GNU GENERAL PUBLIC LICENSE
Version 2, June 1991
Copyrigh (C) 1989, 1991 Free Sof ware Founda ion, Inc.
51 Franklin S ree , Fif h Floor, Bos on, MA 02110-1301 USA
Everyone is permi ed o copy and dis ribu e verba im copies
of his license documen , bu changing i is no allowed.
Preamble
The licenses for mos sof ware are designed o ake away your
freedom o share and change i . By con ras , he GNU General Public
License is in ended o guaran ee your freedom o share and change free
sof ware-- o make sure he sof ware is free for all i s users. This
General Public License applies o mos of he Free Sof ware
Founda ion's sof ware and o any o her program whose au hors commi o
using i . (Some o her Free Sof ware Founda ion sof ware is covered by
he GNU Library General Public License ins ead.) You can apply i o
your programs, oo.
When we speak of free sof ware, we are referring o freedom, no
price. Our General Public Licenses are designed o make sure ha you
have he freedom o dis ribu e copies of free sof ware (and charge for
his service if you wish), ha you receive source code or can ge i
if you wan i , ha you can change he sof ware or use pieces of i
in new free programs; and ha you know you can do hese hings.
To pro ec your righ s, we need o make res ric ions ha forbid
anyone o deny you hese righ s or o ask you o surrender he righ s.
These res ric ions ransla e o cer ain responsibili ies for you if you
dis ribu e copies of he sof ware, or if you modify i .
For example, if you dis ribu e copies of such a program, whe her
gra is or for a fee, you mus give he recipien s all he righ s ha
you have. You mus make sure ha hey, oo, receive or can ge he
source code. And you mus show hem hese erms so hey know heir
righ s.
We pro ec your righ s wi h wo s eps: (1) copyrigh he sof ware, and
(2) offer you his license which gives you legal permission o copy,
dis ribu e and/or modify he sof ware.
Also, for each au hor's pro ec ion and ours, we wan o make cer ain
ha everyone unders ands ha here is no warran y for his free
sof ware. If he sof ware is modified by someone else and passed on, we
wan i s recipien s o know ha wha hey have is no he original, so
ha any problems in roduced by o hers will no reflec on he original
au hors' repu a ions.
Finally, any free program is hrea ened cons an ly by sof ware
pa en s. We wish o avoid he danger ha redis ribu ors of a free
program will individually ob ain pa en licenses, in effec making he
program proprie ary. To preven his, we have made i clear ha any
pa en mus be licensed for everyone's free use or no licensed a all.
The precise erms and condi ions for copying, dis ribu ion and
modifica ion follow.
GNU GENERAL PUBLIC LICENSE
TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION
0. This License applies o any program or o her work which con ains
a no ice placed by he copyrigh holder saying i may be dis ribu ed
under he erms of his General Public License. The "Program", below,
refers o any such program or work, and a "work based on he Program"
means ei her he Program or any deriva ive work under copyrigh law:
ha is o say, a work con aining he Program or a por ion of i ,
ei her verba im or wi h modifica ions and/or ransla ed in o ano her
language. (Hereinaf er, ransla ion is included wi hou limi a ion in
he erm "modifica ion".) Each licensee is addressed as "you".
Ac ivi ies o her han copying, dis ribu ion and modifica ion are no
covered by his License; hey are ou side i s scope. The ac of
running he Program is no res ric ed, and he ou pu from he Program
is covered only if i s con en s cons i u e a work based on he
Program (independen of having been made by running he Program).
Whe her ha is rue depends on wha he Program does.
1. You may copy and dis ribu e verba im copies of he Program's
source code as you receive i , in any medium, provided ha you
conspicuously and appropria ely publish on each copy an appropria e
copyrigh no ice and disclaimer of warran y; keep in ac all he
no ices ha refer o his License and o he absence of any warran y;
and give any o her recipien s of he Program a copy of his License
along wi h he Program.
You may charge a fee for he physical ac of ransferring a copy, and
you may a your op ion offer warran y pro ec ion in exchange for a fee.
2. You may modify your copy or copies of he Program or any por ion
of i , hus forming a work based on he Program, and copy and
dis ribu e such modifica ions or work under he erms of Sec ion 1
above, provided ha you also mee all of hese condi ions:
a) You mus cause he modified files o carry prominen no ices
s a ing ha you changed he files and he da e of any change.
b) You mus cause any work ha you dis ribu e or publish, ha in
whole or in par con ains or is derived from he Program or any
par hereof, o be licensed as a whole a no charge o all hird
par ies under he erms of his License.
c) If he modified program normally reads commands in erac ively
when run, you mus cause i , when s ar ed running for such
in erac ive use in he mos ordinary way, o prin or display an
announcemen including an appropria e copyrigh no ice and a
no ice ha here is no warran y (or else, saying ha you provide
a warran y) and ha users may redis ribu e he program under
hese condi ions, and elling he user how o view a copy of his
License. (Excep ion: if he Program i self is in erac ive bu
does no normally prin such an announcemen , your work based on
he Program is no required o prin an announcemen .)
These requiremen s apply o he modified work as a whole. If
iden ifiable sec ions of ha work are no derived from he Program,
and can be reasonably considered independen and separa e works in
hemselves, hen his License, and i s erms, do no apply o hose
sec ions when you dis ribu e hem as separa e works. Bu when you
dis ribu e he same sec ions as par of a whole which is a work based
on he Program, he dis ribu ion of he whole mus be on he erms of
his License, whose permissions for o her licensees ex end o he
en ire whole, and hus o each and every par regardless of who wro e i .
Thus, i is no he in en of his sec ion o claim righ s or con es
your righ s o work wri en en irely by you; ra her, he in en is o
exercise he righ o con rol he dis ribu ion of deriva ive or
collec ive works based on he Program.
In addi ion, mere aggrega ion of ano her work no based on he Program
wi h he Program (or wi h a work based on he Program) on a volume of
a s orage or dis ribu ion medium does no bring he o her work under
he scope of his License.
3. You may copy and dis ribu e he Program (or a work based on i ,
under Sec ion 2) in objec code or execu able form under he erms of
Sec ions 1 and 2 above provided ha you also do one of he following:
a) Accompany i wi h he comple e corresponding machine-readable
source code, which mus be dis ribu ed under he erms of Sec ions
1 and 2 above on a medium cus omarily used for sof ware in erchange; or,
b) Accompany i wi h a wri en offer, valid for a leas hree
years, o give any hird par y, for a charge no more han your
cos of physically performing source dis ribu ion, a comple e
machine-readable copy of he corresponding source code, o be
dis ribu ed under he erms of Sec ions 1 and 2 above on a medium
cus omarily used for sof ware in erchange; or,
c) Accompany i wi h he informa ion you received as o he offer
o dis ribu e corresponding source code. (This al erna ive is
allowed only for noncommercial dis ribu ion and only if you
received he program in objec code or execu able form wi h such
an offer, in accord wi h Subsec ion b above.)
The source code for a work means he preferred form of he work for
making modifica ions o i . For an execu able work, comple e source
code means all he source code for all modules i con ains, plus any
associa ed in erface defini ion files, plus he scrip s used o
con rol compila ion and ins alla ion of he execu able. However, as a
special excep ion, he source code dis ribu ed need no include
any hing ha is normally dis ribu ed (in ei her source or binary
form) wi h he major componen s (compiler, kernel, and so on) of he
opera ing sys em on which he execu able runs, unless ha componen
i self accompanies he execu able.
If dis ribu ion of execu able or objec code is made by offering
access o copy from a designa ed place, hen offering equivalen
access o copy he source code from he same place coun s as
dis ribu ion of he source code, even hough hird par ies are no
compelled o copy he source along wi h he objec code.
4. You may no copy, modify, sublicense, or dis ribu e he Program
excep as expressly provided under his License. Any a emp
o herwise o copy, modify, sublicense or dis ribu e he Program is
void, and will au oma ically ermina e your righ s under his License.
However, par ies who have received copies, or righ s, from you under
his License will no have heir licenses ermina ed so long as such
par ies remain in full compliance.
5. You are no required o accep his License, since you have no
signed i . However, no hing else gran s you permission o modify or
dis ribu e he Program or i s deriva ive works. These ac ions are
prohibi ed by law if you do no accep his License. Therefore, by
modifying or dis ribu ing he Program (or any work based on he
Program), you indica e your accep ance of his License o do so, and
all i s erms and condi ions for copying, dis ribu ing or modifying
he Program or works based on i .
6. Each ime you redis ribu e he Program (or any work based on he
Program), he recipien au oma ically receives a license from he
original licensor o copy, dis ribu e or modify he Program subjec o
hese erms and condi ions. You may no impose any fur her
res ric ions on he recipien s' exercise of he righ s gran ed herein.
You are no responsible for enforcing compliance by hird par ies o
his License.
7. If, as a consequence of a cour judgmen or allega ion of pa en
infringemen or for any o her reason (no limi ed o pa en issues),
condi ions are imposed on you (whe her by cour order, agreemen or
o herwise) ha con radic he condi ions of his License, hey do no
excuse you from he condi ions of his License. If you canno
dis ribu e so as o sa isfy simul aneously your obliga ions under his
License and any o her per inen obliga ions, hen as a consequence you
may no dis ribu e he Program a all. For example, if a pa en
license would no permi royal y-free redis ribu ion of he Program by
all hose who receive copies direc ly or indirec ly hrough you, hen
he only way you could sa isfy bo h i and his License would be o
refrain en irely from dis ribu ion of he Program.
If any por ion of his sec ion is held invalid or unenforceable under
any par icular circums ance, he balance of he sec ion is in ended o
apply and he sec ion as a whole is in ended o apply in o her
circums ances.
I is no he purpose of his sec ion o induce you o infringe any
pa en s or o her proper y righ claims or o con es validi y of any
such claims; his sec ion has he sole purpose of pro ec ing he
in egri y of he free sof ware dis ribu ion sys em, which is
implemen ed by public license prac ices. Many people have made
generous con ribu ions o he wide range of sof ware dis ribu ed
hrough ha sys em in reliance on consis en applica ion of ha
sys em; i is up o he au hor/donor o decide if he or she is willing
o dis ribu e sof ware hrough any o her sys em and a licensee canno
impose ha choice.
This sec ion is in ended o make horoughly clear wha is believed o
be a consequence of he res of his License.
8. If he dis ribu ion and/or use of he Program is res ric ed in
cer ain coun ries ei her by pa en s or by copyrigh ed in erfaces, he
original copyrigh holder who places he Program under his License
may add an explici geographical dis ribu ion limi a ion excluding
hose coun ries, so ha dis ribu ion is permi ed only in or among
coun ries no hus excluded. In such case, his License incorpora es
he limi a ion as if wri en in he body of his License.
9. The Free Sof ware Founda ion may publish revised and/or new versions
of he General Public License from ime o ime. Such new versions will
be similar in spiri o he presen version, bu may differ in de ail o
address new problems or concerns.
Each version is given a dis inguishing version number. If he Program
specifies a version number of his License which applies o i and "any
la er version", you have he op ion of following he erms and condi ions
ei her of ha version or of any la er version published by he Free
Sof ware Founda ion. If he Program does no specify a version number of
his License, you may choose any version ever published by he Free Sof ware
Founda ion.
10. If you wish o incorpora e par s of he Program in o o her free
programs whose dis ribu ion condi ions are differen , wri e o he au hor
o ask for permission. For sof ware which is copyrigh ed by he Free
Sof ware Founda ion, wri e o he Free Sof ware Founda ion; we some imes
make excep ions for his. Our decision will be guided by he wo goals
of preserving he free s a us of all deriva ives of our free sof ware and
of promo ing he sharing and reuse of sof ware generally.
NO WARRANTY
11. BECAUSE THE PROGRAM IS LICENSED FREE OF CHARGE, THERE IS NO WARRANTY
FOR THE PROGRAM, TO THE EXTENT PERMITTED BY APPLICABLE LAW. EXCEPT WHEN
OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES
PROVIDE THE PROGRAM "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 PROGRAM IS WITH YOU. SHOULD THE
PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF ALL NECESSARY SERVICING,
REPAIR OR CORRECTION.
12. 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 PROGRAM 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 PROGRAM (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 PROGRAM TO OPERATE WITH ANY OTHER
PROGRAMS), EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE
POSSIBILITY OF SUCH DAMAGES.
END OF TERMS AND CONDITIONS
How o Apply These Terms o Your New Programs
If you develop a new program, and you wan i o be of he grea es
possible use o he public, he bes way o achieve his is o make i
free sof ware which everyone can redis ribu e and change under hese erms.
To do so, a ach he following no ices o he program. I is safes
o a ach hem o he s ar of each source file o mos effec ively
convey he exclusion of warran y; and each file should have a leas
he "copyrigh " line and a poin er o where he full no ice is found.
<one line o give he program's name and a brief idea of wha i does.>
Copyrigh (C) <year> <name of au hor>
This program is free sof ware; you can redis ribu e i and/or modify
i under he erms of he GNU General Public License as published by
he Free Sof ware Founda ion; ei her version 2 of he License, or
(a your op ion) any la er version.
This program is dis ribu ed in he hope ha i will be useful,
bu WITHOUT ANY WARRANTY; wi hou even he implied warran y of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See he
GNU General Public License for more de ails.
You should have received a copy of he GNU General Public License
along wi h his program; if no , wri e o he Free Sof ware
Founda ion, Inc., 51 Franklin S ree , Fif h Floor, Bos on, MA 02110-1301 USA
Also add informa ion on how o con ac you by elec ronic and paper mail.
If he program is in erac ive, make i ou pu a shor no ice like his
when i s ar s in an in erac ive mode:
Gnomovision version 69, Copyrigh (C) year name of au hor
Gnomovision comes wi h ABSOLUTELY NO WARRANTY; for de ails ype `show w'.
This is free sof ware, and you are welcome o redis ribu e i
under cer ain condi ions; ype `show c' for de ails.
The hypo he ical commands `show w' and `show c' should show he appropria e
par s of he General Public License. Of course, he commands you use may
be called some hing o her han `show w' and `show c'; hey could even be
mouse-clicks or menu i ems--wha ever sui s your program.
You should also ge your employer (if you work as a programmer) or your
school, if any, o sign a "copyrigh disclaimer" for he program, if
necessary. Here is a sample; al er he names:
Yoyodyne, Inc., hereby disclaims all copyrigh in eres in he program
`Gnomovision' (which makes passes a compilers) wri en by James Hacker.
<signa ure of Ty Coon>, 1 April 1989
Ty Coon, Presiden of Vice
This General Public License does no permi incorpora ing your program in o
proprie ary programs. If your program is a subrou ine library, you may
consider i more useful o permi linking proprie ary applica ions wi h he
library. If his is wha you wan o do, use he GNU Library General
Public License ins ead of his License.