<s>
A	O
GPL	B-Application
linking	I-Application
exception	I-Application
modifies	O
the	O
GNU	B-License
General	I-License
Public	I-License
License	I-License
(	O
GPL	B-License
)	O
in	O
a	O
way	O
that	O
enables	O
software	O
projects	O
which	O
provide	O
library	B-Library
code	O
to	O
be	O
"	O
linked	B-Application
to	I-Application
"	O
the	O
programs	O
that	O
use	O
them	O
,	O
without	O
applying	O
the	O
full	O
terms	O
of	O
the	O
GPL	B-License
to	O
the	O
using	O
program	O
.	O
</s>
<s>
Linking	B-Application
is	O
the	O
technical	O
process	O
of	O
connecting	O
code	O
in	O
a	O
library	B-Library
to	O
the	O
using	O
code	O
,	O
to	O
produce	O
a	O
single	O
executable	B-Application
file	I-Application
.	O
</s>
<s>
It	O
is	O
performed	O
either	O
at	O
compile	B-Application
time	I-Application
or	O
run-time	B-Library
in	O
order	O
to	O
produce	O
functional	O
machine-readable	O
code	O
.	O
</s>
<s>
The	O
Free	O
Software	O
Foundation	O
states	O
that	O
,	O
without	O
applying	O
the	O
linking	B-Application
exception	O
,	O
a	O
program	O
linked	B-Application
to	I-Application
GPL	B-License
library	B-Library
code	O
may	O
only	O
be	O
distributed	O
under	O
a	O
GPL-compatible	O
license	O
.	O
</s>
<s>
This	O
has	O
not	O
been	O
explicitly	O
tested	O
in	O
court	O
,	O
but	O
linking	B-Application
violations	O
have	O
resulted	O
in	O
settlement	O
.	O
</s>
<s>
The	O
license	O
of	O
the	O
GNU	B-Language
Classpath	I-Language
project	O
explicitly	O
includes	O
a	O
statement	O
to	O
that	O
effect	O
.	O
</s>
<s>
Many	O
free	O
software	B-Library
libraries	I-Library
which	O
are	O
distributed	O
under	O
the	O
GPL	B-License
use	O
an	O
equivalent	O
exception	O
,	O
although	O
the	O
wording	O
of	O
the	O
exception	O
varies	O
.	O
</s>
<s>
Notable	O
projects	O
include	O
ERIKA	B-Operating_System
Enterprise	I-Operating_System
,	O
GNU	B-Application
Guile	I-Application
,	O
the	O
run-time	B-Library
libraries	O
of	O
GNAT	B-Language
,	O
GNU	B-Language
Classpath	I-Language
and	O
the	O
GCC	B-Application
Runtime	B-Library
Library	B-Library
Exception	O
.	O
</s>
<s>
Compiler	O
runtime	B-Library
libraries	O
also	O
often	O
use	O
this	O
license	O
modification	O
or	O
an	O
equivalent	O
one	O
,	O
e.g.	O
</s>
<s>
the	O
libgcc	B-Application
library	B-Library
in	O
the	O
GNU	B-Application
Compiler	I-Application
Collection	I-Application
,	O
as	O
well	O
as	O
all	O
libraries	O
of	O
the	O
Free	B-Operating_System
Pascal	I-Operating_System
project	O
.	O
</s>
<s>
In	O
2007	O
,	O
Sun	O
Microsystems	O
released	O
most	O
of	O
the	O
source	O
code	O
to	O
the	O
class	B-Application
libraries	I-Application
for	O
the	O
Java	B-Language
SE	I-Language
and	O
Java	B-Language
EE	I-Language
projects	O
under	O
version	O
2	O
of	O
the	O
GPL	B-License
license	I-License
plus	O
the	O
Classpath	O
linking	B-Application
exception	O
,	O
and	O
used	O
the	O
same	O
license	O
as	O
one	O
possible	O
license	O
for	O
their	O
enterprise	O
server	O
GlassFish	B-Language
and	O
for	O
their	O
NetBeans	B-Application
Java	O
IDE	B-Application
.	O
</s>
<s>
Version	O
3	O
of	O
the	O
GNU	B-Application
Lesser	I-Application
General	I-Application
Public	I-Application
License	I-Application
(	O
LGPL	B-Application
)	O
is	O
likewise	O
constructed	O
as	O
an	O
exception	O
to	O
the	O
GPL	B-License
.	O
</s>
<s>
The	O
GNU	B-Language
Classpath	I-Language
project	O
provides	O
an	O
example	O
of	O
the	O
use	O
of	O
such	O
a	O
GPL	B-Application
linking	I-Application
exception	I-Application
.	O
</s>
<s>
The	O
GNU	B-Language
Classpath	I-Language
library	B-Library
uses	O
the	O
following	O
license	O
:	O
</s>
<s>
When	O
GNU	B-Language
Classpath	I-Language
is	O
used	O
unmodified	O
as	O
the	O
core	O
class	B-Application
library	I-Application
for	O
a	O
virtual	O
machine	O
,	O
compiler	O
for	O
the	O
Java	O
language	O
,	O
or	O
for	O
a	O
program	O
written	O
in	O
the	O
Java	O
programming	O
language	O
it	O
does	O
not	O
affect	O
the	O
licensing	O
for	O
distributing	O
those	O
programs	O
directly	O
.	O
</s>
<s>
While	O
version	O
2.1	O
of	O
the	O
LGPL	B-Application
was	O
a	O
standalone	O
licence	O
,	O
the	O
current	O
LGPL	B-Application
version	O
3	O
is	O
based	O
on	O
a	O
reference	O
to	O
the	O
GPL	B-License
.	O
</s>
<s>
Compared	O
to	O
the	O
GNU	B-Language
Classpath	I-Language
license	O
above	O
,	O
the	O
LGPL	B-Application
formulates	O
more	O
requirements	O
to	O
the	O
linking	B-Application
exception	O
:	O
licensees	O
must	O
allow	O
modification	O
of	O
the	O
portions	O
of	O
the	O
library	B-Library
they	O
use	O
and	O
reverse	O
engineering	O
(	O
of	O
their	O
software	O
and	O
the	O
library	B-Library
)	O
for	O
debugging	O
such	O
modifications	O
.	O
</s>
