Version 2, June 1991 Copyright (C) 1989, 1991 Free Software Foundation, Inc. 59 Temple Place - Suite
330, Boston, MA 02111-1307, 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
