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GNU GENERAL PUBLIC LICENSE
Version 2, June 1991
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 Li-
cense 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 us-
ing it. (Some other Free Software Foundation
software is covered by the GNU Lesser General
Public License instead.) You can apply it to your
programs, too.
When we speak of free software, we are refer-
ring 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 re-
strictions that forbid anyone to deny you these
rights or to ask you to surrender the rights.
These restrictions translate to certain respon-
sibilities 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 li
-
cense 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 under-
stands that there is no warranty for this free
software. If the software is modi
fi
ed by some
-
one 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 re
fl
ect on the original authors' reputations.
Finally, any free program is threatened con-
stantly 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 modi
fi
cation follow.
GNU GENERAL PUBLIC LICENSE
TERMS AND CONDITIONS FOR COPYING,
DISTRIBUTION AND MODIFICATION
0. This License applies to any program or oth-
er 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 pro-
gram or work, and a "work based on the Pro-
gram" means either the Program or any deriva-
tive work under copyright law: that is to say, a
work containing the Program or a portion of it,
either verbatim or with modi
fi
cations and/or
translated into another language. (Hereinafter,
translation is included without limitation in the
term "modi
fi
cation".) Each licensee is addressed
as "you".
Activities other than copying, distribution and
modi
fi
cation 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 con-
tents 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 cop-
ies of the Program's source code as you receive
it, in any medium, provided that you conspicu-
ously and appropriately publish on each copy
