License Agreements
70
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
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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 making changes to the library and
recompiling it. And you must show them these terms so 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
modi
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ed 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
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Most GNU software, including some libraries, is covered by the
ordinary GNU General Public License. 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 programs.
When a program is linked with a library, whether statically
or using a shared library, the combination of the two is legally
speaking a combined work, a derivative of the original library. The
ordinary General Public License therefore permits such linking
only if the entire combination fits its criteria of freedom. The
Lesser General Public License permits more lax criteria for linking
other code with the library.
We call this license the "Lesser" General Public License
because it does Less to protect the user's freedom than the
ordinary General Public License. It also provides other free
software developers Less of an advantage over competing non-
free programs. These disadvantages are the reason we use the
ordinary General Public License for many libraries. However,
the Lesser license provides advantages in certain special
circumstances.
For example, on rare occasions, there may be a special need to
encourage the widest possible use of a certain library, so that it
becomes a de-facto standard. To achieve this, non-free programs
must be allowed to use the library. A more frequent case is that a
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In this case, there is little to gain by limiting the free library to free
software only, so we use the Lesser General Public License.
In other cases, permission to use a particular library in non-
free programs enables a greater number of people to use a large
body of free software. For example, permission to use the GNU
C Library in non-free programs enables many more people to use
the whole GNU operating system, as well as its variant, the GNU/
Linux operating system.
Although the Lesser General Public License is Less protective of
the users' freedom, it does ensure that the user of a program that
is linked with the Library has the freedom and the wherewithal to
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The precise terms and conditions for copying, distribution and
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The former contains code derived from the library, whereas the
latter must be combined with the library in order to run.
GNU LESSER GENERAL PUBLIC LICENSE
TERMS AND CONDITIONS FOR COPYING,
DISTRIBUTION AND MODIFICATION
0. This License Agreement applies to any software library or
other program which contains a notice placed by the copyright
holder or other authorized party saying it may be distributed under
the terms of this Lesser General Public License (also called "this
License"). Each licensee is addressed as "you".
A "library" means a collection of software functions and/or data
prepared so as to be conveniently linked with application programs
(which use some of those functions and data) to form executables.
The "Library", below, refers to any such software library or work
which has been distributed under these terms. A "work based on
the Library" means either the Library or any derivative work under
copyright law: that is to say, a work containing the Library or a
portion of it, either verbatim or with
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and/or translated
GNU LESSER GENERAL PUBLIC LICENSE Version 2.1, February 1999
Copyright © 1991, 1999 Free Software Foundation, Inc. 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
Everyone is permitted to copy and distribute verbatim copies of this license document, but changing it is not allowed.
[This is the
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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.]
End User License Agreement for Operating System Software
