LICENSE
TERMS AND CONDITIONS FOR COPYING,
DISTRIBUTION AND MODIFICA TION
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 L esser
General P ublic 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 link ed
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 modications and/
or translated straightforwardly into another language.
(Hereinafter , translation is included without limitation
in the term “modication ”.)
“Source code” for a work means the preferred form of
the work for making modications to it. F or a library ,
complete source code means all the source code for
all modules it contains, plus any associated interface
denition les, plus the scripts used to control
compilation and installation of the library .
Activities other than copying, distribution and
modication 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. Y ou 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; k eep
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 .
Y ou 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. Y ou 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 modications
or work under the terms of Section 1 above, provided
that you also meet all of these conditions:
a) The modied work must itself be a software library .
b) Y ou must cause the les modied to carry prominent
notices stating that you changed the les and the
date of any change.
c) Y ou must cause the whole of the work to be licensed
at no charge to all third parties under the terms of
this License.
d) I f a fac il it y in th e mod i ed Lib rar y re fe rs to a func ti on
or a t abl e of d at a t o b e s u ppl ie d b y an a pp li cat io n
pr og ram tha t us es the fac ili ty , oth er tha n as an
ar gu men t pas se d when t h e faci li ty i s inv ok ed , the n
yo u mus t ma k e a g oo d fa it h e ff or t to en su re t ha t,
in th e ev en t an ap pl ic ati on do es no t s upp ly su ch fu nct io n
or t ab le , th e f aci li ty sti ll op era te s, and pe rfo rm s w hat ev er
pa rt of i ts p ur pos e re ma in s m ea ni ng fu l.
(F or example, a function in a library to compute
square roots has a purpose that is entirely well-
dened 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 modied work
as a whole. If identiable 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. Y ou may opt to apply the terms of the ordinary GNU
General Public License instead of this License to a
given copy of the Library . T o 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 P ublic 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
P ublic 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. Y ou 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 satises 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 link ed 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 le 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 signicant if the work
can be link ed without the Library , or if the work is
itself a library . The threshold for this to be true is not
precisely dened by law .
If such an object le 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 le 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 modication
of the work for the customer’s own use and reverse
engineering for debugging such modications.
Y ou 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. Y ou
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 modied executable containing the modied
Library . (It is understood that the user who changes
the contents of denitions les in the Library will not
necessarily be able to recompile the application to
use the modied denitions.)
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 modied version of
the library , if the user installs one, as long as the
modied 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 specied 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 specied materials from
the same place.
e) V erify that the user has already received a copy of
these materials or that you have already sent this
user a copy .
F or 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. Y ou 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 nd the accompanying
uncombined form of the same work.
8. Y ou 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.