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GNU Library General Public License
Version 2, June 1991
Copyright (C) 1991 Free Software Foundation, Inc.
59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
Everyone is permitted to copy and distribute verbatim copies of this license document,
but changing it is not allowed.
[This is the first released version of the library GPL. It is numbered 2 because it goes
with version 2 of the ordinary GPL.]
PREAMBLE: The licenses for most software are designed to take away your freedom to
share and change it. By contrast, the GNU General Public Licenses are intended to guar-
antee your freedom to share and change free software--to ma ke sure the software is free
for all its users.
This license, the Library General Public License, applies to some specially designated
Free Software Foundation software, and to a ny other libraries whose authors decide to
use it. You can use it for your libraries, too.
When we speak of free software, we are referring to freedom, not price. Our General
Public Licenses are design ed to make sure that you have the freedom to dist ribute cop-
ies of free software (and charge for this servic e if you wish), that you r eceive source code
or can get it if you want it, that you can change the software or use pieces of it in new
free programs; and that you know you can do the se things.
To protect your rights, we need to make restrictions that forbid anyone to deny you
these rights or to ask you to surrender the rights. These restrictions tr anslate to certain
responsibilities for you if you distribute copies of the library, or if you modify it. For ex-
ample, if you distribute copies of the library, w hether gratis or for a fee, you m ust give
the recipients all the rights that we gave you. You must make sure that they, too, receive
or can get the source code. If you link a program with the library, you must provide
complete object files to the recipients so that they can relink them with the library, after
making changes to the library and recompiling it. And you must show them t hese terms
so they know their rights.
Our method of protecting your rights has two s teps: (1) copyright the library, and (2)
offer you this license which gives you legal permissi on to copy, distribute and/or mod-
ify the library.
Also, for each distributor's protection, we want to make certain that everyone under-
stands that there is no warranty for this free library. If the library is modified by some-
one else and passed on, we want its recipients to know that what they have is not the
original version, so that any problems introduced by others will not reflect on the orig-
inal authors' reputations.
Finally, any free program is threatened constantly by softwa re patents. We wish to
avoid the danger that companies distributing free software will individually obtain
patent licenses, thus in effect transforming the program into proprietary software. To
prevent this, we have made it cle ar that any patent must b e licensed for everyone's free
use or not licensed at all.
Most GNU software, including some libraries, is covered by the ordinary GNU General
Public License, which was designed for utility programs. This license, the GNU Library
General Public License, applies to certain designated libraries. This license is quite dif-
ferent from the ordinary one; be sure to read it in full, and don't assume that anything
in it is the same as in the ordinary license.