Finally, every program is threatened constantly by software
patents. States should not allow patents to restrict
development and use of software on general-purpose
omputers, but in those that do, we wish to avoid the special
anger that patents applied to a free program could make it
ffectively proprietary. To prevent this, the GPL assures that
atents cannot be used to render the program non-free. he
precise terms and conditions for copying, distribution and
modification follow.
termS anD conDitionS
0. Definitions.
“This License” refers to version 3 of the GNU General Public
License.
“Copyright” also means copyright-like laws that apply
to other kinds of works, such as semiconductor masks.
“The Program” refers to any copyrightable work licensed
under this License. Each licensee is addressed as “you”.
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A “covered work” means either the unmodified Program or a
work based on the Program.
To “propagate” a work means to do anything with it that,
without permission, would make you directly or secondarily
liable for infringement under applicable copyright law, except
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Propagation includes copying, distribution (with or without
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to the extent that warranties are provided), that licensees
may convey the work under this License, and how to view
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1. Source code.
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The “System Libraries” of an executable work include
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which are used unmodified in performing those activities but
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is specifically designed to require, such as by intimate data
communication or control flow between those subprograms
and other parts of the work.
The Corresponding Source need not include anything that
users can regenerate automatically from other parts of the
Corresponding Source. The Corresponding Source for a
work in source code form is that same work.
2. Basic permissions.
All rights granted under this License are granted for the term
of copyright on the Program, and are irrevocable provided
the stated conditions are met. This License explicitly affirms
your unlimited permission to run the unmodified Program.
The output from running a covered work is covered by this
License only if the output, given its content, constitutes a
covered work. This License acknowledges your rights of fair
use or other equivalent, as provided by copyright law.
You may make, run and propagate covered works that you
do not convey, without conditions so long as your license
otherwise remains in force. You may convey covered works to
others for the sole purpose of having them make modifications
exclusively for you, or provide you with facilities for running
those works, provided that you comply with the terms of this
License in conveying all material for which you do not control
copyright. Those thus making or running the covered works for
you must do so exclusively on your behalf, under your direction
and control, on terms that prohibit them from making any
copies of your copyrighted material outside their relationship
with you. Conveying under any other circumstances
is permitted solely under the conditions stated below.
Sublicensing is not allowed; section 10 makes it unnecessary.
3. protecting users’ Legal rights from anti-
circumvention Law.
No covered work shall be deemed part of an effective
technological measure under any applicable law fulfilling
obligations under article 11 of the WIPO copyright treaty
adopted on 20 December 1996, or similar laws prohibiting or
restricting circumvention of such measures.
When you convey a covered work, you waive any legal
power to forbid circumvention of technological measures to
the extent such circumvention is effected by exercising rights
under this License with respect to the covered work, and
you disclaim any intention to limit operation or modification of
the work as a means of enforcing, against the work’s users,
your or third parties’ legal rights to forbid circumvention of
technological measures.
4. conveying verbatim copies.
You may convey verbatim copies of the Program’s source
code as you receive it, in any medium, provided that you
conspicuously and appropriately publish on each copy an
appropriate copyright notice; keep intact all notices stating
that this License and any non-permissive terms added
in accord with section 7 apply to the code; keep intact
all notices of the absence of any warranty; and give all
recipients a copy of this License along with the Program.
You may charge any price or no price for each copy that you
convey, and you may offer support or warranty protection
for a fee.