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 Pub-
lic 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 combina-
tion of the two is legally speaking a combined
work, a derivative of the original library. The ordi-
nary 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 soft-
ware 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 soft-
ware. 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 sys-
tem.
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, dis-
tribution and modification follow. Pay close atten-
tion 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.
Annexe
165