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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 nonfree
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 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". 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
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distributed under these terms. A "work based on the Library" means either the Library or any derivative work under
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translated straightforwardly into another language. (Hereinafter, translation is included without limitation in the term
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library, complete source code means all the source code for all modules it contains, plus any associated interface
definition files, plus the scripts used to control compilation and installation of the library. Activities other than copying,
distribution and modification are not covered by this License; they are outside its scope. The act of running a program
using the Library is not restricted, and output from such a program is covered only if its contents constitute a work based
on the Library (independent of the use of the Library in a tool for writing it). Whether that is true depends on what the
Library does and what the program that uses the Library does.
1. You may copy and distribute verbatim copies of the Library's complete 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
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b) You must cause the files modified to carry prominent notices stating that you changed the files and the date of any
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c) You must cause the whole of the work to be licensed at no charge to all third parties under the terms of this License.
d) If a facility in the modified Library refers to a function or a table of data to be supplied by an application program that
uses the facility, other than as an argument passed when the facility is invoked, then you must make a good faith effort to
ensure that, in the event an application does not supply such function or table, the facility still operates, and performs
whatever part of its purpose remains meaningful. (For example, a function in a library to compute square roots has a
purpose that is entirely well-defined independent of the application. Therefore, Subsection 2d requires that any
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