1 GNU LESSER GENERAL PUBLIC LICENSE 2 Version 2.1, February 1999 3 4 Copyright 1991, 1999 Free Software Foundation, Inc. 5 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 6 Everyone is permitted to copy and distribute verbatim copies 7 of this license document, but changing it is not allowed. 8 9 [This is the first released version of the Lesser GPL. It also counts 10 as the successor of the GNU Library Public License, version 2, hence 11 the version number 2.1.] 12 13 Preamble 14 15 The licenses for most software are designed to take away your 16 freedom to share and change it. By contrast, the GNU General Public 17 Licenses are intended to guarantee your freedom to share and change 18 free software--to make sure the software is free for all its users. 19 20 This license, the Lesser General Public License, applies to some 21 specially designated software packages--typically libraries--of the 22 Free Software Foundation and other authors who decide to use it. You 23 can use it too, but we suggest you first think carefully about whether 24 this license or the ordinary General Public License is the better 25 strategy to use in any particular case, based on the explanations below. 26 27 When we speak of free software, we are referring to freedom of use, 28 not price. Our General Public Licenses are designed to make sure that 29 you have the freedom to distribute copies of free software (and charge 30 for this service if you wish); that you receive source code or can get 31 it if you want it; that you can change the software and use pieces of 32 it in new free programs; and that you are informed that you can do 33 these things. 34 35 To protect your rights, we need to make restrictions that forbid 36 distributors to deny you these rights or to ask you to surrender these 37 rights. These restrictions translate to certain responsibilities for 38 you if you distribute copies of the library or if you modify it. 39 40 For example, if you distribute copies of the library, whether gratis 41 or for a fee, you must give the recipients all the rights that we gave 42 you. You must make sure that they, too, receive or can get the source 43 code. If you link other code with the library, you must provide 44 complete object files to the recipients, so that they can relink them 45 with the library after making changes to the library and recompiling 46 it. And you must show them these terms so they know their rights. 47 48 We protect your rights with a two-step method: (1) we copyright the 49 library, and (2) we offer you this license, which gives you legal 50 permission to copy, distribute and/or modify the library. 51 52 To protect each distributor, we want to make it very clear that 53 there is no warranty for the free library. Also, if the library is 54 modified by someone else and passed on, the recipients should know 55 that what they have is not the original version, so that the original 56 author's reputation will not be affected by problems that might be 57 introduced by others. 58 60 Finally, software patents pose a constant threat to the existence of 61 any free program. We wish to make sure that a company cannot 62 effectively restrict the users of a free program by obtaining a 63 restrictive license from a patent holder. Therefore, we insist that 64 any patent license obtained for a version of the library must be 65 consistent with the full freedom of use specified in this license. 66 67 Most GNU software, including some libraries, is covered by the 68 ordinary GNU General Public License. This license, the GNU Lesser 69 General Public License, applies to certain designated libraries, and 70 is quite different from the ordinary General Public License. We use 71 this license for certain libraries in order to permit linking those 72 libraries into non-free programs. 73 74 When a program is linked with a library, whether statically or using 75 a shared library, the combination of the two is legally speaking a 76 combined work, a derivative of the original library. The ordinary 77 General Public License therefore permits such linking only if the 78 entire combination fits its criteria of freedom. The Lesser General 79 Public License permits more lax criteria for linking other code with 80 the library. 81 82 We call this license the "Lesser" General Public License because it 83 does Less to protect the user's freedom than the ordinary General 84 Public License. It also provides other free software developers Less 85 of an advantage over competing non-free programs. These disadvantages 86 are the reason we use the ordinary General Public License for many 87 libraries. However, the Lesser license provides advantages in certain 88 special circumstances. 89 90 For example, on rare occasions, there may be a special need to 91 encourage the widest possible use of a certain library, so that it becomes 92 a de-facto standard. To achieve this, non-free programs must be 93 allowed to use the library. A more frequent case is that a free 94 library does the same job as widely used non-free libraries. In this 95 case, there is little to gain by limiting the free library to free 96 software only, so we use the Lesser General Public License. 97 98 In other cases, permission to use a particular library in non-free 99 programs enables a greater number of people to use a large body of 100 free software. For example, permission to use the GNU C Library in 101 non-free programs enables many more people to use the whole GNU 102 operating system, as well as its variant, the GNU/Linux operating 103 system. 104 105 Although the Lesser General Public License is Less protective of the 106 users' freedom, it does ensure that the user of a program that is 107 linked with the Library has the freedom and the wherewithal to run 108 that program using a modified version of the Library. 109 110 The precise terms and conditions for copying, distribution and 111 modification follow. Pay close attention to the difference between a 112 "work based on the library" and a "work that uses the library". The 113 former contains code derived from the library, whereas the latter must 114 be combined with the library in order to run. 115 117 GNU LESSER GENERAL PUBLIC LICENSE 118 TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION 119 120 0. This License Agreement applies to any software library or other 121 program which contains a notice placed by the copyright holder or 122 other authorized party saying it may be distributed under the terms of 123 this Lesser General Public License (also called "this License"). 124 Each licensee is addressed as "you". 125 126 A "library" means a collection of software functions and/or data 127 prepared so as to be conveniently linked with application programs 128 (which use some of those functions and data) to form executables. 129 130 The "Library", below, refers to any such software library or work 131 which has been distributed under these terms. A "work based on the 132 Library" means either the Library or any derivative work under 133 copyright law: that is to say, a work containing the Library or a 134 portion of it, either verbatim or with modifications and/or translated 135 straightforwardly into another language. (Hereinafter, translation is 136 included without limitation in the term "modification".) 137 138 "Source code" for a work means the preferred form of the work for 139 making modifications to it. For a library, complete source code means 140 all the source code for all modules it contains, plus any associated 141 interface definition files, plus the scripts used to control compilation 142 and installation of the library. 143 144 Activities other than copying, distribution and modification are not 145 covered by this License; they are outside its scope. The act of 146 running a program using the Library is not restricted, and output from 147 such a program is covered only if its contents constitute a work based 148 on the Library (independent of the use of the Library in a tool for 149 writing it). Whether that is true depends on what the Library does 150 and what the program that uses the Library does. 151 152 1. You may copy and distribute verbatim copies of the Library's 153 complete source code as you receive it, in any medium, provided that 154 you conspicuously and appropriately publish on each copy an 155 appropriate copyright notice and disclaimer of warranty; keep intact 156 all the notices that refer to this License and to the absence of any 157 warranty; and distribute a copy of this License along with the 158 Library. 159 160 You may charge a fee for the physical act of transferring a copy, 161 and you may at your option offer warranty protection in exchange for a 162 fee. 163 165 2. You may modify your copy or copies of the Library or any portion 166 of it, thus forming a work based on the Library, and copy and 167 distribute such modifications or work under the terms of Section 1 168 above, provided that you also meet all of these conditions: 169 170 a) The modified work must itself be a software library. 171 172 b) You must cause the files modified to carry prominent notices 173 stating that you changed the files and the date of any change. 174 175 c) You must cause the whole of the work to be licensed at no 176 charge to all third parties under the terms of this License. 177 178 d) If a facility in the modified Library refers to a function or a 179 table of data to be supplied by an application program that uses 180 the facility, other than as an argument passed when the facility 181 is invoked, then you must make a good faith effort to ensure that, 182 in the event an application does not supply such function or 183 table, the facility still operates, and performs whatever part of 184 its purpose remains meaningful. 185 186 (For example, a function in a library to compute square roots has 187 a purpose that is entirely well-defined independent of the 188 application. Therefore, Subsection 2d requires that any 189 application-supplied function or table used by this function must 190 be optional: if the application does not supply it, the square 191 root function must still compute square roots.) 192 193 These requirements apply to the modified work as a whole. If 194 identifiable sections of that work are not derived from the Library, 195 and can be reasonably considered independent and separate works in 196 themselves, then this License, and its terms, do not apply to those 197 sections when you distribute them as separate works. But when you 198 distribute the same sections as part of a whole which is a work based 199 on the Library, the distribution of the whole must be on the terms of 200 this License, whose permissions for other licensees extend to the 201 entire whole, and thus to each and every part regardless of who wrote 202 it. 203 204 Thus, it is not the intent of this section to claim rights or contest 205 your rights to work written entirely by you; rather, the intent is to 206 exercise the right to control the distribution of derivative or 207 collective works based on the Library. 208 209 In addition, mere aggregation of another work not based on the Library 210 with the Library (or with a work based on the Library) on a volume of 211 a storage or distribution medium does not bring the other work under 212 the scope of this License. 213 214 3. You may opt to apply the terms of the ordinary GNU General Public 215 License instead of this License to a given copy of the Library. To do 216 this, you must alter all the notices that refer to this License, so 217 that they refer to the ordinary GNU General Public License, version 2, 218 instead of to this License. (If a newer version than version 2 of the 219 ordinary GNU General Public License has appeared, then you can specify 220 that version instead if you wish.) Do not make any other change in 221 these notices. 222 224 Once this change is made in a given copy, it is irreversible for 225 that copy, so the ordinary GNU General Public License applies to all 226 subsequent copies and derivative works made from that copy. 227 228 This option is useful when you wish to copy part of the code of 229 the Library into a program that is not a library. 230 231 4. You may copy and distribute the Library (or a portion or 232 derivative of it, under Section 2) in object code or executable form 233 under the terms of Sections 1 and 2 above provided that you accompany 234 it with the complete corresponding machine-readable source code, which 235 must be distributed under the terms of Sections 1 and 2 above on a 236 medium customarily used for software interchange. 237 238 If distribution of object code is made by offering access to copy 239 from a designated place, then offering equivalent access to copy the 240 source code from the same place satisfies the requirement to 241 distribute the source code, even though third parties are not 242 compelled to copy the source along with the object code. 243 244 5. A program that contains no derivative of any portion of the 245 Library, but is designed to work with the Library by being compiled or 246 linked with it, is called a "work that uses the Library". Such a 247 work, in isolation, is not a derivative work of the Library, and 248 therefore falls outside the scope of this License. 249 250 However, linking a "work that uses the Library" with the Library 251 creates an executable that is a derivative of the Library (because it 252 contains portions of the Library), rather than a "work that uses the 253 library". The executable is therefore covered by this License. 254 Section 6 states terms for distribution of such executables. 255 256 When a "work that uses the Library" uses material from a header file 257 that is part of the Library, the object code for the work may be a 258 derivative work of the Library even though the source code is not. 259 Whether this is true is especially significant if the work can be 260 linked without the Library, or if the work is itself a library. The 261 threshold for this to be true is not precisely defined by law. 262 263 If such an object file uses only numerical parameters, data 264 structure layouts and accessors, and small macros and small inline 265 functions (ten lines or less in length), then the use of the object 266 file is unrestricted, regardless of whether it is legally a derivative 267 work. (Executables containing this object code plus portions of the 268 Library will still fall under Section 6.) 269 270 Otherwise, if the work is a derivative of the Library, you may 271 distribute the object code for the work under the terms of Section 6. 272 Any executables containing that work also fall under Section 6, 273 whether or not they are linked directly with the Library itself. 274 276 6. As an exception to the Sections above, you may also combine or 277 link a "work that uses the Library" with the Library to produce a 278 work containing portions of the Library, and distribute that work 279 under terms of your choice, provided that the terms permit 280 modification of the work for the customer's own use and reverse 281 engineering for debugging such modifications. 282 283 You must give prominent notice with each copy of the work that the 284 Library is used in it and that the Library and its use are covered by 285 this License. You must supply a copy of this License. If the work 286 during execution displays copyright notices, you must include the 287 copyright notice for the Library among them, as well as a reference 288 directing the user to the copy of this License. Also, you must do one 289 of these things: 290 291 a) Accompany the work with the complete corresponding 292 machine-readable source code for the Library including whatever 293 changes were used in the work (which must be distributed under 294 Sections 1 and 2 above); and, if the work is an executable linked 295 with the Library, with the complete machine-readable "work that 296 uses the Library", as object code and/or source code, so that the 297 user can modify the Library and then relink to produce a modified 298 executable containing the modified Library. (It is understood 299 that the user who changes the contents of definitions files in the 300 Library will not necessarily be able to recompile the application 301 to use the modified definitions.) 302 303 b) Use a suitable shared library mechanism for linking with the 304 Library. A suitable mechanism is one that (1) uses at run time a 305 copy of the library already present on the user's computer system, 306 rather than copying library functions into the executable, and (2) 307 will operate properly with a modified version of the library, if 308 the user installs one, as long as the modified version is 309 interface-compatible with the version that the work was made with. 310 311 c) Accompany the work with a written offer, valid for at 312 least three years, to give the same user the materials 313 specified in Subsection 6a, above, for a charge no more 314 than the cost of performing this distribution. 315 316 d) If distribution of the work is made by offering access to copy 317 from a designated place, offer equivalent access to copy the above 318 specified materials from the same place. 319 320 e) Verify that the user has already received a copy of these 321 materials or that you have already sent this user a copy. 322 323 For an executable, the required form of the "work that uses the 324 Library" must include any data and utility programs needed for 325 reproducing the executable from it. However, as a special exception, 326 the materials to be distributed need not include anything that is 327 normally distributed (in either source or binary form) with the major 328 components (compiler, kernel, and so on) of the operating system on 329 which the executable runs, unless that component itself accompanies 330 the executable. 331 332 It may happen that this requirement contradicts the license 333 restrictions of other proprietary libraries that do not normally 334 accompany the operating system. Such a contradiction means you cannot 335 use both them and the Library together in an executable that you 336 distribute. 337 339 7. You may place library facilities that are a work based on the 340 Library side-by-side in a single library together with other library 341 facilities not covered by this License, and distribute such a combined 342 library, provided that the separate distribution of the work based on 343 the Library and of the other library facilities is otherwise 344 permitted, and provided that you do these two things: 345 346 a) Accompany the combined library with a copy of the same work 347 based on the Library, uncombined with any other library 348 facilities. This must be distributed under the terms of the 349 Sections above. 350 351 b) Give prominent notice with the combined library of the fact 352 that part of it is a work based on the Library, and explaining 353 where to find the accompanying uncombined form of the same work. 354 355 8. You may not copy, modify, sublicense, link with, or distribute 356 the Library except as expressly provided under this License. Any 357 attempt otherwise to copy, modify, sublicense, link with, or 358 distribute the Library is void, and will automatically terminate your 359 rights under this License. However, parties who have received copies, 360 or rights, from you under this License will not have their licenses 361 terminated so long as such parties remain in full compliance. 362 363 9. You are not required to accept this License, since you have not 364 signed it. However, nothing else grants you permission to modify or 365 distribute the Library or its derivative works. These actions are 366 prohibited by law if you do not accept this License. Therefore, by 367 modifying or distributing the Library (or any work based on the 368 Library), you indicate your acceptance of this License to do so, and 369 all its terms and conditions for copying, distributing or modifying 370 the Library or works based on it. 371 372 10. Each time you redistribute the Library (or any work based on the 373 Library), the recipient automatically receives a license from the 374 original licensor to copy, distribute, link with or modify the Library 375 subject to these terms and conditions. You may not impose any further 376 restrictions on the recipients' exercise of the rights granted herein. 377 You are not responsible for enforcing compliance by third parties with 378 this License. 379 381 11. If, as a consequence of a court judgment or allegation of patent 382 infringement or for any other reason (not limited to patent issues), 383 conditions are imposed on you (whether by court order, agreement or 384 otherwise) that contradict the conditions of this License, they do not 385 excuse you from the conditions of this License. If you cannot 386 distribute so as to satisfy simultaneously your obligations under this 387 License and any other pertinent obligations, then as a consequence you 388 may not distribute the Library at all. For example, if a patent 389 license would not permit royalty-free redistribution of the Library by 390 all those who receive copies directly or indirectly through you, then 391 the only way you could satisfy both it and this License would be to 392 refrain entirely from distribution of the Library. 393 394 If any portion of this section is held invalid or unenforceable under any 395 particular circumstance, the balance of the section is intended to apply, 396 and the section as a whole is intended to apply in other circumstances. 397 398 It is not the purpose of this section to induce you to infringe any 399 patents or other property right claims or to contest validity of any 400 such claims; this section has the sole purpose of protecting the 401 integrity of the free software distribution system which is 402 implemented by public license practices. Many people have made 403 generous contributions to the wide range of software distributed 404 through that system in reliance on consistent application of that 405 system; it is up to the author/donor to decide if he or she is willing 406 to distribute software through any other system and a licensee cannot 407 impose that choice. 408 409 This section is intended to make thoroughly clear what is believed to 410 be a consequence of the rest of this License. 411 412 12. If the distribution and/or use of the Library is restricted in 413 certain countries either by patents or by copyrighted interfaces, the 414 original copyright holder who places the Library under this License may add 415 an explicit geographical distribution limitation excluding those countries, 416 so that distribution is permitted only in or among countries not thus 417 excluded. In such case, this License incorporates the limitation as if 418 written in the body of this License. 419 420 13. The Free Software Foundation may publish revised and/or new 421 versions of the Lesser General Public License from time to time. 422 Such new versions will be similar in spirit to the present version, 423 but may differ in detail to address new problems or concerns. 424 425 Each version is given a distinguishing version number. If the Library 426 specifies a version number of this License which applies to it and 427 "any later version", you have the option of following the terms and 428 conditions either of that version or of any later version published by 429 the Free Software Foundation. If the Library does not specify a 430 license version number, you may choose any version ever published by 431 the Free Software Foundation. 432 434 14. If you wish to incorporate parts of the Library into other free 435 programs whose distribution conditions are incompatible with these, 436 write to the author to ask for permission. For software which is 437 copyrighted by the Free Software Foundation, write to the Free 438 Software Foundation; we sometimes make exceptions for this. Our 439 decision will be guided by the two goals of preserving the free status 440 of all derivatives of our free software and of promoting the sharing 441 and reuse of software generally. 442 443 NO WARRANTY 444 445 15. BECAUSE THE LIBRARY IS LICENSED FREE OF CHARGE, THERE IS NO 446 WARRANTY FOR THE LIBRARY, TO THE EXTENT PERMITTED BY APPLICABLE LAW. 447 EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR 448 OTHER PARTIES PROVIDE THE LIBRARY "AS IS" WITHOUT WARRANTY OF ANY 449 KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE 450 IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 451 PURPOSE. THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE 452 LIBRARY IS WITH YOU. SHOULD THE LIBRARY PROVE DEFECTIVE, YOU ASSUME 453 THE COST OF ALL NECESSARY SERVICING, REPAIR OR CORRECTION. 454 455 16. IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN 456 WRITING WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MAY MODIFY 457 AND/OR REDISTRIBUTE THE LIBRARY AS PERMITTED ABOVE, BE LIABLE TO YOU 458 FOR DAMAGES, INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL OR 459 CONSEQUENTIAL DAMAGES ARISING OUT OF THE USE OR INABILITY TO USE THE 460 LIBRARY (INCLUDING BUT NOT LIMITED TO LOSS OF DATA OR DATA BEING 461 RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD PARTIES OR A 462 FAILURE OF THE LIBRARY TO OPERATE WITH ANY OTHER SOFTWARE), EVEN IF 463 SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH 464 DAMAGES. 465 466 END OF TERMS AND CONDITIONS 467 469 How to Apply These Terms to Your New Libraries 470 471 If you develop a new library, and you want it to be of the greatest 472 possible use to the public, we recommend making it free software that 473 everyone can redistribute and change. You can do so by permitting 474 redistribution under these terms (or, alternatively, under the terms of the 475 ordinary General Public License). 476 477 To apply these terms, attach the following notices to the library. It is 478 safest to attach them to the start of each source file to most effectively 479 convey the exclusion of warranty; and each file should have at least the 480 "copyright" line and a pointer to where the full notice is found. 481 482 <one line to give the library's name and a brief idea of what it does.> 483 Copyright <year> <name of author> 484 485 This library is free software; you can redistribute it and/or 486 modify it under the terms of the GNU Lesser General Public 487 License as published by the Free Software Foundation; either 488 version 2.1 of the License, or (at your option) any later version. 489 490 This library is distributed in the hope that it will be useful, 491 but WITHOUT ANY WARRANTY; without even the implied warranty of 492 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 493 Lesser General Public License for more details. 494 495 You should have received a copy of the GNU Lesser General Public 496 License along with this library; if not, write to the Free Software 497 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 498 499 Also add information on how to contact you by electronic and paper mail. 500 501 You should also get your employer (if you work as a programmer) or your 502 school, if any, to sign a "copyright disclaimer" for the library, if 503 necessary. Here is a sample; alter the names: 504 505 Yoyodyne, Inc., hereby disclaims all copyright interest in the 506 library `Frob' (a library for tweaking knobs) written by James Random Hacker. 507 508 <signature of Ty Coon>, 1 April 1990 509 Ty Coon, President of Vice 510 511 That's all there is to it! 512 513 514