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E x h i b i t B
GNU LESSER GENERAL PUBLIC LICENSE Version 2.1, February 1999
Copyright © 1991, 1999 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.
[ This is the first released version of the Lesser GPL. It also counts as the successor of
the GNU Library Public License, version 2, hence the version number 2.1.]
Preamble
The licenses for most software are designed to take away your freedom to share and
change it. By contrast, the GNU General Public Licenses are intended to guarantee your
freedom to share and change free software – to make sure the software is free for all its
users.
This license, the Lesser General Public License, applies to some specially designated
software packages – typically libraries – of the Free Software Foundation and other authors
who decide to use it. You can use it too, but we suggest you first think carefully about
whether this license or the ordinary General Public License is the better strategy to use in
any particular case, based on the explanations below.
When we speak of free software, we are referring to freedom of use, 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 and use pieces of it in
new free programs; and that you are informed that you can do these things.
To protect your rights, we need to make restrictions that forbid distributors to deny you
these rights or to ask you to surrender these rights. These restrictions translate to certain
responsibilities for you if you distribute copies of the library or if you modify it.
For example, if you distribute copies of the library, whether gratis or for a fee, you must
give the recipients all the rights that we gave you. You must make sure that they, too,
receive or can get the source code. If you link other code with the library, you must provide
complete object files to the recipients, so that they can relink them with the library after
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they know their rights.
We protect your rights with a two-step method: (1) we copyright the library, and (2) we
offer you this license, which gives you legal permission to copy, distribute and/or modify
the library.
To protect each distributor, we want to make it very clear that there is no warranty for the
free library. Also, if the library is modified by someone else and passed on, the recipients
should know that what they have is not the original version, so that the original author's
reputation will not be affected by problems that might be introduced by others.
Finally, software patents pose a constant threat to the existence of any free program. We
wish to make sure that a company cannot effectively restrict the users of a free program
by obtaining a restrictive license from a patent holder. Therefore, we insist that any patent
license obtained for a version of the library must be consistent with the full freedom of use
specified in this license.
Most GNU software, including some libraries, is covered by the ordinary GNU General
PublicLicense. This license, the GNU Lesser General Public License, applies to certain
designated libraries, and is quite different from the ordinary General Public License. We
use this license for certain libraries in order to permit linking those libraries into non-free
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