7
1. You may copy and distribute ver batim copies of the Libr ary’s complete sou rce 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 wa rranty; keep int act all the notices tha t refer to this License and t o the absence of
any warranty; an d distribute a copy of t his License along wit h the Library.
You may charge a fee for the physical a ct of transferri ng a copy, and you may at your option offer w arranty
protection in exchan ge for a fee.
2. You may mod ify your copy or copies of the Lib rary or any port ion of it, thus forming a wor k based on the
Library, and copy and dis tribute such modific ations or work under the te rms of Section 1 above, pr ovided
that you also meet all of thes e conditions:
a) The modified work must i tself be a softw are library.
b) You mus t cause the files modifi ed to carry promi nent notices statin g that you changed the files a nd the
date of any change.
c) You must cause the whole of the work to b e licensed at no charge to all th ird parties unde r the terms
of this License.
d) If a facility in the modified Library refers to a function or a table of data to be supplied by an application
program that uses th e facility, other than as a n argument passed whe n the facility is invoked , then you
must make a good faith ef fort to ensure tha t, in the event an applic ation does not supply su ch function
or table, the facili ty still operat es, and perfor ms whatever par t of its purpose rema ins meaningful.
(For example, a func tion in a library to co mpute square root s has a purpose that is en tirely well-defi ned
independent of the app lication. Ther efore, Subsect ion 2d requires tha t any application- supplied functi on
or table used by this function must be optional: if the application does not supply it, the square root
function must st ill compute square r oots.)
These requirements apply to the modified work as a whole. If identifiable sections of that work are not
derived from the Li brary, and can be re asonably consider ed independent a nd separate work s in themselves,
then this License, and i ts terms, do not apply to tho se sections when you distr ibute them as separa te
works. But when yo u distribute the s ame sections as par t of a whole which is a work ba sed on the Librar y,
the distributio n of the whole must be on the ter ms of this License, whose per missions for other license es
extend to the entir e whole, and thus to ea ch and every par t regardless of who w rote it.
Thus, it is not the inten t of this section to claim r ights or contest you r rights to work wr itten entirel y by you;
rather, the intent is to exe rcise the right to control t he distribution of d erivative or collect ive works based
on the Library.
In addition, mere ag gregation of another wor k not based on the Librar y with the Librar y (or with a work
based on the Librar y) on a volume of a stora ge or distribut ion medium does not br ing the other work u nder
the scope of this License.
3. You may opt to a pply the terms of the ordina ry GNU General Publ ic License instead of this Lice nse to a
given copy of the Librar y. To do this, you must alter all the not ices that refer to this License , so that they
refer to the ordinar y GNU General Publi c License, version 2, i nstead 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 version
instead if you wish.) Do not ma ke any other change in the se notices.
Once this change is made in a giv en copy, it is irrevers ible for that copy, so the ordi nary GNU Gene ral Public
License applies to all sub sequent copies and de rivative work s made from that copy.
This option is useful whe n you wish to copy part of the code of th e Library into a progr am that is not a
library.
4. You may copy and distribute the Lib rary (or a portion or de rivative of it, under S ection 2) in object code
or executable form und er the terms of Sections 1 a nd 2 above provided that you accompa ny it with the
complete correspond ing machine-readable so urce code, which must be dis tributed under the ter ms of
Sections 1 and 2 above on a me dium customaril y used for softwar e interchange.
If distribution of object code is made by offering access to copy from a designated place, then offering
equivalent access to copy th e source code from the same pl ace satisfies the requir ement to distribu te the
source code, even though t hird parties a re not compelled to copy th e source along with th e object code.
5. A program that contains n o derivative of any po rtion of the Libr ary, but is design ed to work with the Li brary
by being compiled or linked w ith it, is called a “w ork that uses the Lib rary”. Such a work , in isolation, is not a
derivative work of th e Library, and the refore falls out side the scope of this Lice nse.
However, linking a “work th at uses the Library ” with the Librar y creates an executable t hat is a derivative
of the Library (be cause it contains por tions of the Librar y), rather than a “work tha t uses the library ”. The
executable is therefo re covered by this Licens e.