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<title>GNU General Public License, version 2 (GPLv2) | Open Source Initiative</title>
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<h1>The GNU General Public License (GPL)</h1>
<h2>Version 2, June 1991</h2>
<p>Copyright (C) 1989, 1991 Free Software Foundation, Inc.<br />
59 Temple Place, Suite 330, Boston, MA 02111-1307 USA</p>
<p>Everyone is permitted to copy and distribute verbatim copies<br />
of this license document, but changing it is not allowed.</p>
<p><strong>Preamble</strong></p>
<p>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.</p>
<p>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.</p>
<p>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.</p>
<p>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.</p>
<p>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.</p>
<p>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.</p>
<p>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.</p>
<p>The precise terms and conditions for copying, distribution and modification follow.</p>
<p><strong>TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION</strong></p>
<p><strong>0</strong>. 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".</p>
<p>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.</p>
<p><strong>1</strong>. 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.</p>
<p>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.</p>
<p><strong>2</strong>. 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:</p>
<blockquote>
<p>a) You must cause the modified files to carry prominent notices stating that you changed the files and the date of any change.</p>
<p>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.</p>
<p>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.)</p>
</blockquote>
<p>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.</p>
<p>Thus, it is not the intent of this section to claim rights or
contest your rights to work written entirely by you; rather, the intent
is to exercise the right to control the distribution of derivative or
collective works based on the Program.</p>
<p>In addition, mere aggregation of another work not based on the
Program with the Program (or with a work based on the Program) on a
volume of a storage or distribution medium does not bring the other work
under the scope of this License.</p>
<p><strong>3</strong>. You may copy and distribute the Program (or a
work based on it, under Section 2) in object code or executable form
under the terms of Sections 1 and 2 above provided that you also do one
of the following:</p>
<blockquote>
<p>a) Accompany it with the complete corresponding
machine-readable source code, which must be distributed under the terms
of Sections 1 and 2 above on a medium customarily used for software
interchange; or,</p>
<p>b) Accompany it with a written offer, valid for at least three
years, to give any third party, for a charge no more than your cost of
physically performing source distribution, a complete machine-readable
copy of the corresponding source code, to be distributed under the terms
of Sections 1 and 2 above on a medium customarily used for software
interchange; or,</p>
<p>c) Accompany it with the information you received as to the
offer to distribute corresponding source code. (This alternative is
allowed only for noncommercial distribution and only if you received the
program in object code or executable form with such an offer, in accord
with Subsection b above.)</p>
</blockquote>
<p>The source code for a work means the preferred form of the work
for making modifications to it. For an executable work, complete source
code means all the source code for all modules it contains, plus any
associated interface definition files, plus the scripts used to control
compilation and installation of the executable. However, as a special
exception, the source code distributed need not include anything that is
normally distributed (in either source or binary form) with the major
components (compiler, kernel, and so on) of the operating system on
which the executable runs, unless that component itself accompanies the
executable.</p>
<p>If distribution of executable or object code is made by offering
access to copy from a designated place, then offering equivalent access
to copy the source code from the same place counts as distribution of
the source code, even though third parties are not compelled to copy the
source along with the object code.</p>
<p><strong>4</strong>. You may not copy, modify, sublicense, or
distribute the Program except as expressly provided under this License.
Any attempt otherwise to copy, modify, sublicense or distribute the
Program is void, and will automatically terminate your rights under this
License. However, parties who have received copies, or rights, from you
under this License will not have their licenses terminated so long as
such parties remain in full compliance.</p>
<p><strong>5</strong>. You are not required to accept this License,
since you have not signed it. However, nothing else grants you
permission to modify or distribute the Program or its derivative works.
These actions are prohibited by law if you do not accept this License.
Therefore, by modifying or distributing the Program (or any work based
on the Program), you indicate your acceptance of this License to do so,
and all its terms and conditions for copying, distributing or modifying
the Program or works based on it.</p>
<p><strong>6</strong>. Each time you redistribute the Program (or
any work based on the Program), the recipient automatically receives a
license from the original licensor to copy, distribute or modify the
Program subject to these terms and conditions. You may not impose any
further restrictions on the recipients' exercise of the rights granted
herein. You are not responsible for enforcing compliance by third
parties to this License.</p>
<p><strong>7</strong>. If, as a consequence of a court judgment or
allegation of patent infringement or for any other reason (not limited
to patent issues), conditions are imposed on you (whether by court
order, agreement or otherwise) that contradict the conditions of this
License, they do not excuse you from the conditions of this License. If
you cannot distribute so as to satisfy simultaneously your obligations
under this License and any other pertinent obligations, then as a
consequence you may not distribute the Program at all. For example, if a
patent license would not permit royalty-free redistribution of the
Program by all those who receive copies directly or indirectly through
you, then the only way you could satisfy both it and this License would
be to refrain entirely from distribution of the Program.</p>
<p>If any portion of this section is held invalid or unenforceable
under any particular circumstance, the balance of the section is
intended to apply and the section as a whole is intended to apply in
other circumstances.</p>
<p>It is not the purpose of this section to induce you to infringe
any patents or other property right claims or to contest validity of any
such claims; this section has the sole purpose of protecting the
integrity of the free software distribution system, which is implemented
by public license practices. Many people have made generous
contributions to the wide range of software distributed through that
system in reliance on consistent application of that system; it is up to
the author/donor to decide if he or she is willing to distribute
software through any other system and a licensee cannot impose that
choice.</p>
<p>This section is intended to make thoroughly clear what is believed to be a consequence of the rest of this License.</p>
<p><strong>8</strong>. If the distribution and/or use of the Program
is restricted in certain countries either by patents or by copyrighted
interfaces, the original copyright holder who places the Program under
this License may add an explicit geographical distribution limitation
excluding those countries, so that distribution is permitted only in or
among countries not thus excluded. In such case, this License
incorporates the limitation as if written in the body of this License.</p>
<p><strong>9</strong>. The Free Software Foundation may publish
revised and/or new versions of the General Public License from time to
time. Such new versions will be similar in spirit to the present
version, but may differ in detail to address new problems or concerns.</p>
<p>Each version is given a distinguishing version number. If the
Program specifies a version number of this License which applies to it
and "any later version", you have the option of following the terms and
conditions either of that version or of any later version published by
the Free Software Foundation. If the Program does not specify a version
number of this License, you may choose any version ever published by the
Free Software Foundation.</p>
<p><strong>10</strong>. If you wish to incorporate parts of the
Program into other free programs whose distribution conditions are
different, write to the author to ask for permission. For software which
is copyrighted by the Free Software Foundation, write to the Free
Software Foundation; we sometimes make exceptions for this. Our decision
will be guided by the two goals of preserving the free status of all
derivatives of our free software and of promoting the sharing and reuse
of software generally.</p>
<p><strong>NO WARRANTY</strong></p>
<p><strong>11</strong>. BECAUSE THE PROGRAM IS LICENSED FREE OF
CHARGE, THERE IS NO WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY
APPLICABLE LAW. EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT
HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM "AS IS" WITHOUT
WARRANTY OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT
LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
PARTICULAR PURPOSE. THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF
THE PROGRAM IS WITH YOU. SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME
THE COST OF ALL NECESSARY SERVICING, REPAIR OR CORRECTION.</p>
<p><strong>12</strong>. IN NO EVENT UNLESS REQUIRED BY APPLICABLE
LAW OR AGREED TO IN WRITING WILL ANY COPYRIGHT HOLDER, OR ANY OTHER
PARTY WHO MAY MODIFY AND/OR REDISTRIBUTE THE PROGRAM AS PERMITTED ABOVE,
BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY GENERAL, SPECIAL,
INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE USE OR INABILITY
TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF DATA OR DATA
BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD PARTIES OR
A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS), EVEN IF
SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
DAMAGES.</p>
<p>END OF TERMS AND CONDITIONS</p>
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