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)
<year> <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) year 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.