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