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Notice Concerning Software Governed by the GNU GPL/LGPL
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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 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 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 defacto standard. To achieve this, non-free programs must be allowed to use the library. A more frequent
case is that a free library does the same job as widely used non-free libraries. 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 run that program using a modified version
of the Library.
The precise terms and conditions for copying, distribution and modification follow. Pay close attention to the difference
between a “work based on the library” and a “work that uses the library”. The former contains code derived from the library,
whereas the latter must be combined with the library in order to run.
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”.
