| # The GNU General Public License, Version 2, June 1991 (GPLv2) | |
| > Copyright (C) 1989, 1991 Free Software Foundation, Inc. | |
| > 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA | |
| Everyone is permitted to copy and distribute verbatim copies of this license | |
| document, but changing it is not allowed. | |
| ## Preamble | |
| The licenses for most software are designed to take away your freedom to share | |
| and change it. By contrast, the GNU General Public License is intended to | |
| guarantee your freedom to share and change free software--to make sure the | |
| software is free for all its users. This General Public License applies to most | |
| of the Free Software Foundation's software and to any other program whose | |
| authors commit to using it. (Some other Free Software Foundation software is | |
| covered by the GNU Library General Public License instead.) You can apply it to | |
| your programs, too. | |
| When we speak of free software, we are referring to freedom, not price. Our | |
| General Public Licenses are designed to make sure that you have the freedom to | |
| distribute copies of free software (and charge for this service if you wish), | |
| that you receive source code or can get it if you want it, that you can change | |
| the software or use pieces of it in new free programs; and that you know you can | |
| do these things. | |
| To protect your rights, we need to make restrictions that forbid anyone to deny | |
| you these rights or to ask you to surrender the rights. These restrictions | |
| translate to certain responsibilities for you if you distribute copies of the | |
| software, or if you modify it. | |
| For example, if you distribute copies of such a program, whether gratis or for a | |
| fee, you must give the recipients all the rights that you have. You must make | |
| sure that they, too, receive or can get the source code. And you must show them | |
| these terms so they know their rights. | |
| We protect your rights with two steps: (1) copyright the software, and (2) offer | |
| you this license which gives you legal permission to copy, distribute and/or | |
| modify the software. | |
| Also, for each author's protection and ours, we want to make certain that | |
| everyone understands that there is no warranty for this free software. If the | |
| software is modified by someone else and passed on, we want its recipients to | |
| know that what they have is not the original, so that any problems introduced by | |
| others will not reflect on the original authors' reputations. | |
| Finally, any free program is threatened constantly by software patents. We wish | |
| to avoid the danger that redistributors of a free program will individually | |
| obtain patent licenses, in effect making the program proprietary. To prevent | |
| this, we have made it clear that any patent must be licensed for everyone's free | |
| use or not licensed at all. | |
| The precise terms and conditions for copying, distribution and modification | |
| follow. | |
| ## Terms And Conditions For Copying, Distribution And Modification | |
| **0.** This License applies to any program or other work which contains a notice | |
| placed by the copyright holder saying it may be distributed under the terms of | |
| this General Public License. The "Program", below, refers to any such program or | |
| work, and a "work based on the Program" means either the Program or any | |
| derivative work under copyright law: that is to say, a work containing the | |
| Program or a portion of it, either verbatim or with modifications and/or | |
| translated into another language. (Hereinafter, translation is included without | |
| limitation in the term "modification".) Each licensee is addressed as "you". | |
| Activities other than copying, distribution and modification are not covered by | |
| this License; they are outside its scope. The act of running the Program is not | |
| restricted, and the output from the Program is covered only if its contents | |
| constitute a work based on the Program (independent of having been made by | |
| running the Program). Whether that is true depends on what the Program does. | |
| **1.** You may copy and distribute verbatim copies of the Program's source code | |
| as you receive it, in any medium, provided that you conspicuously and | |
| appropriately publish on each copy an appropriate copyright notice and | |
| disclaimer of warranty; keep intact all the notices that refer to this License | |
| and to the absence of any warranty; and give any other recipients of the Program | |
| a copy of this License along with the Program. | |
| You may charge a fee for the physical act of transferring a copy, and you may at | |
| your option offer warranty protection in exchange for a fee. | |
| **2.** You may modify your copy or copies of the Program or any portion of it, | |
| thus forming a work based on the Program, and copy and distribute such | |
| modifications or work under the terms of Section 1 above, provided that you also | |
| meet all of these conditions: | |
| - **a)** You must cause the modified files to carry prominent notices stating | |
| that you changed the files and the date of any change. | |
| - **b)** You must cause any work that you distribute or publish, that in whole | |
| or in part contains or is derived from the Program or any part thereof, to | |
| be licensed as a whole at no charge to all third parties under the terms of | |
| this License. | |
| - **c)** If the modified program normally reads commands interactively when | |
| run, you must cause it, when started running for such interactive use in the | |
| most ordinary way, to print or display an announcement including an | |
| appropriate copyright notice and a notice that there is no warranty (or | |
| else, saying that you provide a warranty) and that users may redistribute | |
| the program under these conditions, and telling the user how to view a copy | |
| of this License. (Exception: if the Program itself is interactive but does | |
| not normally print such an announcement, your work based on the Program is | |
| not required to print an announcement.) | |
| These requirements apply to the modified work as a whole. If identifiable | |
| sections of that work are not derived from the Program, and can be reasonably | |
| considered independent and separate works in themselves, then this License, and | |
| its terms, do not apply to those sections when you distribute them as separate | |
| works. But when you distribute the same sections as part of a whole which is a | |
| work based on the Program, the distribution of the whole must be on the terms of | |
| this License, whose permissions for other licensees extend to the entire whole, | |
| and thus to each and every part regardless of who wrote it. | |
| Thus, it is not the intent of this section to claim rights or contest your | |
| rights to work written entirely by you; rather, the intent is to exercise the | |
| right to control the distribution of derivative or collective works based on the | |
| Program. | |
| In addition, mere aggregation of another work not based on the Program with the | |
| Program (or with a work based on the Program) on a volume of a storage or | |
| distribution medium does not bring the other work under the scope of this | |
| License. | |
| **3.** You may copy and distribute the Program (or a work based on it, under | |
| Section 2) in object code or executable form under the terms of Sections 1 and 2 | |
| above provided that you also do one of the following: | |
| - **a)** Accompany it with the complete corresponding machine-readable source | |
| code, which must be distributed under the terms of Sections 1 and 2 above on | |
| a medium customarily used for software interchange; or, | |
| - **b)** Accompany it with a written offer, valid for at least three years, to | |
| give any third party, for a charge no more than your cost of physically | |
| performing source distribution, a complete machine-readable copy of the | |
| corresponding source code, to be distributed under the terms of Sections 1 | |
| and 2 above on a medium customarily used for software interchange; or, | |
| - **c)** Accompany it with the information you received as to the offer to | |
| distribute corresponding source code. (This alternative is allowed only for | |
| noncommercial distribution and only if you received the program in object | |
| code or executable form with such an offer, in accord with Subsection b | |
| above.) | |
| The source code for a work means the preferred form of the work for making | |
| modifications to it. For an executable work, complete source code means all the | |
| source code for all modules it contains, plus any associated interface | |
| definition files, plus the scripts used to control compilation and installation | |
| of the executable. However, as a special exception, the source code distributed | |
| need not include anything that is normally distributed (in either source or | |
| binary form) with the major components (compiler, kernel, and so on) of the | |
| operating system on which the executable runs, unless that component itself | |
| accompanies the executable. | |
| If distribution of executable or object code is made by offering access to copy | |
| from a designated place, then offering equivalent access to copy the source code | |
| from the same place counts as distribution of the source code, even though third | |
| parties are not compelled to copy the source along with the object code. | |
| **4.** You may not copy, modify, sublicense, or distribute the Program except as | |
| expressly provided under this License. Any attempt otherwise to copy, modify, | |
| sublicense or distribute the Program is void, and will automatically terminate | |
| your rights under this License. However, parties who have received copies, or | |
| rights, from you under this License will not have their licenses terminated so | |
| long as such parties remain in full compliance. | |
| **5.** You are not required to accept this License, since you have not signed | |
| it. However, nothing else grants you permission to modify or distribute the | |
| Program or its derivative works. These actions are prohibited by law if you do | |
| not accept this License. Therefore, by modifying or distributing the Program (or | |
| any work based on the Program), you indicate your acceptance of this License to | |
| do so, and all its terms and conditions for copying, distributing or modifying | |
| the Program or works based on it. | |
| **6.** Each time you redistribute the Program (or any work based on the | |
| Program), the recipient automatically receives a license from the original | |
| licensor to copy, distribute or modify the Program subject to these terms and | |
| conditions. You may not impose any further restrictions on the recipients' | |
| exercise of the rights granted herein. You are not responsible for enforcing | |
| compliance by third parties to this License. | |
| **7.** If, as a consequence of a court judgment or allegation of patent | |
| infringement or for any other reason (not limited to patent issues), conditions | |
| are imposed on you (whether by court order, agreement or otherwise) that | |
| contradict the conditions of this License, they do not excuse you from the | |
| conditions of this License. If you cannot distribute so as to satisfy | |
| simultaneously your obligations under this License and any other pertinent | |
| obligations, then as a consequence you may not distribute the Program at all. | |
| For example, if a patent license would not permit royalty-free redistribution of | |
| the Program by all those who receive copies directly or indirectly through you, | |
| then the only way you could satisfy both it and this License would be to refrain | |
| entirely from distribution of the Program. | |
| If any portion of this section is held invalid or unenforceable under any | |
| particular circumstance, the balance of the section is intended to apply and the | |
| section as a whole is intended to apply in other circumstances. | |
| It is not the purpose of this section to induce you to infringe any patents or | |
| other property right claims or to contest validity of any such claims; this | |
| section has the sole purpose of protecting the integrity of the free software | |
| distribution system, which is implemented by public license practices. Many | |
| people have made generous contributions to the wide range of software | |
| distributed through that system in reliance on consistent application of that | |
| system; it is up to the author/donor to decide if he or she is willing to | |
| distribute software through any other system and a licensee cannot impose that | |
| choice. | |
| This section is intended to make thoroughly clear what is believed to be a | |
| consequence of the rest of this License. | |
| **8.** If the distribution and/or use of the Program is restricted in certain | |
| countries either by patents or by copyrighted interfaces, the original copyright | |
| holder who places the Program under this License may add an explicit | |
| geographical distribution limitation excluding those countries, so that | |
| distribution is permitted only in or among countries not thus excluded. In such | |
| case, this License incorporates the limitation as if written in the body of this | |
| License. | |
| **9.** The Free Software Foundation may publish revised and/or new versions of | |
| the General Public License from time to time. Such new versions will be similar | |
| in spirit to the present version, but may differ in detail to address new | |
| problems or concerns. | |
| Each version is given a distinguishing version number. If the Program specifies | |
| a version number of this License which applies to it and "any later version", | |
| you have the option of following the terms and conditions either of that version | |
| or of any later version published by the Free Software Foundation. If the | |
| Program does not specify a version number of this License, you may choose any | |
| version ever published by the Free Software Foundation. | |
| **10.** If you wish to incorporate parts of the Program into other free programs | |
| whose distribution conditions are different, write to the author to ask for | |
| permission. For software which is copyrighted by the Free Software Foundation, | |
| write to the Free Software Foundation; we sometimes make exceptions for this. | |
| Our decision will be guided by the two goals of preserving the free status of | |
| all derivatives of our free software and of promoting the sharing and reuse of | |
| software generally. | |
| ## No Warranty | |
| **11.** BECAUSE THE PROGRAM IS LICENSED FREE OF CHARGE, THERE IS NO WARRANTY FOR | |
| THE PROGRAM, TO THE EXTENT PERMITTED BY APPLICABLE LAW. EXCEPT WHEN OTHERWISE | |
| STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM | |
| "AS IS" WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, | |
| BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A | |
| PARTICULAR PURPOSE. THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE | |
| PROGRAM IS WITH YOU. SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF | |
| ALL NECESSARY SERVICING, REPAIR OR CORRECTION. | |
| **12.** IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING | |
| WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MAY MODIFY AND/OR REDISTRIBUTE | |
| THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY | |
| GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE USE OR | |
| INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF DATA OR DATA | |
| BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD PARTIES OR A | |
| FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS), EVEN IF SUCH HOLDER | |
| OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES. | |