APPENDIX
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APPENDIX
Copyright (C) 1991, 1999 Free Software Foundation, Inc. 51
Franklin Street, 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 first released version of the Lesser GPL. It also
counts as the successor of the GNU Library Public License, ver-
sion 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 careful-
ly 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 soft-
ware (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
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are informed that you can do these things.
To protect your rights, we need to make restrictions that forbid
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For example, if you distribute copies of the library, whether gratis
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know their rights.
We protect your rights with a two-step method: (1) we copyright
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To protect each distributor, we want to make it very clear that
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Most GNU software, including some libraries, is covered by the
ordinary GNU General Public License. This license, the GNU
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mit linking those libraries into non-free programs.
When a program is linked with a library, whether statically or
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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 devel-
opers 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 pro-
vides 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.
GNU LESSER GENERAL PUBLIC LICENSE
Version 2.1, February 1999
