blic Licenses are designed to make sure that you have the freedom to distribute copies of free
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To protect your rights, we need to make restrictions that forbid distributors to deny you these
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We protect your rights with a two-step method: (1) we copyright the library, and (2) we offer you
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Most GNU software, including some libraries, is covered by the ordinary GNU General Public Li-
cense. This license, the GNU Lesser General Public License, applies to certain designated libraries,
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raries 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 combi-
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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 develo-
pers Less of an advantage over competing non-free programs. These disadvantages are the re-
ason 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 possib-
le use of a certain library, so that it becomes a de-facto standard. To achieve this, non-free pro-
grams 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 sys-
tem, 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 ensu-
re 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 at-
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