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