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The hypothetical commands ‘show w’ and ‘show c’ should show
the appropriate parts of the General Public License. Of course,
the commands you use may be called something other than
‘show w’ and ‘show c’; they could even be mouse-clicks or
menu items--whatever suits your program.
You should also get your employer (if you work as a
programmer) or your school, if any, to sign a “copyright
disclaimer” for the program, if necessary. Here is a sample; alter
the names:
Yoyodyne, Inc., hereby disclaims all copyright interest in the
program ‘Gnomovision’ (which makes passes at compilers)
written by James Hacker.
<signature of Ty Coon>, 1 April 1989
Ty Coon, President of Vice
This General Public License does not permit incorporating your
program into proprietary programs. If your program is a
subroutine library, you may consider it more useful to permit
linking proprietary applications with the library. If this is what
you want to do, use the GNU Lesser General Public License
instead of this License.
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 freedom of
use, not price. Our General Public Licenses are designed to make
sure that you have the freedom to distribute copies of free
software (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 software and use pieces of it in new free programs;
and that you are informed that you can do these things.
To protect your rights, we need to make restrictions that forbid
distributors to deny you these rights or to ask you to surrender
these rights. These restrictions translate to certain
responsibilities for you if you distribute copies of the library or
if you modify it.
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 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 non-free 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.
GNU GENERAL PUBLIC LICENSE 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 functions and data) to form
executables.
,
continued