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Appendix B Gnu General Public License
Gnu General Public License
Version 2, June 1991
Copyright (C) 1989, 1991 Free Software Foundati on, Inc.
59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
Everyoneis permitted to copy and distribute verbatim copies of this
license document, but changing it is not allowed.
Preamble
Theli censes for most software are designed to take away your freedom to
share and change it. Byco ntrast, the GNU General Public License is
intended to guarantee your freedom to share and change free software
to make sure thes oftwareis free for all its users. This General Public
License applies to most of the Free Software Foundation's software an d
to any other program whose authors commit to using it. (Some other
Free Software Foundation software is covered by the GNU Lib rary
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
thatyouknowyoucandothesethings.
To protect your rights, we need to make restriction s that forbid anyone to
deny you these rights or to ask you to surrender the rights. These
restrictionstranslate to certain responsibilities for you if you distribute
copies ofthe software, or if you modify it.
For example, if you distribute copies of such a program, whe ther 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)
offeryou this license which gives you legal permission to copy, distribute
and/or modify the software.
Also, for each author'sprotection and ours, we want to make certain that
everyone understands that there is no warranty for this fr ee software. If
the softwareis modified by someone else and passed on, we want its
recipientsto know that what they have is not the original, so that any
problemsintroduced by others will not reflect on the original authors'
reputations.
Finally, anyfree program is threatened constantly by software patents.
We wish to avoid the danger that redistributors of a free progra m will
individually obtain patent licenses, in effect making the program
proprietary. Toprev ent this, we have made it clear that any patent must
be licensedfor everyone's free use or not licensed at all.
The precise termsand conditions for copying, distribution and
modificationfollow.
GNU GENERAL PUBLIC LICENSE
Terms andconditions for copying, distribution and modification.
0. This Licenseapplies to any program or other work which contains a
noticeplaced by the copyright holder saying it may be distributed under
the terms ofthis General Public License. The Program,below, refers
to any such program or work, and a workbasedontheProgrammeans