GNU LESSER GENERAL PUBLIC LICENSE
Version 2.1, February 1999
Copyright (C) 1991, 1999 Free Software Foundation, Inc.
59
Temple Place, Suite 330, Boston, MA 02111-1307 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.
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.
The "Library", below, refers to any such software library or
work which has been distributed under these terms. A "work based on
the Library" means either the Library or any derivative work under
copyright law: that is to say, a work containing the Library or a
portion of it, either verbatim or with modifications and/or
translated straightforwardly into another language. (Hereinafter,
translation is included without limitation in the term
"modification".)
"Source code" for a work means the preferred form of the work
for making modifications to it. For a library, complete source code
means all the source code for all modules it contains, plus any
associated interface definition files, plus the scripts used to
control compilation and installation of the library.
Activities other than copying, distribution and modification
are not covered by this License; they are outside its scope. The
act of running a program using the Library is not restricted, and
output from such a program is covered only if its contents
constitute a work based on the Library (independent of the use of
the Library in a tool for writing it). Whether that is true depends
on what the Library does and what the program that uses the Library
does.
1. You may copy and distribute verbatim copies of
the Library's complete source code as you receive it, in any
medium, provided that you conspicuously and appropriately publish
on each copy an appropriate copyright notice and disclaimer of
warranty; keep intact all the notices that refer to this License
and to the absence of any warranty; and distribute a copy of this
License along with the Library.
You may charge a fee for the physical act of transferring a
copy, and you may at your option offer warranty protection in
exchange for a fee.
2. You may modify your copy or copies of the
Library or any portion of it, thus forming a work based on the
Library, and copy and distribute such modifications or work under
the terms of Section 1 above, provided that you also meet all of
these conditions:
- a) The modified work must itself be a
software library.
- b) You must cause the files modified to
carry prominent notices stating that you changed the files and the
date of any change.
- c) You must cause the whole of the work
to be licensed at no charge to all third parties under the terms
of this License.
- d) If a facility in the modified Library
refers to a function or a table of data to be supplied by an
application program that uses the facility, other than as an
argument passed when the facility is invoked, then you must make a
good faith effort to ensure that, in the event an application does
not supply such function or table, the facility still operates,
and performs whatever part of its purpose remains meaningful.
(For example, a function in a library to compute square
roots has a purpose that is entirely well-defined independent of
the application. Therefore, Subsection 2d requires that any
application-supplied function or table used by this function must
be optional: if the application does not supply it, the square
root function must still compute square roots.)
These requirements apply to the modified work as a whole.
If identifiable sections of that work are not derived from the
Library, and can be reasonably considered independent and
separate works in themselves, then this License, and its terms,
do not apply to those sections when you distribute them as
separate works. But when you distribute the same sections as part
of a whole which is a work based on the Library, the distribution
of the whole must be on the terms of this License, whose
permissions for other licensees extend to the entire whole, and
thus to each and every part regardless of who wrote it.
Thus, it is not the intent of this section to claim rights
or contest your rights to work written entirely by you; rather,
the intent is to exercise the right to control the distribution
of derivative or collective works based on the Library.
In addition, mere aggregation of another work not based on
the Library with the Library (or with a work based on the
Library) on a volume of a storage or distribution medium does not
bring the other work under the scope of this License.
3. You may opt to apply the terms of the ordinary
GNU General Public License instead of this License to a given copy
of the Library. To do this, you must alter all the notices that
refer to this License, so that they refer to the ordinary GNU
General Public License, version 2, instead of to this License. (If
a newer version than version 2 of the ordinary GNU General Public
License has appeared, then you can specify that version instead if
you wish.) Do not make any other change in these notices.
Once this change is made in a given copy, it is irreversible
for that copy, so the ordinary GNU General Public License applies
to all subsequent copies and derivative works made from that copy.
This option is useful when you wish to copy part of the code
of the Library into a program that is not a library.
4. You may copy and distribute the Library (or a
portion or derivative of it, under Section 2) in object code or
executable form under the terms of Sections 1 and 2 above provided
that you accompany it with the complete corresponding
machine-readable source code, which must be distributed under the
terms of Sections 1 and 2 above on a medium customarily used for
software interchange.
If distribution of object code is made by offering access to
copy from a designated place, then offering equivalent access to
copy the source code from the same place satisfies the requirement
to distribute the source code, even though third parties are not
compelled to copy the source along with the object code.
5. A program that contains no derivative of any
portion of the Library, but is designed to work with the Library by
being compiled or linked with it, is called a "work that uses the
Library". Such a work, in isolation, is not a derivative work of
the Library, and therefore falls outside the scope of this License.
However, linking a "work that uses the Library" with the
Library creates an executable that is a derivative of the Library
(because it contains portions of the Library), rather than a "work
that uses the library". The executable is therefore covered by this
License. Section 6 states terms for distribution of such
executables.
When a "work that uses the Library" uses material from a
header file that is part of the Library, the object code for the
work may be a derivative work of the Library even though the source
code is not. Whether this is true is especially significant if the
work can be linked without the Library, or if the work is itself a
library. The threshold for this to be true is not precisely defined
by law.
If such an object file uses only numerical parameters, data
structure layouts and accessors, and small macros and small inline
functions (ten lines or less in length), then the use of the object
file is unrestricted, regardless of whether it is legally a
derivative work. (Executables containing this object code plus
portions of the Library will still fall under Section 6.)
Otherwise, if the work is a derivative of the Library, you
may distribute the object code for the work under the terms of
Section 6. Any executables containing that work also fall under
Section 6, whether or not they are linked directly with the Library
itself.
6. As an exception to the Sections above, you may
also combine or link a "work that uses the Library" with the
Library to produce a work containing portions of the Library, and
distribute that work under terms of your choice, provided that the
terms permit modification of the work for the customer's own use
and reverse engineering for debugging such modifications.
You must give prominent notice with each copy of the work
that the Library is used in it and that the Library and its use are
covered by this License. You must supply a copy of this License. If
the work during execution displays copyright notices, you must
include the copyright notice for the Library among them, as well as
a reference directing the user to the copy of this License. Also,
you must do one of these things:
- a) Accompany the work with the complete
corresponding machine-readable source code for the Library
including whatever changes were used in the work (which must be
distributed under Sections 1 and 2 above); and, if the work is an
executable linked with the Library, with the complete
machine-readable "work that uses the Library", as object code
and/or source code, so that the user can modify the Library and
then relink to produce a modified executable containing the
modified Library. (It is understood that the user who changes the
contents of definitions files in the Library will not necessarily
be able to recompile the application to use the modified
definitions.)
- b) Use a suitable shared library
mechanism for linking with the Library. A suitable mechanism is
one that (1) uses at run time a copy of the library already
present on the user's computer system, rather than copying library
functions into the executable, and (2) will operate properly with
a modified version of the library, if the user installs one, as
long as the modified version is interface-compatible with the
version that the work was made with.
- c) Accompany the work with a written
offer, valid for at least three years, to give the same user the
materials specified in Subsection 6a, above, for a charge no more
than the cost of performing this distribution.
- d) If distribution of the work is made by
offering access to copy from a designated place, offer equivalent
access to copy the above specified materials from the same place.
- e) Verify that the user has already
received a copy of these materials or that you have already sent
this user a copy.
For an executable, the required form of the "work that uses
the Library" must include any data and utility programs needed for
reproducing the executable from it. However, as a special
exception, the materials to be distributed need not include
anything that is normally distributed (in either source or binary
form) with the major components (compiler, kernel, and so on) of
the operating system on which the executable runs, unless that
component itself accompanies the executable.
It may happen that this requirement contradicts the license
restrictions of other proprietary libraries that do not normally
accompany the operating system. Such a contradiction means you
cannot use both them and the Library together in an executable that
you distribute.
7. You may place library facilities that are a
work based on the Library side-by-side in a single library together
with other library facilities not covered by this License, and
distribute such a combined library, provided that the separate
distribution of the work based on the Library and of the other
library facilities is otherwise permitted, and provided that you do
these two things:
- a) Accompany the combined library with a
copy of the same work based on the Library, uncombined with any
other library facilities. This must be distributed under the terms
of the Sections above.
- b) Give prominent notice with the
combined library of the fact that part of it is a work based on
the Library, and explaining where to find the accompanying
uncombined form of the same work.
8. You may not copy, modify, sublicense, link
with, or distribute the Library except as expressly provided under
this License. Any attempt otherwise to copy, modify, sublicense,
link with, or distribute the Library is void, and will
automatically terminate your rights under this License. However,
parties who have received copies, or rights, from you under this
License will not have their licenses terminated so long as such
parties remain in full compliance.
9. You are not required to accept this License,
since you have not signed it. However, nothing else grants you
permission to modify or distribute the Library or its derivative
works. These actions are prohibited by law if you do not accept
this License. Therefore, by modifying or distributing the Library
(or any work based on the Library), you indicate your acceptance of
this License to do so, and all its terms and conditions for
copying, distributing or modifying the Library or works based on
it.
10. Each time you redistribute the Library (or any
work based on the Library), the recipient automatically receives a
license from the original licensor to copy, distribute, link with
or modify the Library subject to these terms and conditions. You
may not impose any further restrictions on the recipients' exercise
of the rights granted herein. You are not responsible for enforcing
compliance by third parties with this License.
11. If, as a consequence of a court judgment or
allegation of patent infringement or for any other reason (not
limited to patent issues), conditions are imposed on you (whether
by court order, agreement or otherwise) that contradict the
conditions of this License, they do not excuse you from the
conditions of this License. If you cannot distribute so as to
satisfy simultaneously your obligations under this License and any
other pertinent obligations, then as a consequence you may not
distribute the Library at all. For example, if a patent license
would not permit royalty-free redistribution of the Library by all
those who receive copies directly or indirectly through you, then
the only way you could satisfy both it and this License would be to
refrain entirely from distribution of the Library.
If any portion of this section is held invalid or
unenforceable under any particular circumstance, the balance of the
section is intended to apply, and the section as a whole is
intended to apply in other circumstances.
It is not the purpose of this section to induce you to
infringe any patents or other property right claims or to contest
validity of any such claims; this section has the sole purpose of
protecting the integrity of the free software distribution system
which is implemented by public license practices. Many people have
made generous contributions to the wide range of software
distributed through that system in reliance on consistent
application of that system; it is up to the author/donor to decide
if he or she is willing to distribute software through any other
system and a licensee cannot impose that choice.
This section is intended to make thoroughly clear what is
believed to be a consequence of the rest of this License.
12. If the distribution and/or use of the Library
is restricted in certain countries either by patents or by
copyrighted interfaces, the original copyright holder who places
the Library under this License may add an explicit geographical
distribution limitation excluding those countries, so that
distribution is permitted only in or among countries not thus
excluded. In such case, this License incorporates the limitation as
if written in the body of this License.
13. The Free Software Foundation may publish
revised and/or new versions of the Lesser General Public License
from time to time. Such new versions will be similar in spirit to
the present version, but may differ in detail to address new
problems or concerns.
Each version is given a distinguishing version number. If the
Library specifies a version number of this License which applies to
it and "any later version", you have the option of following the
terms and conditions either of that version or of any later version
published by the Free Software Foundation. If the Library does not
specify a license version number, you may choose any version ever
published by the Free Software Foundation.
14. If you wish to incorporate parts of the
Library into other free programs whose distribution conditions are
incompatible with these, write to the author to ask for permission.
For software which is copyrighted by the Free Software Foundation,
write to the Free Software Foundation; we sometimes make exceptions
for this. Our decision will be guided by the two goals of
preserving the free status of all derivatives of our free software
and of promoting the sharing and reuse of software generally.
NO WARRANTY
15. BECAUSE THE LIBRARY IS LICENSED FREE OF
CHARGE, THERE IS NO WARRANTY FOR THE LIBRARY, TO THE EXTENT
PERMITTED BY APPLICABLE LAW. EXCEPT WHEN OTHERWISE STATED IN
WRITING THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES PROVIDE THE
LIBRARY "AS IS" WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED OR
IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE ENTIRE
RISK AS TO THE QUALITY AND PERFORMANCE OF THE LIBRARY IS WITH YOU.
SHOULD THE LIBRARY PROVE DEFECTIVE, YOU ASSUME THE COST OF ALL
NECESSARY SERVICING, REPAIR OR CORRECTION.
16. IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW
OR AGREED TO IN WRITING WILL ANY COPYRIGHT HOLDER, OR ANY OTHER
PARTY WHO MAY MODIFY AND/OR REDISTRIBUTE THE LIBRARY AS PERMITTED
ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY GENERAL,
SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE USE
OR INABILITY TO USE THE LIBRARY (INCLUDING BUT NOT LIMITED TO LOSS
OF DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY
YOU OR THIRD PARTIES OR A FAILURE OF THE LIBRARY TO OPERATE WITH
ANY OTHER SOFTWARE), EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN
ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.
END OF TERMS AND CONDITIONS
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 safest to attach them to the start of each source
file to most effectively convey the exclusion of warranty; and each
file should have at least the "copyright" line and a pointer to
where the full notice is found.
one line to give the library's name and an idea of what
it does.
Copyright (C)
year
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
License along with this library; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
USA
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 school, if any, to sign a "copyright
disclaimer" for the library, if necessary. Here is a sample; alter
the names:
Yoyodyne, Inc., hereby disclaims all copyright interest in
the library `Frob' (a library for tweaking knobs) written
by James Random Hacker.
signature of Ty Coon
, 1 April 1990
Ty Coon, President of Vice
That's all there is to it! |
