1 2 NOTE! This copyright does *not* cover user programs that use kernel 3 services by normal system calls - this is merely considered normal use 4 of the kernel, and does *not* fall under the heading of "derived work". 5 Also note that the GPL below is copyrighted by the Free Software 6 Foundation, but the instance of code that it refers to (the linux 7 kernel) is copyrighted by me and others who actually wrote it. 8 9 Linus Torvalds 10 11 ---------------------------------------- 12 13 GNU GENERAL PUBLIC LICENSE 14 Version 2, June 1991 15 16 Copyright (C) 1989, 1991 Free Software Foundation, Inc. 17 675 Mass Ave, Cambridge, MA 02139, USA 18 Everyone is permitted to copy and distribute verbatim copies 19 of this license document, but changing it is not allowed. 20 21 Preamble 22 23 The licenses for most software are designed to take away your 24 freedom to share and change it. By contrast, the GNU General Public 25 License is intended to guarantee your freedom to share and change free 26 software--to make sure the software is free for all its users. This 27 General Public License applies to most of the Free Software 28 Foundation's software and to any other program whose authors commit to 29 using it. (Some other Free Software Foundation software is covered by 30 the GNU Library General Public License instead.) You can apply it to 31 your programs, too. 32 33 When we speak of free software, we are referring to freedom, not 34 price. Our General Public Licenses are designed to make sure that you 35 have the freedom to distribute copies of free software (and charge for 36 this service if you wish), that you receive source code or can get it 37 if you want it, that you can change the software or use pieces of it 38 in new free programs; and that you know you can do these things. 39 40 To protect your rights, we need to make restrictions that forbid 41 anyone to deny you these rights or to ask you to surrender the rights. 42 These restrictions translate to certain responsibilities for you if you 43 distribute copies of the software, or if you modify it. 44 45 For example, if you distribute copies of such a program, whether 46 gratis or for a fee, you must give the recipients all the rights that 47 you have. You must make sure that they, too, receive or can get the 48 source code. And you must show them these terms so they know their 49 rights. 50 51 We protect your rights with two steps: (1) copyright the software, and 52 (2) offer you this license which gives you legal permission to copy, 53 distribute and/or modify the software. 54 55 Also, for each author's protection and ours, we want to make certain 56 that everyone understands that there is no warranty for this free 57 software. If the software is modified by someone else and passed on, we 58 want its recipients to know that what they have is not the original, so 59 that any problems introduced by others will not reflect on the original 60 authors' reputations. 61 62 Finally, any free program is threatened constantly by software 63 patents. We wish to avoid the danger that redistributors of a free 64 program will individually obtain patent licenses, in effect making the 65 program proprietary. To prevent this, we have made it clear that any 66 patent must be licensed for everyone's free use or not licensed at all. 67 68 The precise terms and conditions for copying, distribution and 69 modification follow. 70 72 GNU GENERAL PUBLIC LICENSE 73 TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION 74 75 0. This License applies to any program or other work which contains 76 a notice placed by the copyright holder saying it may be distributed 77 under the terms of this General Public License. The "Program", below, 78 refers to any such program or work, and a "work based on the Program" 79 means either the Program or any derivative work under copyright law: 80 that is to say, a work containing the Program or a portion of it, 81 either verbatim or with modifications and/or translated into another 82 language. (Hereinafter, translation is included without limitation in 83 the term "modification".) Each licensee is addressed as "you". 84 85 Activities other than copying, distribution and modification are not 86 covered by this License; they are outside its scope. The act of 87 running the Program is not restricted, and the output from the Program 88 is covered only if its contents constitute a work based on the 89 Program (independent of having been made by running the Program). 90 Whether that is true depends on what the Program does. 91 92 1. You may copy and distribute verbatim copies of the Program's 93 source code as you receive it, in any medium, provided that you 94 conspicuously and appropriately publish on each copy an appropriate 95 copyright notice and disclaimer of warranty; keep intact all the 96 notices that refer to this License and to the absence of any warranty; 97 and give any other recipients of the Program a copy of this License 98 along with the Program. 99 100 You may charge a fee for the physical act of transferring a copy, and 101 you may at your option offer warranty protection in exchange for a fee. 102 103 2. You may modify your copy or copies of the Program or any portion 104 of it, thus forming a work based on the Program, and copy and 105 distribute such modifications or work under the terms of Section 1 106 above, provided that you also meet all of these conditions: 107 108 a) You must cause the modified files to carry prominent notices 109 stating that you changed the files and the date of any change. 110 111 b) You must cause any work that you distribute or publish, that in 112 whole or in part contains or is derived from the Program or any 113 part thereof, to be licensed as a whole at no charge to all third 114 parties under the terms of this License. 115 116 c) If the modified program normally reads commands interactively 117 when run, you must cause it, when started running for such 118 interactive use in the most ordinary way, to print or display an 119 announcement including an appropriate copyright notice and a 120 notice that there is no warranty (or else, saying that you provide 121 a warranty) and that users may redistribute the program under 122 these conditions, and telling the user how to view a copy of this 123 License. (Exception: if the Program itself is interactive but 124 does not normally print such an announcement, your work based on 125 the Program is not required to print an announcement.) 126 128 These requirements apply to the modified work as a whole. If 129 identifiable sections of that work are not derived from the Program, 130 and can be reasonably considered independent and separate works in 131 themselves, then this License, and its terms, do not apply to those 132 sections when you distribute them as separate works. But when you 133 distribute the same sections as part of a whole which is a work based 134 on the Program, the distribution of the whole must be on the terms of 135 this License, whose permissions for other licensees extend to the 136 entire whole, and thus to each and every part regardless of who wrote it. 137 138 Thus, it is not the intent of this section to claim rights or contest 139 your rights to work written entirely by you; rather, the intent is to 140 exercise the right to control the distribution of derivative or 141 collective works based on the Program. 142 143 In addition, mere aggregation of another work not based on the Program 144 with the Program (or with a work based on the Program) on a volume of 145 a storage or distribution medium does not bring the other work under 146 the scope of this License. 147 148 3. You may copy and distribute the Program (or a work based on it, 149 under Section 2) in object code or executable form under the terms of 150 Sections 1 and 2 above provided that you also do one of the following: 151 152 a) Accompany it with the complete corresponding machine-readable 153 source code, which must be distributed under the terms of Sections 154 1 and 2 above on a medium customarily used for software interchange; or, 155 156 b) Accompany it with a written offer, valid for at least three 157 years, to give any third party, for a charge no more than your 158 cost of physically performing source distribution, a complete 159 machine-readable copy of the corresponding source code, to be 160 distributed under the terms of Sections 1 and 2 above on a medium 161 customarily used for software interchange; or, 162 163 c) Accompany it with the information you received as to the offer 164 to distribute corresponding source code. (This alternative is 165 allowed only for noncommercial distribution and only if you 166 received the program in object code or executable form with such 167 an offer, in accord with Subsection b above.) 168 169 The source code for a work means the preferred form of the work for 170 making modifications to it. For an executable work, complete source 171 code means all the source code for all modules it contains, plus any 172 associated interface definition files, plus the scripts used to 173 control compilation and installation of the executable. However, as a 174 special exception, the source code distributed need not include 175 anything that is normally distributed (in either source or binary 176 form) with the major components (compiler, kernel, and so on) of the 177 operating system on which the executable runs, unless that component 178 itself accompanies the executable. 179 180 If distribution of executable or object code is made by offering 181 access to copy from a designated place, then offering equivalent 182 access to copy the source code from the same place counts as 183 distribution of the source code, even though third parties are not 184 compelled to copy the source along with the object code. 185 187 4. You may not copy, modify, sublicense, or distribute the Program 188 except as expressly provided under this License. Any attempt 189 otherwise to copy, modify, sublicense or distribute the Program is 190 void, and will automatically terminate your rights under this License. 191 However, parties who have received copies, or rights, from you under 192 this License will not have their licenses terminated so long as such 193 parties remain in full compliance. 194 195 5. You are not required to accept this License, since you have not 196 signed it. However, nothing else grants you permission to modify or 197 distribute the Program or its derivative works. These actions are 198 prohibited by law if you do not accept this License. Therefore, by 199 modifying or distributing the Program (or any work based on the 200 Program), you indicate your acceptance of this License to do so, and 201 all its terms and conditions for copying, distributing or modifying 202 the Program or works based on it. 203 204 6. Each time you redistribute the Program (or any work based on the 205 Program), the recipient automatically receives a license from the 206 original licensor to copy, distribute or modify the Program subject to 207 these terms and conditions. You may not impose any further 208 restrictions on the recipients' exercise of the rights granted herein. 209 You are not responsible for enforcing compliance by third parties to 210 this License. 211 212 7. If, as a consequence of a court judgment or allegation of patent 213 infringement or for any other reason (not limited to patent issues), 214 conditions are imposed on you (whether by court order, agreement or 215 otherwise) that contradict the conditions of this License, they do not 216 excuse you from the conditions of this License. If you cannot 217 distribute so as to satisfy simultaneously your obligations under this 218 License and any other pertinent obligations, then as a consequence you 219 may not distribute the Program at all. For example, if a patent 220 license would not permit royalty-free redistribution of the Program by 221 all those who receive copies directly or indirectly through you, then 222 the only way you could satisfy both it and this License would be to 223 refrain entirely from distribution of the Program. 224 225 If any portion of this section is held invalid or unenforceable under 226 any particular circumstance, the balance of the section is intended to 227 apply and the section as a whole is intended to apply in other 228 circumstances. 229 230 It is not the purpose of this section to induce you to infringe any 231 patents or other property right claims or to contest validity of any 232 such claims; this section has the sole purpose of protecting the 233 integrity of the free software distribution system, which is 234 implemented by public license practices. Many people have made 235 generous contributions to the wide range of software distributed 236 through that system in reliance on consistent application of that 237 system; it is up to the author/donor to decide if he or she is willing 238 to distribute software through any other system and a licensee cannot 239 impose that choice. 240 241 This section is intended to make thoroughly clear what is believed to 242 be a consequence of the rest of this License. 243 245 8. If the distribution and/or use of the Program is restricted in 246 certain countries either by patents or by copyrighted interfaces, the 247 original copyright holder who places the Program under this License 248 may add an explicit geographical distribution limitation excluding 249 those countries, so that distribution is permitted only in or among 250 countries not thus excluded. In such case, this License incorporates 251 the limitation as if written in the body of this License. 252 253 9. The Free Software Foundation may publish revised and/or new versions 254 of the General Public License from time to time. Such new versions will 255 be similar in spirit to the present version, but may differ in detail to 256 address new problems or concerns. 257 258 Each version is given a distinguishing version number. If the Program 259 specifies a version number of this License which applies to it and "any 260 later version", you have the option of following the terms and conditions 261 either of that version or of any later version published by the Free 262 Software Foundation. If the Program does not specify a version number of 263 this License, you may choose any version ever published by the Free Software 264 Foundation. 265 266 10. If you wish to incorporate parts of the Program into other free 267 programs whose distribution conditions are different, write to the author 268 to ask for permission. For software which is copyrighted by the Free 269 Software Foundation, write to the Free Software Foundation; we sometimes 270 make exceptions for this. Our decision will be guided by the two goals 271 of preserving the free status of all derivatives of our free software and 272 of promoting the sharing and reuse of software generally. 273 274 NO WARRANTY 275 276 11. BECAUSE THE PROGRAM IS LICENSED FREE OF CHARGE, THERE IS NO WARRANTY 277 FOR THE PROGRAM, TO THE EXTENT PERMITTED BY APPLICABLE LAW. EXCEPT WHEN 278 OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES 279 PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED 280 OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 281 MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE ENTIRE RISK AS 282 TO THE QUALITY AND PERFORMANCE OF THE PROGRAM IS WITH YOU. SHOULD THE 283 PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF ALL NECESSARY SERVICING, 284 REPAIR OR CORRECTION. 285 286 12. IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING 287 WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MAY MODIFY AND/OR 288 REDISTRIBUTE THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, 289 INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING 290 OUT OF THE USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED 291 TO LOSS OF DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY 292 YOU OR THIRD PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER 293 PROGRAMS), EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE 294 POSSIBILITY OF SUCH DAMAGES. 295 296 END OF TERMS AND CONDITIONS 297 299 Appendix: How to Apply These Terms to Your New Programs 300 301 If you develop a new program, and you want it to be of the greatest 302 possible use to the public, the best way to achieve this is to make it 303 free software which everyone can redistribute and change under these terms. 304 305 To do so, attach the following notices to the program. It is safest 306 to attach them to the start of each source file to most effectively 307 convey the exclusion of warranty; and each file should have at least 308 the "copyright" line and a pointer to where the full notice is found. 309 310 <one line to give the program's name and a brief idea of what it does.> 311 Copyright (C) 19yy <name of author> 312 313 This program is free software; you can redistribute it and/or modify 314 it under the terms of the GNU General Public License as published by 315 the Free Software Foundation; either version 2 of the License, or 316 (at your option) any later version. 317 318 This program is distributed in the hope that it will be useful, 319 but WITHOUT ANY WARRANTY; without even the implied warranty of 320 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 321 GNU General Public License for more details. 322 323 You should have received a copy of the GNU General Public License 324 along with this program; if not, write to the Free Software 325 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. 326 327 Also add information on how to contact you by electronic and paper mail. 328 329 If the program is interactive, make it output a short notice like this 330 when it starts in an interactive mode: 331 332 Gnomovision version 69, Copyright (C) 19yy name of author 333 Gnomovision comes with ABSOLUTELY NO WARRANTY; for details type `show w'. 334 This is free software, and you are welcome to redistribute it 335 under certain conditions; type `show c' for details. 336 337 The hypothetical commands `show w' and `show c' should show the appropriate 338 parts of the General Public License. Of course, the commands you use may 339 be called something other than `show w' and `show c'; they could even be 340 mouse-clicks or menu items--whatever suits your program. 341 342 You should also get your employer (if you work as a programmer) or your 343 school, if any, to sign a "copyright disclaimer" for the program, if 344 necessary. Here is a sample; alter the names: 345 346 Yoyodyne, Inc., hereby disclaims all copyright interest in the program 347 `Gnomovision' (which makes passes at compilers) written by James Hacker. 348 349 <signature of Ty Coon>, 1 April 1989 350 Ty Coon, President of Vice 351 352 This General Public License does not permit incorporating your program into 353 proprietary programs. If your program is a subroutine library, you may 354 consider it more useful to permit linking proprietary applications with the 355 library. If this is what you want to do, use the GNU Library General 356 Public License instead of this License. 357