1@node Copying 2@unnumbered GNU GENERAL PUBLIC LICENSE 3@center Version 2, June 1991 4 5@c This file is intended to be included in another file. 6 7@display 8Copyright @copyright{} 1989, 1991 Free Software Foundation, Inc. 951 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA 10 11Everyone is permitted to copy and distribute verbatim copies 12of this license document, but changing it is not allowed. 13@end display 14 15@unnumberedsec Preamble 16 17 The licenses for most software are designed to take away your 18freedom to share and change it. By contrast, the GNU General Public 19License is intended to guarantee your freedom to share and change free 20software---to make sure the software is free for all its users. This 21General Public License applies to most of the Free Software 22Foundation's software and to any other program whose authors commit to 23using it. (Some other Free Software Foundation software is covered by 24the GNU Library General Public License instead.) You can apply it to 25your programs, too. 26 27 When we speak of free software, we are referring to freedom, not 28price. Our General Public Licenses are designed to make sure that you 29have the freedom to distribute copies of free software (and charge for 30this service if you wish), that you receive source code or can get it 31if you want it, that you can change the software or use pieces of it 32in new free programs; and that you know you can do these things. 33 34 To protect your rights, we need to make restrictions that forbid 35anyone to deny you these rights or to ask you to surrender the rights. 36These restrictions translate to certain responsibilities for you if you 37distribute copies of the software, or if you modify it. 38 39 For example, if you distribute copies of such a program, whether 40gratis or for a fee, you must give the recipients all the rights that 41you have. You must make sure that they, too, receive or can get the 42source code. And you must show them these terms so they know their 43rights. 44 45 We protect your rights with two steps: (1) copyright the software, and 46(2) offer you this license which gives you legal permission to copy, 47distribute and/or modify the software. 48 49 Also, for each author's protection and ours, we want to make certain 50that everyone understands that there is no warranty for this free 51software. If the software is modified by someone else and passed on, we 52want its recipients to know that what they have is not the original, so 53that any problems introduced by others will not reflect on the original 54authors' reputations. 55 56 Finally, any free program is threatened constantly by software 57patents. We wish to avoid the danger that redistributors of a free 58program will individually obtain patent licenses, in effect making the 59program proprietary. To prevent this, we have made it clear that any 60patent must be licensed for everyone's free use or not licensed at all. 61 62 The precise terms and conditions for copying, distribution and 63modification follow. 64 65@iftex 66@unnumberedsec TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION 67@end iftex 68@ifinfo 69@center TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION 70@end ifinfo 71 72@enumerate 0 73@item 74This License applies to any program or other work which contains 75a notice placed by the copyright holder saying it may be distributed 76under the terms of this General Public License. The ``Program'', below, 77refers to any such program or work, and a ``work based on the Program'' 78means either the Program or any derivative work under copyright law: 79that is to say, a work containing the Program or a portion of it, 80either verbatim or with modifications and/or translated into another 81language. (Hereinafter, translation is included without limitation in 82the term ``modification''.) Each licensee is addressed as ``you''. 83 84Activities other than copying, distribution and modification are not 85covered by this License; they are outside its scope. The act of 86running the Program is not restricted, and the output from the Program 87is covered only if its contents constitute a work based on the 88Program (independent of having been made by running the Program). 89Whether that is true depends on what the Program does. 90 91@item 92You may copy and distribute verbatim copies of the Program's 93source code as you receive it, in any medium, provided that you 94conspicuously and appropriately publish on each copy an appropriate 95copyright notice and disclaimer of warranty; keep intact all the 96notices that refer to this License and to the absence of any warranty; 97and give any other recipients of the Program a copy of this License 98along with the Program. 99 100You may charge a fee for the physical act of transferring a copy, and 101you may at your option offer warranty protection in exchange for a fee. 102 103@item 104You may modify your copy or copies of the Program or any portion 105of it, thus forming a work based on the Program, and copy and 106distribute such modifications or work under the terms of Section 1 107above, provided that you also meet all of these conditions: 108 109@enumerate a 110@item 111You must cause the modified files to carry prominent notices 112stating that you changed the files and the date of any change. 113 114@item 115You must cause any work that you distribute or publish, that in 116whole or in part contains or is derived from the Program or any 117part thereof, to be licensed as a whole at no charge to all third 118parties under the terms of this License. 119 120@item 121If the modified program normally reads commands interactively 122when run, you must cause it, when started running for such 123interactive use in the most ordinary way, to print or display an 124announcement including an appropriate copyright notice and a 125notice that there is no warranty (or else, saying that you provide 126a warranty) and that users may redistribute the program under 127these conditions, and telling the user how to view a copy of this 128License. (Exception: if the Program itself is interactive but 129does not normally print such an announcement, your work based on 130the Program is not required to print an announcement.) 131@end enumerate 132 133These requirements apply to the modified work as a whole. If 134identifiable sections of that work are not derived from the Program, 135and can be reasonably considered independent and separate works in 136themselves, then this License, and its terms, do not apply to those 137sections when you distribute them as separate works. But when you 138distribute the same sections as part of a whole which is a work based 139on the Program, the distribution of the whole must be on the terms of 140this License, whose permissions for other licensees extend to the 141entire whole, and thus to each and every part regardless of who wrote it. 142 143Thus, it is not the intent of this section to claim rights or contest 144your rights to work written entirely by you; rather, the intent is to 145exercise the right to control the distribution of derivative or 146collective works based on the Program. 147 148In addition, mere aggregation of another work not based on the Program 149with the Program (or with a work based on the Program) on a volume of 150a storage or distribution medium does not bring the other work under 151the scope of this License. 152 153@item 154You may copy and distribute the Program (or a work based on it, 155under Section 2) in object code or executable form under the terms of 156Sections 1 and 2 above provided that you also do one of the following: 157 158@enumerate a 159@item 160Accompany it with the complete corresponding machine-readable 161source code, which must be distributed under the terms of Sections 1621 and 2 above on a medium customarily used for software interchange; or, 163 164@item 165Accompany it with a written offer, valid for at least three 166years, to give any third party, for a charge no more than your 167cost of physically performing source distribution, a complete 168machine-readable copy of the corresponding source code, to be 169distributed under the terms of Sections 1 and 2 above on a medium 170customarily used for software interchange; or, 171 172@item 173Accompany it with the information you received as to the offer 174to distribute corresponding source code. (This alternative is 175allowed only for noncommercial distribution and only if you 176received the program in object code or executable form with such 177an offer, in accord with Subsection b above.) 178@end enumerate 179 180The source code for a work means the preferred form of the work for 181making modifications to it. For an executable work, complete source 182code means all the source code for all modules it contains, plus any 183associated interface definition files, plus the scripts used to 184control compilation and installation of the executable. However, as a 185special exception, the source code distributed need not include 186anything that is normally distributed (in either source or binary 187form) with the major components (compiler, kernel, and so on) of the 188operating system on which the executable runs, unless that component 189itself accompanies the executable. 190 191If distribution of executable or object code is made by offering 192access to copy from a designated place, then offering equivalent 193access to copy the source code from the same place counts as 194distribution of the source code, even though third parties are not 195compelled to copy the source along with the object code. 196 197@item 198You may not copy, modify, sublicense, or distribute the Program 199except as expressly provided under this License. Any attempt 200otherwise to copy, modify, sublicense or distribute the Program is 201void, and will automatically terminate your rights under this License. 202However, parties who have received copies, or rights, from you under 203this License will not have their licenses terminated so long as such 204parties remain in full compliance. 205 206@item 207You are not required to accept this License, since you have not 208signed it. However, nothing else grants you permission to modify or 209distribute the Program or its derivative works. These actions are 210prohibited by law if you do not accept this License. Therefore, by 211modifying or distributing the Program (or any work based on the 212Program), you indicate your acceptance of this License to do so, and 213all its terms and conditions for copying, distributing or modifying 214the Program or works based on it. 215 216@item 217Each time you redistribute the Program (or any work based on the 218Program), the recipient automatically receives a license from the 219original licensor to copy, distribute or modify the Program subject to 220these terms and conditions. You may not impose any further 221restrictions on the recipients' exercise of the rights granted herein. 222You are not responsible for enforcing compliance by third parties to 223this License. 224 225@item 226If, as a consequence of a court judgment or allegation of patent 227infringement or for any other reason (not limited to patent issues), 228conditions are imposed on you (whether by court order, agreement or 229otherwise) that contradict the conditions of this License, they do not 230excuse you from the conditions of this License. If you cannot 231distribute so as to satisfy simultaneously your obligations under this 232License and any other pertinent obligations, then as a consequence you 233may not distribute the Program at all. For example, if a patent 234license would not permit royalty-free redistribution of the Program by 235all those who receive copies directly or indirectly through you, then 236the only way you could satisfy both it and this License would be to 237refrain entirely from distribution of the Program. 238 239If any portion of this section is held invalid or unenforceable under 240any particular circumstance, the balance of the section is intended to 241apply and the section as a whole is intended to apply in other 242circumstances. 243 244It is not the purpose of this section to induce you to infringe any 245patents or other property right claims or to contest validity of any 246such claims; this section has the sole purpose of protecting the 247integrity of the free software distribution system, which is 248implemented by public license practices. Many people have made 249generous contributions to the wide range of software distributed 250through that system in reliance on consistent application of that 251system; it is up to the author/donor to decide if he or she is willing 252to distribute software through any other system and a licensee cannot 253impose that choice. 254 255This section is intended to make thoroughly clear what is believed to 256be a consequence of the rest of this License. 257 258@item 259If the distribution and/or use of the Program is restricted in 260certain countries either by patents or by copyrighted interfaces, the 261original copyright holder who places the Program under this License 262may add an explicit geographical distribution limitation excluding 263those countries, so that distribution is permitted only in or among 264countries not thus excluded. In such case, this License incorporates 265the limitation as if written in the body of this License. 266 267@item 268The Free Software Foundation may publish revised and/or new versions 269of the General Public License from time to time. Such new versions will 270be similar in spirit to the present version, but may differ in detail to 271address new problems or concerns. 272 273Each version is given a distinguishing version number. If the Program 274specifies a version number of this License which applies to it and ``any 275later version'', you have the option of following the terms and conditions 276either of that version or of any later version published by the Free 277Software Foundation. If the Program does not specify a version number of 278this License, you may choose any version ever published by the Free Software 279Foundation. 280 281@item 282If you wish to incorporate parts of the Program into other free 283programs whose distribution conditions are different, write to the author 284to ask for permission. For software which is copyrighted by the Free 285Software Foundation, write to the Free Software Foundation; we sometimes 286make exceptions for this. Our decision will be guided by the two goals 287of preserving the free status of all derivatives of our free software and 288of promoting the sharing and reuse of software generally. 289 290@iftex 291@heading NO WARRANTY 292@end iftex 293@ifinfo 294@center NO WARRANTY 295@end ifinfo 296 297@item 298BECAUSE THE PROGRAM IS LICENSED FREE OF CHARGE, THERE IS NO WARRANTY 299FOR THE PROGRAM, TO THE EXTENT PERMITTED BY APPLICABLE LAW. EXCEPT WHEN 300OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES 301PROVIDE THE PROGRAM ``AS IS'' WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED 302OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 303MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE ENTIRE RISK AS 304TO THE QUALITY AND PERFORMANCE OF THE PROGRAM IS WITH YOU. SHOULD THE 305PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF ALL NECESSARY SERVICING, 306REPAIR OR CORRECTION. 307 308@item 309IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING 310WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MAY MODIFY AND/OR 311REDISTRIBUTE THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, 312INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING 313OUT OF THE USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED 314TO LOSS OF DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY 315YOU OR THIRD PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER 316PROGRAMS), EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE 317POSSIBILITY OF SUCH DAMAGES. 318@end enumerate 319 320@iftex 321@heading END OF TERMS AND CONDITIONS 322@end iftex 323@ifinfo 324@center END OF TERMS AND CONDITIONS 325@end ifinfo 326 327@page 328@unnumberedsec Appendix: How to Apply These Terms to Your New Programs 329 330 If you develop a new program, and you want it to be of the greatest 331possible use to the public, the best way to achieve this is to make it 332free software which everyone can redistribute and change under these terms. 333 334 To do so, attach the following notices to the program. It is safest 335to attach them to the start of each source file to most effectively 336convey the exclusion of warranty; and each file should have at least 337the ``copyright'' line and a pointer to where the full notice is found. 338 339@smallexample 340@var{one line to give the program's name and a brief idea of what it does.} 341Copyright (C) @var{yyyy} @var{name of author} 342 343This program is free software; you can redistribute it and/or modify 344it under the terms of the GNU General Public License as published by 345the Free Software Foundation; either version 2 of the License, or 346(at your option) any later version. 347 348This program is distributed in the hope that it will be useful, 349but WITHOUT ANY WARRANTY; without even the implied warranty of 350MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 351GNU General Public License for more details. 352 353You should have received a copy of the GNU General Public License 354along with this program; if not, write to the Free Software 355Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. 356@end smallexample 357 358Also add information on how to contact you by electronic and paper mail. 359 360If the program is interactive, make it output a short notice like this 361when it starts in an interactive mode: 362 363@smallexample 364Gnomovision version 69, Copyright (C) 19@var{yy} @var{name of author} 365Gnomovision comes with ABSOLUTELY NO WARRANTY; for details type `show w'. 366This is free software, and you are welcome to redistribute it 367under certain conditions; type `show c' for details. 368@end smallexample 369 370The hypothetical commands @samp{show w} and @samp{show c} should show 371the appropriate parts of the General Public License. Of course, the 372commands you use may be called something other than @samp{show w} and 373@samp{show c}; they could even be mouse-clicks or menu items---whatever 374suits your program. 375 376You should also get your employer (if you work as a programmer) or your 377school, if any, to sign a ``copyright disclaimer'' for the program, if 378necessary. Here is a sample; alter the names: 379 380@example 381Yoyodyne, Inc., hereby disclaims all copyright interest in the program 382`Gnomovision' (which makes passes at compilers) written by James Hacker. 383 384@var{signature of Ty Coon}, 1 April 1989 385Ty Coon, President of Vice 386@end example 387 388This General Public License does not permit incorporating your program into 389proprietary programs. If your program is a subroutine library, you may 390consider it more useful to permit linking proprietary applications with the 391library. If this is what you want to do, use the GNU Library General 392Public License instead of this License. 393