User Manual

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You should also get your employer (if you work as a
programmer) or your school, if any, to sign a "copy-
right disclaimer" for the program, if necessary. Here
is a sample; alter the names:
Yoyodyne, Inc., hereby disclaims all copyright
interest in the program `Gnomovision`
(which makes passes at compilers) written
by James Hacker.
signature of Ty Coon, 1 April 1989
Ty Coon, President of Vice
This General Public License does not permit incor-
porating your program into proprietary programs. If
your program is a subroutine library, you may con-
sider it more useful to permit linking proprietary
applications with the library. If this is what you want
to do, use the GNU Lesser General Public License
instead of this License.
GNU GENERAL PUBLIC LICENSE
Version 3, 29 June 2007
Copyright © 2007 Free Software Foundation, Inc.
<http://fsf.org/>
Everyone is permitted to copy and distribute verba-
tim copies of this license document, but changing it
is not allowed.
Preamble
The GNU General Public License is a free, copyleft
license for software and other kinds of works.
The licenses for most software and other practical
works are designed to take away your freedom to
share and change the works. By contrast, the GNU
General Public License is intended to guarantee
your freedom to share and change all versions of a
program--to make sure it remains free software for
all its users. We, the Free Software Foundation, use
the GNU General Public License for most of our
software; it applies also to any other work released
this way by its authors. You can apply it to your pro-
grams, too.
When we speak of free software, we are referring to
freedom, not price. Our General Public Licenses are
designed to make sure that you have the freedom to
distribute copies of free software (and charge for
them if you wish), that you receive source code or
can get it if you want it, that you can change the soft-
ware or use pieces of it in new free programs, and
that you know you can do these things.
To protect your rights, we need to prevent others
from denying you these rights or asking you to sur-
render the rights. Therefore, you have certain
responsibilities if you distribute copies of the soft-
ware, or if you modify it: responsibilities to respect
the freedom of others.
For example, if you distribute copies of such a pro-
gram, whether gratis or for a fee, you must pass on
to the recipients the same freedoms that you
received. You must make sure that they, too, receive
or can get the source code. And you must show
them these terms so they know their rights.
Developers that use the GNU GPL protect your
rights with two steps: (1) assert copyright on the
software, and (2) offer you this License giving you
legal permission to copy, distribute and/or modify it.
For the developers' and authors' protection, the GPL
clearly explains that there is no warranty for this free
software. For both users' and authors' sake, the GPL
requires that modified versions be marked as
changed, so that their problems will not be attributed
erroneously to authors of previous versions.
Some devices are designed to deny users access to
install or run modified versions of the software inside
them, although the manufacturer can do so. This is
fundamentally incompatible with the aim of protect-
ing users' freedom to change the software. The sys-
tematic pattern of such abuse occurs in the area of
products for individuals to use, which is precisely
where it is most unacceptable. Therefore, we have
designed this version of the GPL to prohibit the
practice for those products. If such problems arise
substantially in other domains, we stand ready to
extend this provision to those domains in future ver-
sions of the GPL, as needed to protect the freedom
of users.
Finally, every program is threatened constantly by
software patents. States should not allow patents to
restrict development and use of software on gen-
eral-purpose computers, but in those that do, we
wish to avoid the special danger that patents applied
to a free program could make it effectively proprie-
tary. To prevent this, the GPL assures that patents
cannot be used to render the program non-free.
The precise terms and conditions for copying, distri-
bution and modification follow.
TERMS AND CONDITIONS
0. Definitions.
“This License” refers to version 3 of the GNU Gen-
eral Public License.
“Copyright” also means copyright-like laws that
apply to other kinds of works, such as semiconduc-
tor masks.
“The Program” refers to any copyrightable work
licensed under this License. Each licensee is
addressed as “you”. “Licensees” and “recipients”
may be individuals or organizations.
To “modify” a work means to copy from or adapt all
or part of the work in a fashion requiring copyright
permission, other than the making of an exact copy.
The resulting work is called a “modified version” of
the earlier work or a work “based on” the earlier
work.
A “covered work” means either the unmodified Pro-
gram 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 executing it on a computer or
modifying a private copy. Propagation includes copy-
ing, distribution (with or without modification), mak-
ing available to the public, and in some countries
other activities as well.
To “convey” a work means any kind of propagation
that enables other parties to make or receive copies.
Mere interaction with a user through a computer net-
work, with no transfer of a copy, is not conveying.
An interactive user interface displays “Appropriate
Legal Notices” to the extent that it includes a con-
venient and prominently visible feature that (1) dis-
plays an appropriate copyright notice, and (2) tells
the user that there is no warranty for the work
(except to the extent that warranties are provided),
that licensees may convey the work under this
License, and how to view a copy of this License. If
the interface presents a list of user commands or
options, such as a menu, a prominent item in the list
meets this criterion.
1. Source Code.
The “source code” for a work means the preferred
form of the work for making modifications to it.
“Object code” means any non-source form of a
work.
A “Standard Interface” means an interface that either
is an official standard defined by a recognized stand-
ards body, or, in the case of interfaces specified for a
particular programming language, one that is widely
used among developers working in that language.
The “System Libraries” of an executable work
include anything, other than the work as a whole,
that (a) is included in the normal form of packaging
a Major Component, but which is not part of that
Major Component, and (b) serves only to enable
use of the work with that Major Component, or to
implement a Standard Interface for which an imple-
mentation is available to the public in source code
form. A “Major Component”, in this context, means a
major essential component (kernel, window system,
and so on) of the specific operating system (if any)
on which the executable work runs, or a compiler