Version 2, June 1991
2000Free Software Foundation, Inc.
Free Software Foundation, Inc.
51 Franklin Street, Fifth Floor,
Boston,
MA02110-1335USA
Everyone is permitted to copy and distribute verbatim copies
of this license document, but changing it is not allowed.
GNU General Public LicensePreamble
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:
copyright the software, and
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 MODIFICATIONSection 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.
Section 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.
Section 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:
You must cause the modified files to carry prominent
notices stating that you changed the files and the date
of any change.
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.
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.
Section 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:
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,
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,
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.
Section 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.
Section 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.
Section 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.
Section 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.
Section 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.
Section 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.
Section 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 WARRANTYSection 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.
Section 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.