PERLGPL(1) Perl Programmers Reference Guide PERLGPL(1)NAMEperlgpl - the GNU General Public License, version 2
SYNOPSIS
You can refer to this document in Pod via "L<perlgpl>"
Or you can see this document by entering "perldoc perlgpl"
DESCRIPTION
This is "The GNU General Public License, version 2". It's
here so that modules, programs, etc., that want to declare
this as their distribution license, can link to it.
It is also one of the two licenses Perl allows itself to be
redistributed and/or modified; for the other one, the Perl
Artistic License, see the perlartistic.
GNU GENERAL PUBLIC LICENSE
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 pro-
grams; 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 cer-
tain responsibilities for you if you distribute copies of
the software, or if you modify it.
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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 prob-
lems 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 redis-
tributors 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 licen-
see 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 con-
stitute a work based on the Program (independent of having
been made by running the Program). Whether that is true
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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, pro-
vided 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
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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 defini-
tion 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 any-
thing 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 execut-
able.
If distribution of executable or object code is made by
offering access to copy from a designated place, then offer-
ing equivalent access to copy the source code from the same
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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 distri-
bute 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 per-
mission to modify or distribute the Program or its deriva-
tive works. These actions are prohibited by law if you do
not accept this License. Therefore, by modifying or distri-
buting 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 modi-
fying 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 reci-
pients' 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 unenforce-
able under any particular circumstance, the balance of the
section is intended to apply and the section as a whole is
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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 contribu-
tions 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 wil-
ling 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 res-
tricted in certain countries either by patents or by copy-
righted interfaces, the original copyright holder who places
the Program under this License may add an explicit geograph-
ical 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 Foun-
dation. 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 dif-
ferent, write to the author to ask for permission. For
software which is copyrighted by the Free Software Founda-
tion, 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 deriva-
tives of our free software and of promoting the sharing and
reuse of software generally.
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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 WARRAN-
TIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PUR-
POSE. THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF
THE PROGRAM IS WITH YOU. SHOULD THE PROGRAM PROVE DEFEC-
TIVE, 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
--
Appendix: 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 redis-
tribute 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) 19yy <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.
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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) 19yy 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 program-
mer) or your school, if any, to sign a "copyright disclai-
mer" 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.
[End.]
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