=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=- 5 6LPPL Version 1.2 1999-09-03 7 8Copyright 1999 LaTeX3 Project 9 Everyone is allowed to distribute verbatim copies of this 10 license document, but modification of it is not allowed. 11 12 13PREAMBLE 14======== 15 16The LaTeX Project Public License (LPPL) is the license under which the 17base LaTeX distribution is distributed. 18 19You may use this license for any program that you have written and wish 20to distribute. This license may be particularly suitable if your 21program is TeX-related (such as a LaTeX package), but you may use it 22even if your program is unrelated to TeX. The section `WHETHER AND HOW 23TO DISTRIBUTE PROGRAMS UNDER THIS LICENSE`, below, gives instructions, 24examples, and recommendations for authors who are considering 25distributing their programs under this license. 26 27In this license document, `The Program` refers to any program 28distributed under this license. 29 30This license gives conditions under which The Program may be distributed 31and conditions under which modified versions of The Program may be 32distributed. Individual files of The Program may bear supplementary 33and/or superseding conditions on modification of themselves and on the 34distribution of modified versions of themselves, but *no* file of The 35Program may bear supplementary or superseding conditions on the 36distribution of an unmodified copy of the file. A distributor wishing 37to distribute a complete, unmodified copy of The Program therefore 38needs to check the conditions only in this license and nowhere else. 39 40Activities other than distribution and/or modification of The Program 41are not covered by this license; they are outside its scope. In 42particular, the act of running The Program is not restricted. 43 44We, the LaTeX3 Project, believe that the conditions below give you 45the freedom to make and distribute modified versions of The Program 46that conform with whatever technical specifications you wish while 47maintaining the availability, integrity, and reliability of 48The Program. If you do not see how to achieve your goal while 49meeting these conditions, then read the document `cfgguide.tex` 50in the base LaTeX distribution for suggestions. 51 52 53CONDITIONS ON DISTRIBUTION AND MODIFICATION 54=========================================== 55 56You may distribute a complete, unmodified copy of The Program. 57Distribution of only part of The Program is not allowed. 58 59You may not modify in any way a file of The Program that bears a legal 60notice forbidding modification of that file. 61 62You may distribute a modified file of The Program if, and only if, the 63following eight conditions are met: 64 65 1. You must meet any additional conditions borne by the file on the 66 distribution of a modified version of the file as described below 67 in the subsection `Additional Conditions on Individual Files of 68 The Program`. 69 70 2. If the file is a LaTeX software file, then you must meet any 71 applicable additional conditions on the distribution of a modified 72 version of the file that are described below in the subsection 73 `Additional Conditions on LaTeX Software Files`. 74 75 3. You must not distribute the modified file with the filename of the 76 original file. 77 78 4. In the modified file, you must acknowledge the authorship and 79 name of the original file, and the name (if any) of the program 80 which contains it. 81 82 5. You must change any identification string in the file to indicate 83 clearly that the modified file is not part of The Program. 84 85 6. You must change any addresses in the modified file for the 86 reporting of errors in the file or in The Program generally to 87 ensure that reports for files no longer maintained by the original 88 maintainers will be directed to the maintainers of the modified 89 files. 90 91 7. You must distribute the modified file under a license that forbids 92 distribution both of the modified file and of any files derived 93 from the modified file with the filename of the original file. 94 95 8. You must do either (A) or (B): 96 97 (A) distribute a copy of The Program (that is, a complete, 98 unmodified copy of The Program) together with the modified 99 file; if your distribution of the modified file is made by 100 offering access to copy the modified file from a designated 101 place, then offering equivalent access to copy The Program 102 from the same place meets this condition, even though third 103 parties are not compelled to copy The Program along with the 104 modified file; 105 106 (B) provide to those who receive the modified file information 107 that is sufficient for them to obtain a copy of The Program; 108 for example, you may provide a Uniform Resource Locator (URL) 109 for a site that you expect will provide them with a copy of 110 The Program free of charge (either the version from which 111 your modification is derived, or perhaps a later version). 112 113Note that in the above, `distribution` of a file means making the 114file available to others by any means. This includes, for instance, 115installing the file on any machine in such a way that the file is 116accessible by users other than yourself. `Modification` of a file 117means any procedure that produces a derivative file under any 118applicable law -- that is, a file containing the original file or 119a significant portion of it, either verbatim or with modifications 120and/or translated into another language. 121 122Changing the name of a file (other than as necessitated by the file 123conventions of the target file systems) is considered to be a 124modification of the file. 125 126The distribution conditions in this license do not have to be 127applied to files that have been modified in accordance with the 128above conditions. Note, however, that Condition 7. does apply to 129any such modified file. 130 131The conditions above are not intended to prohibit, and hence do not 132apply to, the updating, by any method, of a file so that it becomes 133identical to the latest version of that file of The Program. 134 135 136 137A Recommendation on Modification Without Distribution 138----------------------------------------------------- 139 140It is wise never to modify a file of The Program, even for your own 141personal use, without also meeting the above eight conditions for 142distributing the modified file. While you might intend that such 143modified files will never be distributed, often this will happen by 144accident -- you may forget that you have modified the file; or it may 145not occur to you when allowing others to access the modified file 146that you are thus distributing it and violating the conditions of 147this license. It is usually in your best interest to keep your copy 148of The Program identical with the public one. Many programs provide 149ways to control the behavior of that program without altering its 150licensed files. 151 152 153Additional Conditions on Individual Files of The Program 154-------------------------------------------------------- 155 156An individual file of The Program may bear additional conditions that 157supplement and/or supersede the conditions in this license if, and only 158if, such additional conditions exclusively concern modification of the 159file or distribution of a modified version of the file. The conditions 160on individual files of The Program therefore may differ only with 161respect to the kind and extent of modification of those files that 162is allowed, and with respect to the distribution of modified versions 163of those files. 164 165 166Additional Conditions on LaTeX Software Files 167--------------------------------------------- 168 169If a file of The Program is intended to be used with LaTeX (that is, 170if it is a LaTeX software file), then the following additional 171conditions, which supplement and/or supersede the conditions 172above, apply to the file according to its filename extension: 173 174 - You may not modify any file with filename extension `.ins` since 175 these are installation files containing the legal notices that are 176 placed in the files they generate. 177 178 - You may distribute modified versions of files with filename 179 extension `.fd` (LaTeX font definition files) under the standard 180 conditions of the LPPL as described above. You may also distribute 181 such modified LaTeX font definition files with their original names 182 provided that: 183 (1) the only changes to the original files either enable use of 184 available fonts or prevent attempts to access unavailable fonts; 185 (2) you also distribute the original, unmodified files (TeX input 186 paths can be used to control which set of LaTeX font definition 187 files is actually used by TeX). 188 189 - You may distribute modified versions of files with filename 190 extension `.cfg` (configuration files) with their original names. 191 The Program may (and usually will) specify the range of commands 192 that are allowed in a particular configuration file. 193 194Because of portability and exchangeability issues in LaTeX software, 195The LaTeX3 Project deprecates the distribution of modified versions of 196components of LaTeX or of generally available contributed code for them, 197but such distribution can meet the conditions of this license. 198 199 200NO WARRANTY 201=========== 202 203There is no warranty for The Program. Except when otherwise stated in 204writing, The Copyright Holder provides The Program `as is`, without 205warranty of any kind, either expressed or implied, including, but not 206limited to, the implied warranties of merchantability and fitness for 207a particular purpose. The entire risk as to the quality and performance 208of The Program is with you. Should The Program prove defective, you 209assume the cost of all necessary servicing, repair, or correction. 210 211In no event unless agreed to in writing will The Copyright Holder, or 212any author named in the files of The Program, or any other party who may 213distribute and/or modify The Program as permitted above, be liable to 214you for damages, including any general, special, incidental or 215consequential damages arising out of any use of The Program or out of 216inability to use The Program (including, but not limited to, loss of 217data, data being rendered inaccurate, or losses sustained by anyone as 218a result of any failure of The Program to operate with any other 219programs), even if The Copyright Holder or said author or said other 220party has been advised of the possibility of such damages. 221 222 223WHETHER AND HOW TO DISTRIBUTE PROGRAMS UNDER THIS LICENSE 224========================================================= 225 226This section contains important instructions, examples, and 227recommendations for authors who are considering distributing their 228programs under this license. These authors are addressed as `you` in 229this section. 230 231 232Choosing This License or Another License 233---------------------------------------- 234 235If for any part of your program you want or need to use *distribution* 236conditions that differ from those in this license, then do not refer to 237this license anywhere in your program but instead distribute your 238program under a different license. You may use the text of this license 239as a model for your own license, but your license should not refer to 240the LPPL or otherwise give the impression that your program is 241distributed under the LPPL. 242 243The document `modguide.tex` in the base LaTeX distribution explains 244the motivation behind the conditions of this license. It explains, 245for example, why distributing LaTeX under the GNU General Public 246License (GPL) was considered inappropriate. Even if your program is 247unrelated to LaTeX, the discussion in `modguide.tex` may still be 248relevant, and authors intending to distribute their programs under any 249license are encouraged to read it. 250 251 252How to Use This License 253----------------------- 254 255To use this license, place in each of the files of your program both 256an explicit copyright notice including your name and the year and also 257a statement that the distribution and/or modification of the file is 258constrained by the conditions in this license. 259 260Here is an example of such a notice and statement: 261 262 %% pig.dtx 263 %% Copyright 2001 M. Y. Name 264 % 265 % This program may be distributed and/or modified under the 266 % conditions of the LaTeX Project Public License, either version 1.2 267 % of this license or (at your option) any later version. 268 % The latest version of this license is in 269 % http://www.latex-project.org/lppl.txt 270 % and version 1.2 or later is part of all distributions of LaTeX 271 % version 1999/12/01 or later. 272 % 273 % This program consists of the files pig.dtx and pig.ins 274 275Given such a notice and statement in a file, the conditions given in 276this license document would apply, with `The Program` referring to the 277two files `pig.dtx` and `pig.ins`, and `The Copyright Holder` referring 278to the person `M. Y. Name`. 279 280 281Important Recommendations 282------------------------- 283 284 Defining What Constitutes The Program 285 286 The LPPL requires that distributions of The Program contain all the 287 files of The Program. It is therefore important that you provide a 288 way for the licensee to determine which files constitute The Program. 289 This could, for example, be achieved by explicitly listing all the 290 files of The Program near the copyright notice of each file or by 291 using a line like 292 293 % This program consists of all files listed in manifest.txt. 294 295 in that place. In the absence of an unequivocal list it might be 296 impossible for the licensee to determine what is considered by you 297 to comprise The Program. 298 299 Noting Exceptional Files 300 301 If The Program contains any files bearing additional conditions on 302 modification, or on distribution of modified versions, of those 303 files (other than those listed in `Additional Conditions on LaTeX 304 Software Files`), then it is recommended that The Program contain a 305 prominent file that defines the exceptional conditions, and either 306 lists the exceptional files or defines one or more categories of 307 exceptional files. 308 309 Files containing the text of a license (such as this file) are 310 often examples of files bearing more restrictive conditions on 311 modification. LaTeX configuration files (with filename extension 312 `.cfg`) are examples of files bearing less restrictive conditions 313 on the distribution of a modified version of the file. The 314 additional conditions on LaTeX software given above are examples 315 of declaring a category of files bearing exceptional additional 316 conditions. 317 318 319 320 321