iv
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modiedversionoftheLibrary.
Theprecisetermsandconditionsforcopying,distributionandmodication
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.
GNULESSERGENERALPUBLICLICENSE
TERMSANDCONDITIONS FOR COPYING, DISTRIBUTIONAND
MODIFICATION
0.  ThisLicenseAgreementappliestoanysoftwarelibr aryorother
programwhichcontainsanoticeplaced bythecopyrightholder
orother authorized par ty saying it maybe distr ibuted under
thetermsofthisLesser GeneralPublicLicense(also called“this
License”).Eachlicenseeisaddressedas“you”.
A“librar y”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 modications
and/or translated straightforwardly into another language.
(Hereinafter,translationisincludedwithoutlimitationintheterm
“modication”.)
 “Sourcecode”foraworkmeansthepreferredformofthework
formakingmodicationstoit.Foralibrary,completesourcecode
meansallthe sourcecode forall modulesitcontains, plusany
associatedinterfacedenitionles,plusthescriptsusedtocontrol
compilationandinstallationofthelibrary.
 Activitiesotherthancopying,distributionandmodication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tr ansferring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modicationsorworkunderthetermsofSection
1above,providedthatyoualsomeetalloftheseconditions:
 a)Themodiedworkmustitselfbeasoftwarelibrary.
 b)Youmustcausethelesmodiedtocarryprominent notices
statingthatyouchangedtheles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modied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-dened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 modiedwork asa whole.If
identiable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separ ate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ver sion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.