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 translate to certain responsibilities for you if you distribute copies of the library, or if you modify it.
For example, if you distribute copies of the library, whether gratis or for a fee, you must 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 DSURJUDPZLWKWKHOLEUDU\\RXPXVWSURYLGHFRPSOHWHREMHFWÀOHVWRWKHUHFLSLHQWVVRWKDWWKH\FDQUHOLQN them with the library, after making changes to the library and recompiling it. And you must show them these terms so they know their rights.
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Also, for each distributor’s protection, we want to make certain that everyone understands that there is no ZDUUDQW\IRUWKLVIUHHOLEUDU\,IWKHOLEUDU\LVPRGLÀHGE\VRPHRQHHOVHDQGSDVVHGRQZHZDQWLWVUHFLSLHQWV to know that what they have is not the original version, so that any problems introduced by others will not
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Finally, any free program is threatened constantly by software 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 clear that any patent must be 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 GHVLJQDWHGOLEUDULHV7KLVOLFHQVHLVTXLWHGLIIHUHQWIURPWKHRUGLQDU\RQH EHVXUHWRUHDGLWLQIXOODQGGRQ·W assume that anything in it is the same as in the ordinary license.
The reason we have a separate public license for some libraries is that they blur the distinction we usually make between modifying or adding to a program and simply using it. Linking a program with a library, without changing the library, is in some sense simply using the library, and is analogous to running a utility program or application program. However, in a textual and legal sense, the linked executable is a combined work, a derivative of the original library, and the ordinary General Public License treats it as such.
Because of this blurred distinction, using the ordinary General Public License for libraries did not effectively promote software sharing, because most developers did not use the libraries. We concluded that weaker conditions might promote sharing better.
+RZHYHUXQUHVWULFWHGOLQNLQJRIQRQIUHHSURJUDPVZRXOGGHSULYHWKHXVHUVRIWKRVHSURJUDPVRIDOOEHQHÀW from the free status of the libraries themselves. This Library General Public License is intended to permit developers of
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Note that it is possible for a library to be covered by the ordinary General Public License rather than by this special one.
GNU LIBRARY GENERAL PUBLIC LICENSE
TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION
0.This License Agreement applies to any software library which contains a notice placed by the copyright holder or other authorized party saying it may be distributed under the terms of this Library General
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