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1. The GNU General Public License {#the-gnu-general-public-license .chapter}
=================================

Version 3, 29 June 2007

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|                                      | Copyright © 2007 Free Software Found |
|                                      | ation, Inc. http://fsf.org/          |
|                                      | 51 Franklin St., Floor 5, Boston, MA |
|                                      |  02110-1335, USA                     |
|                                      |                                      |
|                                      | Everyone is permitted to copy and di |
|                                      | stribute verbatim copies of this lic |
|                                      | ense document, but changing it is no |
|                                      | t allowed.                           |
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Preamble {#preamble .heading}
--------

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 programs, 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 software 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 surrender the rights. Therefore, you have
certain responsibilities if you distribute copies of the software, or if
you modify it: responsibilities to respect the freedom of others.

For example, if you distribute copies of such a program, 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 protecting
users’ freedom to change the software. The systematic 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 versions 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 general-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 proprietary. To prevent this, the GPL assures that
patents cannot be used to render the program non-free.

The precise terms and conditions for copying, distribution and
modification follow.

TERMS AND CONDITIONS {#terms-and-conditions .heading}
--------------------

1.  **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”. “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 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 executing it on
    a computer or modifying a private copy. Propagation includes
    copying, distribution (with or without modification), making
    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 network, with no transfer of a copy, is
    not conveying.

    An interactive user interface displays “Appropriate Legal Notices”
    to the extent that it includes a convenient and prominently visible
    feature that (1) displays 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.

2.  **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 standards 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
    implementation 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 used to produce the work, or an object code interpreter
    used to run it.

    The “Corresponding Source” for a work in object code form means all
    the source code needed to generate, install, and (for an
    executable work) run the object code and to modify the work,
    including scripts to control those activities. However, it does not
    include the work’s System Libraries, or general-purpose tools or
    generally available free programs which are used unmodified in
    performing those activities but which are not part of the work. For
    example, Corresponding Source includes interface definition files
    associated with source files for the work, and the source code for
    shared libraries and dynamically linked subprograms that the work 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.

3.  **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.

4.  **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.

5.  **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.

6.  **Conveying Modified Source Versions.**

    You may convey a work based on the Program, or the modifications to
    produce it from the Program, in the form of source code under the
    terms of section 4, provided that you also meet all of these
    conditions:

    1.  The work must carry prominent notices stating that you modified
        it, and giving a relevant date.
    2.  The work must carry prominent notices stating that it is
        released under this License and any conditions added under
        section 7. This requirement modifies the requirement in section
        4 to “keep intact all notices”.
    3.  You must license the entire work, as a whole, under this License
        to anyone who comes into possession of a copy. This License will
        therefore apply, along with any applicable section 7 additional
        terms, to the whole of the work, and all its parts, regardless
        of how they are packaged. This License gives no permission to
        license the work in any other way, but it does not invalidate
        such permission if you have separately received it.
    4.  If the work has interactive user interfaces, each must display
        Appropriate Legal Notices; however, if the Program has
        interactive interfaces that do not display Appropriate Legal
        Notices, your work need not make them do so.

    A compilation of a covered work with other separate and independent
    works, which are not by their nature extensions of the covered work,
    and which are not combined with it such as to form a larger program,
    in or on a volume of a storage or distribution medium, is called an
    “aggregate” if the compilation and its resulting copyright are not
    used to limit the access or legal rights of the compilation’s users
    beyond what the individual works permit. Inclusion of a covered work
    in an aggregate does not cause this License to apply to the other
    parts of the aggregate.

7.  **Conveying Non-Source Forms.**

    You may convey a covered work in object code form under the terms of
    sections 4 and 5, provided that you also convey the machine-readable
    Corresponding Source under the terms of this License, in one of
    these ways:

    1.  Convey the object code in, or embodied in, a physical product
        (including a physical distribution medium), accompanied by the
        Corresponding Source fixed on a durable physical medium
        customarily used for software interchange.
    2.  Convey the object code in, or embodied in, a physical product
        (including a physical distribution medium), accompanied by a
        written offer, valid for at least three years and valid for as
        long as you offer spare parts or customer support for that
        product model, to give anyone who possesses the object code
        either (1) a copy of the Corresponding Source for all the
        software in the product that is covered by this License, on a
        durable physical medium customarily used for software
        interchange, for a price no more than your reasonable cost of
        physically performing this conveying of source, or (2) access to
        copy the Corresponding Source from a network server at
        no charge.
    3.  Convey individual copies of the object code with a copy of the
        written offer to provide the Corresponding Source. This
        alternative is allowed only occasionally and noncommercially,
        and only if you received the object code with such an offer, in
        accord with subsection 6b.
    4.  Convey the object code by offering access from a designated
        place (gratis or for a charge), and offer equivalent access to
        the Corresponding Source in the same way through the same place
        at no further charge. You need not require recipients to copy
        the Corresponding Source along with the object code. If the
        place to copy the object code is a network server, the
        Corresponding Source may be on a different server (operated by
        you or a third party) that supports equivalent copying
        facilities, provided you maintain clear directions next to the
        object code saying where to find the Corresponding Source.
        Regardless of what server hosts the Corresponding Source, you
        remain obligated to ensure that it is available for as long as
        needed to satisfy these requirements.
    5.  Convey the object code using peer-to-peer transmission, provided
        you inform other peers where the object code and Corresponding
        Source of the work are being offered to the general public at no
        charge under subsection 6d.

    A separable portion of the object code, whose source code is
    excluded from the Corresponding Source as a System Library, need not
    be included in conveying the object code work.

    A “User Product” is either (1) a “consumer product”, which means any
    tangible personal property which is normally used for personal,
    family, or household purposes, or (2) anything designed or sold for
    incorporation into a dwelling. In determining whether a product is a
    consumer product, doubtful cases shall be resolved in favor
    of coverage. For a particular product received by a particular user,
    “normally used” refers to a typical or common use of that class of
    product, regardless of the status of the particular user or of the
    way in which the particular user actually uses, or expects or is
    expected to use, the product. A product is a consumer product
    regardless of whether the product has substantial commercial,
    industrial or non-consumer uses, unless such uses represent the only
    significant mode of use of the product.

    “Installation Information” for a User Product means any methods,
    procedures, authorization keys, or other information required to
    install and execute modified versions of a covered work in that User
    Product from a modified version of its Corresponding Source. The
    information must suffice to ensure that the continued functioning of
    the modified object code is in no case prevented or interfered with
    solely because modification has been made.

    If you convey an object code work under this section in, or with, or
    specifically for use in, a User Product, and the conveying occurs as
    part of a transaction in which the right of possession and use of
    the User Product is transferred to the recipient in perpetuity or
    for a fixed term (regardless of how the transaction is
    characterized), the Corresponding Source conveyed under this section
    must be accompanied by the Installation Information. But this
    requirement does not apply if neither you nor any third party
    retains the ability to install modified object code on the User
    Product (for example, the work has been installed in ROM).

    The requirement to provide Installation Information does not include
    a requirement to continue to provide support service, warranty, or
    updates for a work that has been modified or installed by the
    recipient, or for the User Product in which it has been modified
    or installed. Access to a network may be denied when the
    modification itself materially and adversely affects the operation
    of the network or violates the rules and protocols for communication
    across the network.

    Corresponding Source conveyed, and Installation Information
    provided, in accord with this section must be in a format that is
    publicly documented (and with an implementation available to the
    public in source code form), and must require no special password or
    key for unpacking, reading or copying.

8.  **Additional Terms.**

    “Additional permissions” are terms that supplement the terms of this
    License by making exceptions from one or more of its conditions.
    Additional permissions that are applicable to the entire Program
    shall be treated as though they were included in this License, to
    the extent that they are valid under applicable law. If additional
    permissions apply only to part of the Program, that part may be used
    separately under those permissions, but the entire Program remains
    governed by this License without regard to the
    additional permissions.

    When you convey a copy of a covered work, you may at your option
    remove any additional permissions from that copy, or from any part
    of it. (Additional permissions may be written to require their own
    removal in certain cases when you modify the work.) You may place
    additional permissions on material, added by you to a covered work,
    for which you have or can give appropriate copyright permission.

    Notwithstanding any other provision of this License, for material
    you add to a covered work, you may (if authorized by the copyright
    holders of that material) supplement the terms of this License with
    terms:

    1.  Disclaiming warranty or limiting liability differently from the
        terms of sections 15 and 16 of this License; or
    2.  Requiring preservation of specified reasonable legal notices or
        author attributions in that material or in the Appropriate Legal
        Notices displayed by works containing it; or
    3.  Prohibiting misrepresentation of the origin of that material, or
        requiring that modified versions of such material be marked in
        reasonable ways as different from the original version; or
    4.  Limiting the use for publicity purposes of names of licensors or
        authors of the material; or
    5.  Declining to grant rights under trademark law for use of some
        trade names, trademarks, or service marks; or
    6.  Requiring indemnification of licensors and authors of that
        material by anyone who conveys the material (or modified
        versions of it) with contractual assumptions of liability to the
        recipient, for any liability that these contractual assumptions
        directly impose on those licensors and authors.

    All other non-permissive additional terms are considered “further
    restrictions” within the meaning of section 10. If the Program as
    you received it, or any part of it, contains a notice stating that
    it is governed by this License along with a term that is a further
    restriction, you may remove that term. If a license document
    contains a further restriction but permits relicensing or conveying
    under this License, you may add to a covered work material governed
    by the terms of that license document, provided that the further
    restriction does not survive such relicensing or conveying.

    If you add terms to a covered work in accord with this section, you
    must place, in the relevant source files, a statement of the
    additional terms that apply to those files, or a notice indicating
    where to find the applicable terms.

    Additional terms, permissive or non-permissive, may be stated in the
    form of a separately written license, or stated as exceptions; the
    above requirements apply either way.

9.  **Termination.**

    You may not propagate or modify a covered work except as expressly
    provided under this License. Any attempt otherwise to propagate or
    modify it is void, and will automatically terminate your rights
    under this License (including any patent licenses granted under the
    third paragraph of section 11).

    However, if you cease all violation of this License, then your
    license from a particular copyright holder is reinstated (a)
    provisionally, unless and until the copyright holder explicitly and
    finally terminates your license, and (b) permanently, if the
    copyright holder fails to notify you of the violation by some
    reasonable means prior to 60 days after the cessation.

    Moreover, your license from a particular copyright holder is
    reinstated permanently if the copyright holder notifies you of the
    violation by some reasonable means, this is the first time you have
    received notice of violation of this License (for any work) from
    that copyright holder, and you cure the violation prior to 30 days
    after your receipt of the notice.

    Termination of your rights under this section does not terminate the
    licenses of parties who have received copies or rights from you
    under this License. If your rights have been terminated and not
    permanently reinstated, you do not qualify to receive new licenses
    for the same material under section 10.

10. **Acceptance Not Required for Having Copies.**

    You are not required to accept this License in order to receive or
    run a copy of the Program. Ancillary propagation of a covered work
    occurring solely as a consequence of using peer-to-peer transmission
    to receive a copy likewise does not require acceptance. However,
    nothing other than this License grants you permission to propagate
    or modify any covered work. These actions infringe copyright if you
    do not accept this License. Therefore, by modifying or propagating a
    covered work, you indicate your acceptance of this License to do so.

11. **Automatic Licensing of Downstream Recipients.**

    Each time you convey a covered work, the recipient automatically
    receives a license from the original licensors, to run, modify and
    propagate that work, subject to this License. You are not
    responsible for enforcing compliance by third parties with
    this License.

    An “entity transaction” is a transaction transferring control of an
    organization, or substantially all assets of one, or subdividing an
    organization, or merging organizations. If propagation of a covered
    work results from an entity transaction, each party to that
    transaction who receives a copy of the work also receives whatever
    licenses to the work the party’s predecessor in interest had or
    could give under the previous paragraph, plus a right to possession
    of the Corresponding Source of the work from the predecessor in
    interest, if the predecessor has it or can get it with
    reasonable efforts.

    You may not impose any further restrictions on the exercise of the
    rights granted or affirmed under this License. For example, you may
    not impose a license fee, royalty, or other charge for exercise of
    rights granted under this License, and you may not initiate
    litigation (including a cross-claim or counterclaim in a lawsuit)
    alleging that any patent claim is infringed by making, using,
    selling, offering for sale, or importing the Program or any portion
    of it.

12. **Patents.**

    A “contributor” is a copyright holder who authorizes use under this
    License of the Program or a work on which the Program is based. The
    work thus licensed is called the contributor’s
    “contributor version”.

    A contributor’s “essential patent claims” are all patent claims
    owned or controlled by the contributor, whether already acquired or
    hereafter acquired, that would be infringed by some manner,
    permitted by this License, of making, using, or selling its
    contributor version, but do not include claims that would be
    infringed only as a consequence of further modification of the
    contributor version. For purposes of this definition, “control”
    includes the right to grant patent sublicenses in a manner
    consistent with the requirements of this License.

    Each contributor grants you a non-exclusive, worldwide, royalty-free
    patent license under the contributor’s essential patent claims, to
    make, use, sell, offer for sale, import and otherwise run, modify
    and propagate the contents of its contributor version.

    In the following three paragraphs, a “patent license” is any express
    agreement or commitment, however denominated, not to enforce a
    patent (such as an express permission to practice a patent or
    covenant not to sue for patent infringement). To “grant” such a
    patent license to a party means to make such an agreement or
    commitment not to enforce a patent against the party.

    If you convey a covered work, knowingly relying on a patent license,
    and the Corresponding Source of the work is not available for anyone
    to copy, free of charge and under the terms of this License, through
    a publicly available network server or other readily accessible
    means, then you must either (1) cause the Corresponding Source to be
    so available, or (2) arrange to deprive yourself of the benefit of
    the patent license for this particular work, or (3) arrange, in a
    manner consistent with the requirements of this License, to extend
    the patent license to downstream recipients. “Knowingly relying”
    means you have actual knowledge that, but for the patent license,
    your conveying the covered work in a country, or your recipient’s
    use of the covered work in a country, would infringe one or more
    identifiable patents in that country that you have reason to believe
    are valid.

    If, pursuant to or in connection with a single transaction or
    arrangement, you convey, or propagate by procuring conveyance of, a
    covered work, and grant a patent license to some of the parties
    receiving the covered work authorizing them to use, propagate,
    modify or convey a specific copy of the covered work, then the
    patent license you grant is automatically extended to all recipients
    of the covered work and works based on it.

    A patent license is “discriminatory” if it does not include within
    the scope of its coverage, prohibits the exercise of, or is
    conditioned on the non-exercise of one or more of the rights that
    are specifically granted under this License. You may not convey a
    covered work if you are a party to an arrangement with a third party
    that is in the business of distributing software, under which you
    make payment to the third party based on the extent of your activity
    of conveying the work, and under which the third party grants, to
    any of the parties who would receive the covered work from you, a
    discriminatory patent license (a) in connection with copies of the
    covered work conveyed by you (or copies made from those copies),
    or (b) primarily for and in connection with specific products or
    compilations that contain the covered work, unless you entered into
    that arrangement, or that patent license was granted, prior to 28
    March 2007.

    Nothing in this License shall be construed as excluding or limiting
    any implied license or other defenses to infringement that may
    otherwise be available to you under applicable patent law.

13. **No Surrender of Others’ Freedom.**

    If conditions are imposed on you (whether by court order, agreement
    or otherwise) that contradict the conditions of this License, they
    do not excuse you from the conditions of this License. If you cannot
    convey a covered work so as to satisfy simultaneously your
    obligations under this License and any other pertinent obligations,
    then as a consequence you may not convey it at all. For example, if
    you agree to terms that obligate you to collect a royalty for
    further conveying from those to whom you convey the Program, the
    only way you could satisfy both those terms and this License would
    be to refrain entirely from conveying the Program.

14. **Use with the GNU Affero General Public License.**

    Notwithstanding any other provision of this License, you have
    permission to link or combine any covered work with a work licensed
    under version 3 of the GNU Affero General Public License into a
    single combined work, and to convey the resulting work. The terms of
    this License will continue to apply to the part which is the covered
    work, but the special requirements of the GNU Affero General Public
    License, section 13, concerning interaction through a network will
    apply to the combination as such.

15. **Revised Versions of this License.**

    The Free Software Foundation may publish revised and/or new versions
    of the GNU General Public License from time to time. Such new
    versions will be similar in spirit to the present version, but may
    differ in detail to address new problems or concerns.

    Each version is given a distinguishing version number. If the
    Program specifies that a certain numbered version of the GNU General
    Public License “or any later version” applies to it, you have the
    option of following the terms and conditions either of that numbered
    version or of any later version published by the Free
    Software Foundation. If the Program does not specify a version
    number of the GNU General Public License, you may choose any version
    ever published by the Free Software Foundation.

    If the Program specifies that a proxy can decide which future
    versions of the GNU General Public License can be used, that proxy’s
    public statement of acceptance of a version permanently authorizes
    you to choose that version for the Program.

    Later license versions may give you additional or
    different permissions. However, no additional obligations are
    imposed on any author or copyright holder as a result of your
    choosing to follow a later version.

16. **Disclaimer of Warranty.**

    THERE IS NO WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY
    APPLICABLE LAW. EXCEPT WHEN OTHERWISE STATED IN WRITING THE
    COPYRIGHT HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM “AS IS”
    WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED OR IMPLIED,
    INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
    MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE ENTIRE
    RISK AS TO THE QUALITY AND PERFORMANCE OF THE PROGRAM IS WITH YOU.
    SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF ALL
    NECESSARY SERVICING, REPAIR OR CORRECTION.

17. **Limitation of Liability.**

    IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN
    WRITING WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MODIFIES
    AND/OR CONVEYS THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR
    DAMAGES, INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL
    DAMAGES ARISING OUT OF THE USE OR INABILITY TO USE THE PROGRAM
    (INCLUDING BUT NOT LIMITED TO LOSS OF DATA OR DATA BEING RENDERED
    INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD PARTIES OR A FAILURE
    OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS), EVEN IF SUCH
    HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF
    SUCH DAMAGES.

18. **Interpretation of Sections 15 and 16.**

    If the disclaimer of warranty and limitation of liability provided
    above cannot be given local legal effect according to their terms,
    reviewing courts shall apply local law that most closely
    approximates an absolute waiver of all civil liability in connection
    with the Program, unless a warranty or assumption of liability
    accompanies a copy of the Program in return for a fee.

END OF TERMS AND CONDITIONS {#end-of-terms-and-conditions .heading}
---------------------------

How to Apply These Terms to Your New Programs {#how-to-apply-these-terms-to-your-new-programs .heading}
---------------------------------------------

If you develop a new program, and you want it to be of the greatest
possible use to the public, the best way to achieve this is to make it
free software which everyone can redistribute and change under these
terms.

To do so, attach the following notices to the program. It is safest to
attach them to the start of each source file to most effectively state
the exclusion of warranty; and each file should have at least the
“copyright” line and a pointer to where the full notice is found.

+--------------------------------------+--------------------------------------+
|                                      | ``` {.smallexample}                  |
|                                      | one line to give the program's name  |
|                                      | and a brief idea of what it does.    |
|                                      | Copyright (C) year name of author    |
|                                      |                                      |
|                                      | This program is free software: you c |
|                                      | an redistribute it and/or modify     |
|                                      | it under the terms of the GNU Genera |
|                                      | l Public License as published by     |
|                                      | the Free Software Foundation, either |
|                                      |  version 3 of the License, or (at    |
|                                      | your option) any later version.      |
|                                      |                                      |
|                                      | This program is distributed in the h |
|                                      | ope that it will be useful, but      |
|                                      | WITHOUT ANY WARRANTY; without even t |
|                                      | he implied warranty of               |
|                                      | MERCHANTABILITY or FITNESS FOR A PAR |
|                                      | TICULAR PURPOSE.  See the GNU        |
|                                      | General Public License for more deta |
|                                      | ils.                                 |
|                                      |                                      |
|                                      | You should have received a copy of t |
|                                      | he GNU General Public License        |
|                                      | along with this program.  If not, se |
|                                      | e http://www.gnu.org/licenses/.      |
|                                      | ```                                  |
+--------------------------------------+--------------------------------------+

Also add information on how to contact you by electronic and paper mail.

If the program does terminal interaction, make it output a short notice
like this when it starts in an interactive mode:

+--------------------------------------+--------------------------------------+
|                                      | ``` {.smallexample}                  |
|                                      | program Copyright (C) year name of a |
|                                      | uthor                                |
|                                      | This program comes with ABSOLUTELY N |
|                                      | O WARRANTY;                          |
|                                      | for details type ‘show w’.  This is  |
|                                      | free software,                       |
|                                      | and you are welcome to redistribute  |
|                                      | it under                             |
|                                      | certain conditions; type ‘show c’ fo |
|                                      | r details.                           |
|                                      | ```                                  |
+--------------------------------------+--------------------------------------+

The hypothetical commands ‘show w’ and ‘show c’ should show the
appropriate parts of the General Public License. Of course, your
program’s commands might be different; for a GUI interface, you would
use an “about box”.

You should also get your employer (if you work as a programmer) or
school, if any, to sign a “copyright disclaimer” for the program, if
necessary. For more information on this, and how to apply and follow the
GNU GPL, see <http://www.gnu.org/licenses/>.

The GNU General Public License does not permit incorporating your
program into proprietary programs. If your program is a subroutine
library, you may consider 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. But first,
please read <http://www.gnu.org/philosophy/why-not-lgpl.html>.

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