I
License Statement
GPL
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 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 Lesser 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.
