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Swish-e License

This is the Swish-e License. A copy of this license appears in the COPYING file with the distribution.
Swish-e 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.

See below for version 2 of the GNU GPL.

Unless otherwise indicated, all source files are 
Copyright (C) 2005, the Swish-e Project, http://swish-e.org.

Swish-e includes a library for searching with a well-defined API. The library
is named libswish-e.

Linking libswish-e statically or dynamically with other modules is making a
combined work based on Swish-e.  Thus, the terms and conditions of the GNU
General Public License cover the whole combination.

As a special exception, the copyright holders of Swish-e give you
permission to link Swish-e with independent modules that communicate with
Swish-e solely through the libswish-e API interface, regardless of the 
license terms of these independent modules, and to copy and distribute the
resulting combined work under terms of your choice, provided that
every copy of the combined work is accompanied by, or provides a URL link to,
a complete copy of the source code of Swish-e 
(the version of Swish-e used to produce the combined work), 
being distributed under the terms of the GNU General
Public License plus this exception.  An independent module is a module
which is not derived from or based on Swish-e.

Note that people who make modified versions of Swish-e are not obligated
to grant this special exception for their modified versions; it is
their choice whether to do so.  The GNU General Public License gives
permission to release a modified version without this exception; this
exception also makes it possible to release a modified version which
carries forward this exception.



                    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
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    b) You must cause any work that you distribute or publish, that in
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    c) If the modified program normally reads commands interactively
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These requirements apply to the modified work as a whole.  If
identifiable sections of that work are not derived from the Program,
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Thus, it is not the intent of this section to claim rights or contest
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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
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  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
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    received the program in object code or executable form with such
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The source code for a work means the preferred form of the work for
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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
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  5. You are not required to accept this License, since you have not
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distribute the Program or its derivative works.  These actions are
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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
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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
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excuse you from the conditions of this License.  If you cannot
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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
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It is not the purpose of this section to induce you to infringe any
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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
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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
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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
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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.

Frequently Asked Questions about the Swish-e License

So what's the deal with the special exception to the standard GPL?

The GNU GPL allows for a special exception to the "tainting" behaviour of the GPL. See http://www.gnu.org/licenses/gpl-faq.html#LinkingOverControlledInterface for the official description.

In order to settle some ambiguities within the Swish-e source code, the developers decided to switch from the LGPL license under which Swish-e had originally been released to the standard GPL license. This is allowed (and often encouraged) under both licenses.

However, in order to allow other software projects to continue to link against the Swish-e searching library (libswish-e) and to continue to give other open source projects the freedom to use their own open source licenses, the special exception clause was invoked. This clause makes the Swish-e library and its API available under similar terms to the original LGPL, while putting the entire Swish-e project under the umbrella of the GPL.

We know this kind of legal hairsplitting can appear clever and needlessly subtle. The developers tend to agree. The developers also want to protect ten years of community effort from being used in closed, proprietary ways, while still allowing other open source efforts the freedom to use non-GPL licenses. Hence this compromise.

Contact the Swish-e discussion list with any questions about the Swish-e license.

I want to develop a new API interface to Swish-e in [insert your favorite programming language here]. Can I do that under the Swish-e License?
Why yes, you can! See FAQ #1.
Why did you switch from the LGPL? You've ruined [insert name of your favorite project here]!!

If you've got a project that depends on Swish-e and the LGPL, then you're probably familiar with the Swish-e source code. And therefore, you're probably also familiar with the fact that Swish-e is a smorgasbord of LGPL, GPL, BSD, MIT, public domain and other licenses.

The original "purity" of the LGPL status of Swish-e has long been in debate and as a consequence, Swish-e's licensure has been in limbo for years. That limbo worked for a while (hey, we're all friendly here right?), but in response to a specific request for the status of the Swish-e license, a thorough review was made of the source code. The result was the decision to officially declare ourselves a GPL'd project, but with the special exception for linking against libswish-e (see FAQ #1).

If the new Swish-e License still boggles you and ruins your day, feel free to contact the discussion list. We can probably sort something out.

What version(s) of Swish-e does this license apply to?
The Swish-e License is applicable to the 2.4.x release branch of Swish-e.
I'm confused. Are you saying that "we are GPL, but unlike normal GPL, we don't force you into GPL for using the code"?
No. We're saying "we can't force you into GPL for linking against the libswish-e library." That's just a little slice of the Swish-e pie. If you wanted to make a derivative work of the Swish-e code (like a Super-Swish), you can not release it without the GPL. (You could if Swish-e were still under the LGPL. But it's not.)
You mean I can use Swish-e in my project without obligation?

Well, not exactly. You have to provide source code for the actual version you use (you may point to swish-e.org if you use an unmodified version of the software and state the version).

In addition to that legal requirement, there are some strong recommendations that aren't legally required. You should make it clear to your users that you are using Swish-e in your product by listing Swish-e in your documentation and, if you have a web site, with an easy to find link on your web site. (Consider using the Swish-e logo). You must feel guilt if you add features or bug fixes to the software and do not inform other users of swish-e via the Swish-e discussion list, and you should think about buying the developers a beer. Or two. Or until they say 'stop'.