English - 98The GNU General Public License (GPL)Version 2, June 1991Copyright (C) 1989, 1991 Free Software Foundation, Inc. 59 Temple Place, Suite 330, Boston, MA 02111-1307 USAEveryone is permitted to copy and distribute verbatim copies of this license document, but changing it is not allowed.PreambleThe licenses for most software are designed to take away your freedom to share and change it. By contrast, the GNUGeneral Public License is intended to guarantee your freedom to share and change free software--to make sure thesoftware is free for all its users. This General Public License applies to most of the Free Software Foundation’s software andto any other program whose authors commit to using it. (Some other Free Software Foundation software is covered by theGNU 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 tomake sure that you have the freedom to distribute copies of free software (and charge for this service if you wish), that youreceive 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 th at 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 surrenderthe rights. These restrictions translate to certain responsibilities for you if you distribute copies of the software, or if youmodify it.For example, if you distribute copies of such a program, whether gratis or for a fee, you must give the recipients all therights that you have. You must make sure that they, too, receive or can get the source code. And you must show them theseterms 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 legalpermission 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 forthis free software. If the software is modied by someone else and passed on, we want its recipients to know that what theyhave is not the original, so that any problems introduced by others will not re ect on the original authors’ reputations.Finally, any free program is threatened constantly by software patents. We wish to avoid the danger that redistributors of afree program will individually obtain patent licenses, in effect making the program proprietary. To prevent this, we have madeit 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 modication follow.TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION0. This License applies to any program or other work which contains a notice placed by the copyright holder saying it maybe 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, awork containing the Program or a portion of it, either verbatim or with modications and/or translated into another language.(Hereinafter, translation is included without limitation in the term “modication”.) Each licensee is addressed as “you”.Activities other than copying, distribution and modication are not covered by this License; they are outside its scope. Theact of running the Program is not restricted, and the output from the Program is covered only if its contents constitute a workbased on the Program (independent of having been made by running the Program). Whether that is true depends on whatthe Program does.1. You may copy and distribute verbatim copies of the Program’s source code as you receive it, in any medium, providedthat 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 theProgram 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 inexchange 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, andcopy and distribute such modications or work under the terms of Section 1 above, provided that you also meet all of theseconditions:a) You must cause the modied les to carry prominent notices stating that you changed the les and the date of anychange.b) You must cause any work that you distribute or publish, that in whole or in part contains or is derived from theProgram 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 modied program normally reads commands interactively when run, you must cause it, when started runningfor such interactive use in the most ordinary way, to print or display an announcement including an appropriatecopyright notice and a notice that there is no warranty (or else, saying that you provide a warranty) and that users mayredistribute the program under these conditions, and telling the user how to view a copy of this License. (Exception: ifthe Program itself is interactive but does not normally print such an announcement, your work based on the Program isnot required to print an announcement.)