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.