6
To protect each distr ibutor, we want to make it ve ry clear that the re is no warrant y for the free libr ary. Also,
if the librar y is modied by someone e lse and passed on, th e recipients sho uld know that what the y have is
not the original ve rsion, so that the o riginal author ’s reputation wi ll not be affected by pr oblems that might b e
introduced by othe rs.
Finally, softwa re patents pose a cons tant threat to th e existence of any fre e program. We wish to ma ke sure that
a company cannot effe ctively rest rict the users of a f ree program by obt aining a restr ictive license fr om a patent
holder. Therefore , we insist that any pat ent license obtain ed for a version of the li brary must be co nsistent with
the full freedom of u se specied in this li cense.
Most GNU soft ware, includin g some libraries , is covered by the ordi nary GNU Gene ral Public Licens e. This
license, the GNU L esser General P ublic License, app lies to certain d esignated libra ries, and is quite d ifferent
from the ordinar y General Pu blic License. We use this l icense for certa in libraries in or der to permit lin king
those librari es into non-free pr ograms.
When a program i s linked with a libra ry, whether st atically or using a sh ared library, th e combination of the t wo
is legally speak ing a combined work , a derivative of th e original libra ry. The ordinar y General Publi c License
therefore per mits such linkin g only if the entire com bination ts it s criteria of fre edom. The Lesser G eneral
Public License per mits more lax cr iteria for link ing other code with t he library.
We call this license the “ Lesser” Gener al Public License b ecause it does Less to p rotect the user’s f reedom than
the ordinary G eneral Public L icense. It also prov ides other free sof tware develop ers Less of an advan tage over
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for many librari es. However, the Lesser li cense provides adv antages in cert ain special circum stances.
For example, on r are occasions, t here may be a special ne ed to encourage the wi dest possible use of a ce rtain
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case, there is li ttle to gain by limi ting the free libr ary to free sof tware only, so we use the L esser General P ublic
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In other cases, p ermission to use a pa rticular libr ary in non-fre e programs enab les a greater numbe r of people
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enables many more p eople to use the whole G NU operating sy stem, as well as i ts variant, the G NU/Linux
operating sys tem.
Although the Les ser General Pub lic License is Less pro tective of the user s’ freedom, it doe s ensure that the use r
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GNU LESSER GEN ERAL PUBLI C LICENSE
TERMS AND COND ITIONS FOR COPYI NG, DISTRI BUTION AND MOD IFICATION
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The “Librar y”, below, refers to any s uch software li brary or work w hich has been dist ributed under t hese
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