GNU GENERAL PUBLIC LICENSE
Version 2, June 1991
Copyright (C) 1989, 1991 Free Software
Foundation, Inc. 59 Temple Place, Suite
330, Boston, MA 02111-1307 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 Library 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.
GNU GENERAL PUBLIC LICENSE
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
How to Apply These Terms to Your New
Programs
If you develop a new program, and you want it
to be of the greatest possible use to the public,
the best way to achieve this is to make it free
software which everyone can redistribute and
change under these terms.
To do so, attach the following notices to the
program. It is safest to attach them to the
start of each source file to most effectively
convey the exclusion of warranty; and each file
should have at least the "copyright" line and a
pointer to where the full notice is found.
<one line to give the program's name and a
brief idea of what it does.> Copyright (C)
yyyy <name of author>
This program is free software; you can
redistribute it and/or modify it under the
terms of the GNU General Public License as
published by the Free Software Foundation;
either version 2 of the License, or (at your
option) any later version.
This program is distributed in the hope that
it will be useful, but WITHOUT ANY WARRANTY;
without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR
PURPOSE. See the GNU General Public License
for more details.
You should have received a copy of the GNU
General Public License along with this
program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330,
Boston, MA 02111-1307 USA
Also add information on how to contact you by
electronic and paper mail.
If the program is interactive, make it output a
short notice like this when it starts in an
interactive mode:
Gnomovision version 69, Copyright (C) yyyy
name of author Gnomovision comes with
ABSOLUTELY NO WARRANTY; for details type
`show w'. This is free software, and you are
welcome to redistribute it under certain
conditions; type `show c' for details.
The hypothetical commands `show w' and `show c'
should show the appropriate parts of the General
Public License. Of course, the commands you use
may be called something other than `show w' and
`show c'; they could even be mouse-clicks or menu
items--whatever suits your program.
You should also get your employer (if you work as
a programmer) or your school, if any, to sign a
"copyright disclaimer" for the program, if
necessary. Here is a sample; alter the names:
Yoyodyne, Inc., hereby disclaims all copyright
interest in the program `Gnomovision' (which
makes passes at compilers) written by James
Hacker.
<signature of Ty Coon>, 1 April 1989
Ty Coon, President of Vice
This General Public License does not permit
incorporating your program into proprietary
programs. If your program is a subroutine
library, you may consider it more useful to
permit linking proprietary applications with the
library. If this is what you want to do, use the
GNU Library General Public License instead of
this License.