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[bacula/docs] / docs / manual / lesser.tex

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\section*{GNU Lesser General Public License}
\label{LesserChapter}
\index[general]{GNU Lesser General Public License }
\index[general]{License!GNU Lesser General Public }

\elink{image of a Philosophical
GNU}{http://www.gnu.org/graphics/philosophicalgnu.html} [  
\elink{English}{http://www.gnu.org/copyleft/lesser.html} | 
\elink{Japanese}{http://www.gnu.org/copyleft/lesser.ja.html} ] 

\begin{itemize}
\item 
   \elink{Why you shouldn't use the Lesser GPL for your next
   library}{http://www.gnu.org/philosophy/why-not-lgpl.html}  
\item 
   \elink{What to do if you see a possible LGPL
   violation}{http://www.gnu.org/copyleft/gpl-violation.html}  
\item 
   \elink{Translations of the
   LGPL}{http://www.gnu.org/copyleft/copyleft.html\#translationsLGPL}  
\item The GNU Lesser General Public License as a  
   \elink{text file}{http://www.gnu.org/copyleft/lesser.txt}  
\item The GNU Lesser General Public License as a  
   \elink{Texinfo}{http://www.gnu.org/copyleft/lesser.texi} file 
   \end{itemize}


This GNU Lesser General Public License counts as the successor of the GNU
Library General Public License. For an explanation of why this change was
necessary, read the 
\elink{Why you shouldn't use the Lesser GPL for your next
library}{http://www.gnu.org/philosophy/why-not-lgpl.html} article. 

\section{Table of Contents}
\index[general]{Table of Contents }
\index[general]{Contents!Table of }

\begin{itemize}
\item 
   \label{TOC12}
   \ilink{GNU LESSER GENERAL PUBLIC LICENSE}{SEC12} 

\begin{itemize}
\item 
   \label{TOC23}
   \ilink{Preamble}{SEC23} 
\item 
   \label{TOC34}
   \ilink{TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND
MODIFICATION}{SEC34} 
\item 
   \label{TOC45}
   \ilink{How to Apply These Terms to Your New Libraries}{SEC45} 
\end{itemize}

\end{itemize}


\section{
\ilink{GNU LESSER GENERAL PUBLIC LICENSE}{TOC12}}
\label{SEC12}
\index[general]{LICENSE!GNU LESSER GENERAL PUBLIC }
\index[general]{GNU LESSER GENERAL PUBLIC LICENSE }

Version 2.1, February 1999 

\footnotesize
\begin{verbatim}
Copyright (C) 1991, 1999 Free Software Foundation, Inc.
51 Franklin St, 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.]
\end{verbatim}
\normalsize

\section{
\ilink{Preamble}{TOC23}}
\label{SEC23}
\index[general]{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\verb:--: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\verb:--:typically libraries\verb:--: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
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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
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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,
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To protect each distributor, we want to make it very clear that there is no
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Finally, software patents pose a constant threat to the existence of any free
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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. 

\section{
\ilink{TERMS AND CONDITIONS}{TOC34}}
\label{SEC34}
\index[general]{CONDITIONS!TERMS AND }
\index[general]{TERMS AND CONDITIONS }

TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION 

{\bf 0.} This License Agreement applies to any software library or other
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END OF TERMS AND CONDITIONS 

\section{
\ilink{How to Apply These Terms to Your New Libraries}{TOC45}}
\label{SEC45}
\index[general]{Libraries!How to Apply These Terms to Your New }
\index[general]{How to Apply These Terms to Your New Libraries }


If you develop a new library, and you want it to be of the greatest possible
use to the public, we recommend making it free software that everyone can
redistribute and change. You can do so by permitting redistribution under
these terms (or, alternatively, under the terms of the ordinary General Public
License). 

To apply these terms, attach the following notices to the library. It is
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"copyright" line and a pointer to where the full notice is found. 

\footnotesize
\begin{verbatim}
{\it one line to give the library's name and an idea of what it does.}
Copyright (C) {\it year}  {\it name of author}
This library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
This library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
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Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301
USA
\end{verbatim}
\normalsize

Also add information on how to contact you by electronic and paper mail. 

You should also get your employer (if you work as a programmer) or your
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\footnotesize
\begin{verbatim}
Yoyodyne, Inc., hereby disclaims all copyright interest in
the library "Frob" (a library for tweaking knobs) written
by James Random Hacker.
{\it signature of Ty Coon}, 1 April 1990
Ty Coon, President of Vice
\end{verbatim}
\normalsize

That's all there is to it! 
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Updated: 27 Nov 2000 paulv