1 2 GNU LESSER GENERAL PUBLIC LICENSE 3 Version 2.1, February 1999 4 5 Copyright (C) 1991, 1999 Free Software Foundation, Inc. 6 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA 7 Everyone is permitted to copy and distribute verbatim copies 8 of this license document, but changing it is not allowed. 9 10 [This is the first released version of the Lesser GPL. It also counts 11 as the successor of the GNU Library Public License, version 2, hence 12 the version number 2.1.] 13 14 Preamble 15 16 The licenses for most software are designed to take away your 17 freedom to share and change it. By contrast, the GNU General Public 18 Licenses are intended to guarantee your freedom to share and change 19 free software--to make sure the software is free for all its users. 20 21 This license, the Lesser General Public License, applies to some 22 specially designated software packages--typically libraries--of the 23 Free Software Foundation and other authors who decide to use it. You 24 can use it too, but we suggest you first think carefully about whether 25 this license or the ordinary General Public License is the better 26 strategy to use in any particular case, based on the explanations 27 below. 28 29 When we speak of free software, we are referring to freedom of use, 30 not price. Our General Public Licenses are designed to make sure that 31 you have the freedom to distribute copies of free software (and charge 32 for this service if you wish); that you receive source code or can get 33 it if you want it; that you can change the software and use pieces of 34 it in new free programs; and that you are informed that you can do 35 these things. 36 37 To protect your rights, we need to make restrictions that forbid 38 distributors to deny you these rights or to ask you to surrender these 39 rights. These restrictions translate to certain responsibilities for 40 you if you distribute copies of the library or if you modify it. 41 42 For example, if you distribute copies of the library, whether gratis 43 or for a fee, you must give the recipients all the rights that we gave 44 you. You must make sure that they, too, receive or can get the source 45 code. If you link other code with the library, you must provide 46 complete object files to the recipients, so that they can relink them 47 with the library after making changes to the library and recompiling 48 it. And you must show them these terms so they know their rights. 49 50 We protect your rights with a two-step method: (1) we copyright the 51 library, and (2) we offer you this license, which gives you legal 52 permission to copy, distribute and/or modify the library. 53 54 To protect each distributor, we want to make it very clear that 55 there is no warranty for the free library. Also, if the library is 56 modified by someone else and passed on, the recipients should know 57 that what they have is not the original version, so that the original 58 author's reputation will not be affected by problems that might be 59 introduced by others. 60 ^L 61 Finally, software patents pose a constant threat to the existence of 62 any free program. We wish to make sure that a company cannot 63 effectively restrict the users of a free program by obtaining a 64 restrictive license from a patent holder. Therefore, we insist that 65 any patent license obtained for a version of the library must be 66 consistent with the full freedom of use specified in this license. 67 68 Most GNU software, including some libraries, is covered by the 69 ordinary GNU General Public License. This license, the GNU Lesser 70 General Public License, applies to certain designated libraries, and 71 is quite different from the ordinary General Public License. We use 72 this license for certain libraries in order to permit linking those 73 libraries into non-free programs. 74 75 When a program is linked with a library, whether statically or using 76 a shared library, the combination of the two is legally speaking a 77 combined work, a derivative of the original library. The ordinary 78 General Public License therefore permits such linking only if the 79 entire combination fits its criteria of freedom. The Lesser General 80 Public License permits more lax criteria for linking other code with 81 the library. 82 83 We call this license the "Lesser" General Public License because it 84 does Less to protect the user's freedom than the ordinary General 85 Public License. It also provides other free software developers Less 86 of an advantage over competing non-free programs. These disadvantages 87 are the reason we use the ordinary General Public License for many 88 libraries. However, the Lesser license provides advantages in certain 89 special circumstances. 90 91 For example, on rare occasions, there may be a special need to 92 encourage the widest possible use of a certain library, so that it 93 becomes 94 a de-facto standard. To achieve this, non-free programs must be 95 allowed to use the library. A more frequent case is that a free 96 library does the same job as widely used non-free libraries. In this 97 case, there is little to gain by limiting the free library to free 98 software only, so we use the Lesser General Public License. 99 100 In other cases, permission to use a particular library in non-free 101 programs enables a greater number of people to use a large body of 102 free software. For example, permission to use the GNU C Library in 103 non-free programs enables many more people to use the whole GNU 104 operating system, as well as its variant, the GNU/Linux operating 105 system. 106 107 Although the Lesser General Public License is Less protective of the 108 users' freedom, it does ensure that the user of a program that is 109 linked with the Library has the freedom and the wherewithal to run 110 that program using a modified version of the Library. 111 112 The precise terms and conditions for copying, distribution and 113 modification follow. Pay close attention to the difference between a 114 "work based on the library" and a "work that uses the library". The 115 former contains code derived from the library, whereas the latter must 116 be combined with the library in order to run. 117 ^L 118 GNU LESSER GENERAL PUBLIC LICENSE 119 TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION 120 121 0. This License Agreement applies to any software library or other 122 program which contains a notice placed by the copyright holder or 123 other authorized party saying it may be distributed under the terms of 124 this Lesser General Public License (also called "this License"). 125 Each licensee is addressed as "you". 126 127 A "library" means a collection of software functions and/or data 128 prepared so as to be conveniently linked with application programs 129 (which use some of those functions and data) to form executables. 130 131 The "Library", below, refers to any such software library or work 132 which has been distributed under these terms. A "work based on the 133 Library" means either the Library or any derivative work under 134 copyright law: that is to say, a work containing the Library or a 135 portion of it, either verbatim or with modifications and/or translated 136 straightforwardly into another language. (Hereinafter, translation is 137 included without limitation in the term "modification".) 138 139 "Source code" for a work means the preferred form of the work for 140 making modifications to it. For a library, complete source code means 141 all the source code for all modules it contains, plus any associated 142 interface definition files, plus the scripts used to control 143 compilation 144 and installation of the library. 145 146 Activities other than copying, distribution and modification are not 147 covered by this License; they are outside its scope. The act of 148 running a program using the Library is not restricted, and output from 149 such a program is covered only if its contents constitute a work based 150 on the Library (independent of the use of the Library in a tool for 151 writing it). Whether that is true depends on what the Library does 152 and what the program that uses the Library does. 153 154 1. You may copy and distribute verbatim copies of the Library's 155 complete source code as you receive it, in any medium, provided that 156 you conspicuously and appropriately publish on each copy an 157 appropriate copyright notice and disclaimer of warranty; keep intact 158 all the notices that refer to this License and to the absence of any 159 warranty; and distribute a copy of this License along with the 160 Library. 161 162 You may charge a fee for the physical act of transferring a copy, 163 and you may at your option offer warranty protection in exchange for a 164 fee. 165 167 2. You may modify your copy or copies of the Library or any portion 168 of it, thus forming a work based on the Library, and copy and 169 distribute such modifications or work under the terms of Section 1 170 above, provided that you also meet all of these conditions: 171 172 a) The modified work must itself be a software library. 173 174 b) You must cause the files modified to carry prominent notices 175 stating that you changed the files and the date of any change. 176 177 c) You must cause the whole of the work to be licensed at no 178 charge to all third parties under the terms of this License. 179 180 d) If a facility in the modified Library refers to a function or a 181 table of data to be supplied by an application program that uses 182 the facility, other than as an argument passed when the facility 183 is invoked, then you must make a good faith effort to ensure that, 184 in the event an application does not supply such function or 185 table, the facility still operates, and performs whatever part of 186 its purpose remains meaningful. 187 188 (For example, a function in a library to compute square roots has 189 a purpose that is entirely well-defined independent of the 190 application. Therefore, Subsection 2d requires that any 191 application-supplied function or table used by this function must 192 be optional: if the application does not supply it, the square 193 root function must still compute square roots.) 194 195 These requirements apply to the modified work as a whole. If 196 identifiable sections of that work are not derived from the Library, 197 and can be reasonably considered independent and separate works in 198 themselves, then this License, and its terms, do not apply to those 199 sections when you distribute them as separate works. But when you 200 distribute the same sections as part of a whole which is a work based 201 on the Library, the distribution of the whole must be on the terms of 202 this License, whose permissions for other licensees extend to the 203 entire whole, and thus to each and every part regardless of who wrote 204 it. 205 206 Thus, it is not the intent of this section to claim rights or contest 207 your rights to work written entirely by you; rather, the intent is to 208 exercise the right to control the distribution of derivative or 209 collective works based on the Library. 210 211 In addition, mere aggregation of another work not based on the Library 212 with the Library (or with a work based on the Library) on a volume of 213 a storage or distribution medium does not bring the other work under 214 the scope of this License. 215 216 3. You may opt to apply the terms of the ordinary GNU General Public 217 License instead of this License to a given copy of the Library. To do 218 this, you must alter all the notices that refer to this License, so 219 that they refer to the ordinary GNU General Public License, version 2, 220 instead of to this License. (If a newer version than version 2 of the 221 ordinary GNU General Public License has appeared, then you can specify 222 that version instead if you wish.) Do not make any other change in 223 these notices. 224 ^L 225 Once this change is made in a given copy, it is irreversible for 226 that copy, so the ordinary GNU General Public License applies to all 227 subsequent copies and derivative works made from that copy. 228 229 This option is useful when you wish to copy part of the code of 230 the Library into a program that is not a library. 231 232 4. You may copy and distribute the Library (or a portion or 233 derivative of it, under Section 2) in object code or executable form 234 under the terms of Sections 1 and 2 above provided that you accompany 235 it with the complete corresponding machine-readable source code, which 236 must be distributed under the terms of Sections 1 and 2 above on a 237 medium customarily used for software interchange. 238 239 If distribution of object code is made by offering access to copy 240 from a designated place, then offering equivalent access to copy the 241 source code from the same place satisfies the requirement to 242 distribute the source code, even though third parties are not 243 compelled to copy the source along with the object code. 244 245 5. A program that contains no derivative of any portion of the 246 Library, but is designed to work with the Library by being compiled or 247 linked with it, is called a "work that uses the Library". Such a 248 work, in isolation, is not a derivative work of the Library, and 249 therefore falls outside the scope of this License. 250 251 However, linking a "work that uses the Library" with the Library 252 creates an executable that is a derivative of the Library (because it 253 contains portions of the Library), rather than a "work that uses the 254 library". The executable is therefore covered by this License. 255 Section 6 states terms for distribution of such executables. 256 257 When a "work that uses the Library" uses material from a header file 258 that is part of the Library, the object code for the work may be a 259 derivative work of the Library even though the source code is not. 260 Whether this is true is especially significant if the work can be 261 linked without the Library, or if the work is itself a library. The 262 threshold for this to be true is not precisely defined by law. 263 264 If such an object file uses only numerical parameters, data 265 structure layouts and accessors, and small macros and small inline 266 functions (ten lines or less in length), then the use of the object 267 file is unrestricted, regardless of whether it is legally a derivative 268 work. (Executables containing this object code plus portions of the 269 Library will still fall under Section 6.) 270 271 Otherwise, if the work is a derivative of the Library, you may 272 distribute the object code for the work under the terms of Section 6. 273 Any executables containing that work also fall under Section 6, 274 whether or not they are linked directly with the Library itself. 275 ^L 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 ^L 338 7. You may place library facilities that are a work based on the 339 Library side-by-side in a single library together with other library 340 facilities not covered by this License, and distribute such a combined 341 library, provided that the separate distribution of the work based on 342 the Library and of the other library facilities is otherwise 343 permitted, and provided that you do these two things: 344 345 a) Accompany the combined library with a copy of the same work 346 based on the Library, uncombined with any other library 347 facilities. This must be distributed under the terms of the 348 Sections above. 349 350 b) Give prominent notice with the combined library of the fact 351 that part of it is a work based on the Library, and explaining 352 where to find the accompanying uncombined form of the same work. 353 354 8. You may not copy, modify, sublicense, link with, or distribute 355 the Library except as expressly provided under this License. Any 356 attempt otherwise to copy, modify, sublicense, link with, or 357 distribute the Library is void, and will automatically terminate your 358 rights under this License. However, parties who have received copies, 359 or rights, from you under this License will not have their licenses 360 terminated so long as such parties remain in full compliance. 361 362 9. You are not required to accept this License, since you have not 363 signed it. However, nothing else grants you permission to modify or 364 distribute the Library or its derivative works. These actions are 365 prohibited by law if you do not accept this License. Therefore, by 366 modifying or distributing the Library (or any work based on the 367 Library), you indicate your acceptance of this License to do so, and 368 all its terms and conditions for copying, distributing or modifying 369 the Library or works based on it. 370 371 10. Each time you redistribute the Library (or any work based on the 372 Library), the recipient automatically receives a license from the 373 original licensor to copy, distribute, link with or modify the Library 374 subject to these terms and conditions. You may not impose any further 375 restrictions on the recipients' exercise of the rights granted herein. 376 You are not responsible for enforcing compliance by third parties with 377 this License. 378 ^L 379 11. If, as a consequence of a court judgment or allegation of patent 380 infringement or for any other reason (not limited to patent issues), 381 conditions are imposed on you (whether by court order, agreement or 382 otherwise) that contradict the conditions of this License, they do not 383 excuse you from the conditions of this License. If you cannot 384 distribute so as to satisfy simultaneously your obligations under this 385 License and any other pertinent obligations, then as a consequence you 386 may not distribute the Library at all. For example, if a patent 387 license would not permit royalty-free redistribution of the Library by 388 all those who receive copies directly or indirectly through you, then 389 the only way you could satisfy both it and this License would be to 390 refrain entirely from distribution of the Library. 391 392 If any portion of this section is held invalid or unenforceable under 393 any particular circumstance, the balance of the section is intended to 394 apply, and the section as a whole is intended to apply in other 395 circumstances. 396 397 It is not the purpose of this section to induce you to infringe any 398 patents or other property right claims or to contest validity of any 399 such claims; this section has the sole purpose of protecting the 400 integrity of the free software distribution system which is 401 implemented by public license practices. Many people have made 402 generous contributions to the wide range of software distributed 403 through that system in reliance on consistent application of that 404 system; it is up to the author/donor to decide if he or she is willing 405 to distribute software through any other system and a licensee cannot 406 impose that choice. 407 408 This section is intended to make thoroughly clear what is believed to 409 be a consequence of the rest of this License. 410 411 12. If the distribution and/or use of the Library is restricted in 412 certain countries either by patents or by copyrighted interfaces, the 413 original copyright holder who places the Library under this License 414 may add an explicit geographical distribution limitation excluding those 415 countries, so that distribution is permitted only in or among 416 countries not thus excluded. In such case, this License incorporates 417 the limitation as if written in the body of this License. 418 419 13. The Free Software Foundation may publish revised and/or new 420 versions of the Lesser General Public License from time to time. 421 Such new versions will be similar in spirit to the present version, 422 but may differ in detail to address new problems or concerns. 423 424 Each version is given a distinguishing version number. If the Library 425 specifies a version number of this License which applies to it and 426 "any later version", you have the option of following the terms and 427 conditions either of that version or of any later version published by 428 the Free Software Foundation. If the Library does not specify a 429 license version number, you may choose any version ever published by 430 the Free Software Foundation. 431 ^L 432 14. If you wish to incorporate parts of the Library into other free 433 programs whose distribution conditions are incompatible with these, 434 write to the author to ask for permission. For software which is 435 copyrighted by the Free Software Foundation, write to the Free 436 Software Foundation; we sometimes make exceptions for this. Our 437 decision will be guided by the two goals of preserving the free status 438 of all derivatives of our free software and of promoting the sharing 439 and reuse of software generally. 440 441 NO WARRANTY 442 443 15. BECAUSE THE LIBRARY IS LICENSED FREE OF CHARGE, THERE IS NO 444 WARRANTY FOR THE LIBRARY, TO THE EXTENT PERMITTED BY APPLICABLE LAW. 445 EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR 446 OTHER PARTIES PROVIDE THE LIBRARY "AS IS" WITHOUT WARRANTY OF ANY 447 KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE 448 IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 449 PURPOSE. THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE 450 LIBRARY IS WITH YOU. SHOULD THE LIBRARY PROVE DEFECTIVE, YOU ASSUME 451 THE COST OF ALL NECESSARY SERVICING, REPAIR OR CORRECTION. 452 453 16. IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN 454 WRITING WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MAY MODIFY 455 AND/OR REDISTRIBUTE THE LIBRARY AS PERMITTED ABOVE, BE LIABLE TO YOU 456 FOR DAMAGES, INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL OR 457 CONSEQUENTIAL DAMAGES ARISING OUT OF THE USE OR INABILITY TO USE THE 458 LIBRARY (INCLUDING BUT NOT LIMITED TO LOSS OF DATA OR DATA BEING 459 RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD PARTIES OR A 460 FAILURE OF THE LIBRARY TO OPERATE WITH ANY OTHER SOFTWARE), EVEN IF 461 SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH 462 DAMAGES. 463 464 END OF TERMS AND CONDITIONS 465 ^L 466 How to Apply These Terms to Your New Libraries 467 468 If you develop a new library, and you want it to be of the greatest 469 possible use to the public, we recommend making it free software that 470 everyone can redistribute and change. You can do so by permitting 471 redistribution under these terms (or, alternatively, under the terms 472 of the ordinary General Public License). 473 474 To apply these terms, attach the following notices to the library. 475 It is safest to attach them to the start of each source file to most 476 effectively convey the exclusion of warranty; and each file should 477 have at least the "copyright" line and a pointer to where the full 478 notice is found. 479 480 481 <one line to give the library's name and a brief idea of what it 482 does.> 483 Copyright (C) <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 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA 498 499 Also add information on how to contact you by electronic and paper 500 mail. 501 502 You should also get your employer (if you work as a programmer) or 503 your 504 school, if any, to sign a "copyright disclaimer" for the library, if 505 necessary. Here is a sample; alter the names: 506 507 Yoyodyne, Inc., hereby disclaims all copyright interest in the 508 library `Frob' (a library for tweaking knobs) written by James 509 Random Hacker. 510 511 <signature of Ty Coon>, 1 April 1990 512 Ty Coon, President of Vice 513 514 That's all there is to it! 515 516 517
