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.
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.
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.
3. 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:
-
- 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,
-
- 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,
-
- 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.)
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.
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.
4. 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.
5. 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.
6. 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.
7. 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.
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.
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.
This section is intended to
make thoroughly clear what is believed to be a consequence of the rest
of this License.
8. 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.
9. 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.
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.
10. 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.
NO WARRANTY
11.
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.
12. 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.
END OF TERMS AND
CONDITIONS
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