conditions either of that version or of any later version
published by the Free Software Foundation. If the
Program does not specify a version number of this
License, you may choose any version ever published
by the Free Software Foundation.
NO WARRANTY
________________________________
GNU LESSER GENERAL PUBLIC LICENSE
Version 2.1, February 1999
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, version 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
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
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To protect your rights, we need to make restrictions
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And you must show them these terms so they know
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We protect your rights with a two-step method: (1) we
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To protect each distributor, we want to make it very
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Also, if the library is modified by someone else and
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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
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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
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When a program is linked with a library, whether
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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
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