gpl.texinfo revision 256281
1@c This GPL is meant to be included from other files. 2@c To format a standalone GPL, use license.texi. 3 4@center Version 2, June 1991 5 6@display 7Copyright @copyright{} 1989, 1991 Free Software Foundation, Inc., 859 Temple Place, Suite 330, Boston, MA 02111-1307, USA. 9 10Everyone is permitted to copy and distribute verbatim copies 11of this license document, but changing it is not allowed. 12@end display 13 14@unnumberedsec Preamble 15 16 The licenses for most software are designed to take away your 17freedom to share and change it. By contrast, the GNU General Public 18License is intended to guarantee your freedom to share and change free 19software---to make sure the software is free for all its users. This 20General Public License applies to most of the Free Software 21Foundation's software and to any other program whose authors commit to 22using it. (Some other Free Software Foundation software is covered by 23the GNU Library General Public License instead.) You can apply it to 24your programs, too. 25 26 When we speak of free software, we are referring to freedom, not 27price. Our General Public Licenses are designed to make sure that you 28have the freedom to distribute copies of free software (and charge for 29this service if you wish), that you receive source code or can get it 30if you want it, that you can change the software or use pieces of it 31in new free programs; and that you know you can do these things. 32 33 To protect your rights, we need to make restrictions that forbid 34anyone to deny you these rights or to ask you to surrender the rights. 35These restrictions translate to certain responsibilities for you if you 36distribute copies of the software, or if you modify it. 37 38 For example, if you distribute copies of such a program, whether 39gratis or for a fee, you must give the recipients all the rights that 40you have. You must make sure that they, too, receive or can get the 41source code. And you must show them these terms so they know their 42rights. 43 44 We protect your rights with two steps: (1) copyright the software, and 45(2) offer you this license which gives you legal permission to copy, 46distribute and/or modify the software. 47 48 Also, for each author's protection and ours, we want to make certain 49that everyone understands that there is no warranty for this free 50software. If the software is modified by someone else and passed on, we 51want its recipients to know that what they have is not the original, so 52that any problems introduced by others will not reflect on the original 53authors' reputations. 54 55 Finally, any free program is threatened constantly by software 56patents. We wish to avoid the danger that redistributors of a free 57program will individually obtain patent licenses, in effect making the 58program proprietary. To prevent this, we have made it clear that any 59patent must be licensed for everyone's free use or not licensed at all. 60 61 The precise terms and conditions for copying, distribution and 62modification follow. 63 64@iftex 65@unnumberedsec TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION 66@end iftex 67@ifinfo 68@center TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION 69@end ifinfo 70 71@enumerate 0 72@item 73This License applies to any program or other work which contains 74a notice placed by the copyright holder saying it may be distributed 75under the terms of this General Public License. The ``Program'', below, 76refers to any such program or work, and a ``work based on the Program'' 77means either the Program or any derivative work under copyright law: 78that is to say, a work containing the Program or a portion of it, 79either verbatim or with modifications and/or translated into another 80language. (Hereinafter, translation is included without limitation in 81the term ``modification''.) Each licensee is addressed as ``you''. 82 83Activities other than copying, distribution and modification are not 84covered by this License; they are outside its scope. The act of 85running the Program is not restricted, and the output from the Program 86is covered only if its contents constitute a work based on the 87Program (independent of having been made by running the Program). 88Whether that is true depends on what the Program does. 89 90@item 91You may copy and distribute verbatim copies of the Program's 92source code as you receive it, in any medium, provided that you 93conspicuously and appropriately publish on each copy an appropriate 94copyright notice and disclaimer of warranty; keep intact all the 95notices that refer to this License and to the absence of any warranty; 96and give any other recipients of the Program a copy of this License 97along with the Program. 98 99You may charge a fee for the physical act of transferring a copy, and 100you may at your option offer warranty protection in exchange for a fee. 101 102@item 103You may modify your copy or copies of the Program or any portion 104of it, thus forming a work based on the Program, and copy and 105distribute such modifications or work under the terms of Section 1 106above, provided that you also meet all of these conditions: 107 108@enumerate a 109@item 110You must cause the modified files to carry prominent notices 111stating that you changed the files and the date of any change. 112 113@item 114You must cause any work that you distribute or publish, that in 115whole or in part contains or is derived from the Program or any 116part thereof, to be licensed as a whole at no charge to all third 117parties under the terms of this License. 118 119@item 120If the modified program normally reads commands interactively 121when run, you must cause it, when started running for such 122interactive use in the most ordinary way, to print or display an 123announcement including an appropriate copyright notice and a 124notice that there is no warranty (or else, saying that you provide 125a warranty) and that users may redistribute the program under 126these conditions, and telling the user how to view a copy of this 127License. (Exception: if the Program itself is interactive but 128does not normally print such an announcement, your work based on 129the Program is not required to print an announcement.) 130@end enumerate 131 132These requirements apply to the modified work as a whole. If 133identifiable sections of that work are not derived from the Program, 134and can be reasonably considered independent and separate works in 135themselves, then this License, and its terms, do not apply to those 136sections when you distribute them as separate works. But when you 137distribute the same sections as part of a whole which is a work based 138on the Program, the distribution of the whole must be on the terms of 139this License, whose permissions for other licensees extend to the 140entire whole, and thus to each and every part regardless of who wrote it. 141 142Thus, it is not the intent of this section to claim rights or contest 143your rights to work written entirely by you; rather, the intent is to 144exercise the right to control the distribution of derivative or 145collective works based on the Program. 146 147In addition, mere aggregation of another work not based on the Program 148with the Program (or with a work based on the Program) on a volume of 149a storage or distribution medium does not bring the other work under 150the scope of this License. 151 152@item 153You may copy and distribute the Program (or a work based on it, 154under Section 2) in object code or executable form under the terms of 155Sections 1 and 2 above provided that you also do one of the following: 156 157@enumerate a 158@item 159Accompany it with the complete corresponding machine-readable 160source code, which must be distributed under the terms of Sections 1611 and 2 above on a medium customarily used for software interchange; or, 162 163@item 164Accompany it with a written offer, valid for at least three 165years, to give any third party, for a charge no more than your 166cost of physically performing source distribution, a complete 167machine-readable copy of the corresponding source code, to be 168distributed under the terms of Sections 1 and 2 above on a medium 169customarily used for software interchange; or, 170 171@item 172Accompany it with the information you received as to the offer 173to distribute corresponding source code. (This alternative is 174allowed only for noncommercial distribution and only if you 175received the program in object code or executable form with such 176an offer, in accord with Subsection b above.) 177@end enumerate 178 179The source code for a work means the preferred form of the work for 180making modifications to it. For an executable work, complete source 181code means all the source code for all modules it contains, plus any 182associated interface definition files, plus the scripts used to 183control compilation and installation of the executable. However, as a 184special exception, the source code distributed need not include 185anything that is normally distributed (in either source or binary 186form) with the major components (compiler, kernel, and so on) of the 187operating system on which the executable runs, unless that component 188itself accompanies the executable. 189 190If distribution of executable or object code is made by offering 191access to copy from a designated place, then offering equivalent 192access to copy the source code from the same place counts as 193distribution of the source code, even though third parties are not 194compelled to copy the source along with the object code. 195 196@item 197You may not copy, modify, sublicense, or distribute the Program 198except as expressly provided under this License. Any attempt 199otherwise to copy, modify, sublicense or distribute the Program is 200void, and will automatically terminate your rights under this License. 201However, parties who have received copies, or rights, from you under 202this License will not have their licenses terminated so long as such 203parties remain in full compliance. 204 205@item 206You are not required to accept this License, since you have not 207signed it. However, nothing else grants you permission to modify or 208distribute the Program or its derivative works. These actions are 209prohibited by law if you do not accept this License. Therefore, by 210modifying or distributing the Program (or any work based on the 211Program), you indicate your acceptance of this License to do so, and 212all its terms and conditions for copying, distributing or modifying 213the Program or works based on it. 214 215@item 216Each time you redistribute the Program (or any work based on the 217Program), the recipient automatically receives a license from the 218original licensor to copy, distribute or modify the Program subject to 219these terms and conditions. You may not impose any further 220restrictions on the recipients' exercise of the rights granted herein. 221You are not responsible for enforcing compliance by third parties to 222this License. 223 224@item 225If, as a consequence of a court judgment or allegation of patent 226infringement or for any other reason (not limited to patent issues), 227conditions are imposed on you (whether by court order, agreement or 228otherwise) that contradict the conditions of this License, they do not 229excuse you from the conditions of this License. If you cannot 230distribute so as to satisfy simultaneously your obligations under this 231License and any other pertinent obligations, then as a consequence you 232may not distribute the Program at all. For example, if a patent 233license would not permit royalty-free redistribution of the Program by 234all those who receive copies directly or indirectly through you, then 235the only way you could satisfy both it and this License would be to 236refrain entirely from distribution of the Program. 237 238If any portion of this section is held invalid or unenforceable under 239any particular circumstance, the balance of the section is intended to 240apply and the section as a whole is intended to apply in other 241circumstances. 242 243It is not the purpose of this section to induce you to infringe any 244patents or other property right claims or to contest validity of any 245such claims; this section has the sole purpose of protecting the 246integrity of the free software distribution system, which is 247implemented by public license practices. Many people have made 248generous contributions to the wide range of software distributed 249through that system in reliance on consistent application of that 250system; it is up to the author/donor to decide if he or she is willing 251to distribute software through any other system and a licensee cannot 252impose that choice. 253 254This section is intended to make thoroughly clear what is believed to 255be a consequence of the rest of this License. 256 257@item 258If the distribution and/or use of the Program is restricted in 259certain countries either by patents or by copyrighted interfaces, the 260original copyright holder who places the Program under this License 261may add an explicit geographical distribution limitation excluding 262those countries, so that distribution is permitted only in or among 263countries not thus excluded. In such case, this License incorporates 264the limitation as if written in the body of this License. 265 266@item 267The Free Software Foundation may publish revised and/or new versions 268of the General Public License from time to time. Such new versions will 269be similar in spirit to the present version, but may differ in detail to 270address new problems or concerns. 271 272Each version is given a distinguishing version number. If the Program 273specifies a version number of this License which applies to it and ``any 274later version'', you have the option of following the terms and conditions 275either of that version or of any later version published by the Free 276Software Foundation. If the Program does not specify a version number of 277this License, you may choose any version ever published by the Free Software 278Foundation. 279 280@item 281If you wish to incorporate parts of the Program into other free 282programs whose distribution conditions are different, write to the author 283to ask for permission. For software which is copyrighted by the Free 284Software Foundation, write to the Free Software Foundation; we sometimes 285make exceptions for this. Our decision will be guided by the two goals 286of preserving the free status of all derivatives of our free software and 287of promoting the sharing and reuse of software generally. 288 289@iftex 290@vskip -@baselineskip 291@vskip -@baselineskip 292@heading NO WARRANTY 293@end iftex 294@ifinfo 295@center NO WARRANTY 296@end ifinfo 297 298@item 299BECAUSE THE PROGRAM IS LICENSED FREE OF CHARGE, THERE IS NO WARRANTY 300FOR THE PROGRAM, TO THE EXTENT PERMITTED BY APPLICABLE LAW. EXCEPT WHEN 301OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES 302PROVIDE THE PROGRAM ``AS IS'' WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED 303OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 304MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE ENTIRE RISK AS 305TO THE QUALITY AND PERFORMANCE OF THE PROGRAM IS WITH YOU. SHOULD THE 306PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF ALL NECESSARY SERVICING, 307REPAIR OR CORRECTION. 308 309@item 310IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING 311WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MAY MODIFY AND/OR 312REDISTRIBUTE THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, 313INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING 314OUT OF THE USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED 315TO LOSS OF DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY 316YOU OR THIRD PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER 317PROGRAMS), EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE 318POSSIBILITY OF SUCH DAMAGES. 319@end enumerate 320 321@iftex 322@heading END OF TERMS AND CONDITIONS 323@end iftex 324@ifinfo 325@center END OF TERMS AND CONDITIONS 326@end ifinfo 327 328@page 329@unnumberedsec How to Apply These Terms to Your New Programs 330 331 If you develop a new program, and you want it to be of the greatest 332possible use to the public, the best way to achieve this is to make it 333free software which everyone can redistribute and change under these terms. 334 335 To do so, attach the following notices to the program. It is safest 336to attach them to the start of each source file to most effectively 337convey the exclusion of warranty; and each file should have at least 338the ``copyright'' line and a pointer to where the full notice is found. 339 340@smallexample 341@var{one line to give the program's name and an idea of what it does.} 342Copyright (C) @var{year} @var{name of author} 343 344This program is free software; you can redistribute it and/or 345modify it under the terms of the GNU General Public License 346as published by the Free Software Foundation; either version 2 347of the License, or (at your option) any later version. 348 349This program is distributed in the hope that it will be useful, 350but WITHOUT ANY WARRANTY; without even the implied warranty of 351MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 352GNU General Public License for more details. 353 354You should have received a copy of the GNU General Public License 355along with this program; if not, write to the Free Software 356Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307, USA. 357@end smallexample 358 359Also add information on how to contact you by electronic and paper mail. 360 361If the program is interactive, make it output a short notice like this 362when it starts in an interactive mode: 363 364@smallexample 365Gnomovision version 69, Copyright (C) @var{year} @var{name of author} 366Gnomovision comes with ABSOLUTELY NO WARRANTY; for details 367type `show w'. This is free software, and you are welcome 368to redistribute it under certain conditions; type `show c' 369for details. 370@end smallexample 371 372The hypothetical commands @samp{show w} and @samp{show c} should show 373the appropriate parts of the General Public License. Of course, the 374commands you use may be called something other than @samp{show w} and 375@samp{show c}; they could even be mouse-clicks or menu items---whatever 376suits your program. 377 378You should also get your employer (if you work as a programmer) or your 379school, if any, to sign a ``copyright disclaimer'' for the program, if 380necessary. Here is a sample; alter the names: 381 382@example 383@group 384Yoyodyne, Inc., hereby disclaims all copyright 385interest in the program `Gnomovision' 386(which makes passes at compilers) written 387by James Hacker. 388 389@var{signature of Ty Coon}, 1 April 1989 390Ty Coon, President of Vice 391@end group 392@end example 393 394This General Public License does not permit incorporating your program into 395proprietary programs. If your program is a subroutine library, you may 396consider it more useful to permit linking proprietary applications with the 397library. If this is what you want to do, use the GNU Library General 398Public License instead of this License. 399