LICENSE.txt

                    GNU GENERAL PUBLIC LICENSE
                       Version 3, 29 June 2007

 Copyright (C) 2007 Free Software Foundation, Inc. <https://fsf.org/>
 Everyone is permitted to copy and distribute verbatim 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 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
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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

  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".  "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.

  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 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.

  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.

  5. 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:

    a) The work must carry prominent notices stating that you modified
    it, and giving a relevant date.

    b) 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".

    c) 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.

    d) 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.

  6. 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:

    a) 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.

    b) 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.

    c) 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.

    d) 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.

    e) 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.

  7. 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:

    a) Disclaiming warranty or limiting liability differently from the
    terms of sections 15 and 16 of this License; or

    b) 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

    c) 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

    d) Limiting the use for publicity purposes of names of licensors or
    authors of the material; or

    e) Declining to grant rights under trademark law for use of some
    trade names, trademarks, or service marks; or

    f) 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.

  8. 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.

  9. 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.

  10. 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.

  11. 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.

  12. 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.

  13. 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.

  14. 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.

  15. 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.

  16. 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.

  17. 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

            How to Apply These Terms to Your New Programs

  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.

    <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 can redistribute it and/or modify
    it under the terms of the GNU General 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 hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program.  If not, see <https://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:

    <program>  Copyright (C) <year>  <name of author>
    This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
    This is free software, and you are welcome to redistribute it
    under certain conditions; type `show c' for 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
<https://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
<https://www.gnu.org/licenses/why-not-lgpl.html>.
                     GNU 通用公共许可证
                      第 3 版，2007 年 6 月 29 日

 版权所有 (C) 2007 自由软件基金会, Inc. <https://fsf.org/>
 允许每个人复制和发布本许可证文档的完整副本，但禁止更改。

                            序言

  GNU 通用公共许可证是一份针对软件及其他类型作品的自由、著佐权（copyleft）许可证。

  大多数软件和其他实用作品的许可证旨在剥夺您分享和更改作品的自由。相反，GNU 通用公共许可证旨在保障您分享和更改程序所有版本的自由——确保它对其所有用户保持自由软件的状态。我们，自由软件基金会，将 GNU 通用公共许可证用于我们的大多数软件；它也适用于任何作者以此方式发布的其他作品。您也可以将其应用于您的程序。

  当我们谈论自由软件时，我们指的是自由，而非价格。我们的通用公共许可证旨在确保您拥有分发自由软件副本的自由（并且如果您愿意，可以为此收费），确保您收到源代码或者可以根据需要获得它，确保您可以更改软件或在新的自由程序中使用其片段，并且确保您知道您可以做这些事情。

  为了保护您的权利，我们需要防止他人否认您的这些权利或要求您放弃这些权利。因此，如果您分发软件的副本，或者如果您修改它，您将承担某些责任：尊重他人自由的责任。

  例如，如果您分发此类程序的副本，无论是免费还是收费，您必须将您获得的相同自由传递给接收者。您必须确保他们也能收到或可以获得源代码。并且您必须向他们展示这些条款，以便他们了解自己的权利。

  使用 GNU GPL 的开发者通过两个步骤来保护您的权利：(1) 声明软件的版权，(2) 向您提供本许可证，授予您合法复制、分发和/或修改它的许可。

  为了开发者和作者的保护，GPL 明确说明对此自由软件不提供担保。为了用户和作者双方的利益，GPL 要求修改版本必须标明已被更改，以免它们的问题被错误地归咎于先前版本的作者。

  某些设备被设计为拒绝用户安装或运行其内部的软件修改版本，尽管制造商可以这样做。这与保护用户更改软件自由的宗旨根本不相容。这种滥用的系统性模式发生在个人使用的产品领域，而这恰恰是最不可接受的地方。因此，我们设计了此版本的 GPL 来禁止此类产品的这种做法。如果此类问题在其他领域大量出现，我们随时准备在 GPL 的未来版本中将此规定扩展到这些领域，以保护用户的自由。

  最后，每个程序都不断受到软件专利的威胁。国家不应允许专利限制通用计算机上软件的开发和使用，但在那些允许的国家，我们希望避免专利应用于自由程序可能使其实际上变成专有软件的特殊危险。为防止这种情况，GPL 确保专利不能用于使程序变得非自由。

  复制、分发和修改的精确条款与条件如下。

                       条款与条件

  0. 定义。

  “本许可证”指 GNU 通用公共许可证第 3 版。

  “版权”也指适用于其他类型作品的类似版权的法律，例如半导体掩模。

  “本程序”指根据本许可证授权的任何可受版权保护的作品。每个被许可方称为“您”。“被许可方”和“接收方”可以是个人或组织。

  “修改”作品指以需要版权许可的方式复制或改编作品的全部或部分内容，而非制作精确副本。所产生的作品称为早期作品的“修改版本”或“基于”早期作品的作品。

  “覆盖的作品”指未被修改的本程序或基于本程序的作品。

  “传播”作品指对其进行的任何行为，若未经许可，将根据适用的版权法使您直接或间接承担侵权责任，但在计算机上执行或修改私有副本除外。传播包括复制、分发（无论是否修改）、向公众提供，以及在有些国家还包括其他活动。

  “传播”作品指使其他方能够制作或接收副本的任何类型的传播。仅通过计算机网络与用户交互而不传输副本，不构成传播。

  交互式用户界面显示“适当的法律声明”的程度是：它包含一个方便且醒目可见的特性，该特性 (1) 显示适当的版权声明，并且 (2) 告诉用户该作品不提供任何担保（除非提供担保），被许可方可以根据本许可证传播该作品，以及如何查看本许可证的副本。如果该界面呈现用户命令或选项列表（例如菜单），列表中的一个突出项即满足此标准。

  1. 源代码。

  作品的“源代码”指对该作品进行修改的首选形式。“目标代码”指作品的任何非源代码形式。

  “标准接口”指或者是公认标准团体定义的官方标准，或者，对于为特定编程语言指定的接口，指在该语言开发者中广泛使用的接口。

  可执行作品的“系统库”包括除作品整体之外的任何内容，该内容 (a) 包含在打包主要组件的常规形式中，但不属于该主要组件的一部分，并且 (b) 仅用于使该作品能与该主要组件一起使用，或用于实现一个标准接口，而该接口的实现以源代码形式公开可用。在此上下文中，“主要组件”指运行可执行作品的特定操作系统（如果有）的主要基本组件（内核、窗口系统等），或用于生成该作品的编译器，或用于运行它的目标代码解释器。

  目标代码形式作品的“相应的源代码”指生成、安装和（对于可执行作品）运行目标代码以及修改作品所需的所有源代码，包括控制这些活动的脚本。然而，它不包括作品的系统库，或执行这些活动时未修改使用的通用工具或普遍可用的自由程序，但那些不是作品的一部分。例如，相应的源代码包括与作品源文件关联的接口定义文件，以及作品专门设计要求的共享库和动态链接子程序的源代码，例如通过它们与作品其他部分之间密切的数据通信或控制流。

  相应的源代码不需要包含用户可以从相应的源代码其他部分自动重新生成的任何内容。

  源代码形式作品的相应的源代码即该作品本身。

  2. 基本许可。

  根据本许可证授予的所有权利在程序的版权期限内授予，并且在满足所述条件的前提下不可撤销。本许可证明确确认您运行未修改程序的无限许可。运行覆盖的作品所产生的输出，仅当根据其内容构成覆盖的作品时，才受本许可证保护。本许可证承认您合理使用或其他版权法规定的等效权利。

  您可以制作、运行和传播您不传播的覆盖的作品，只要您的许可保持有效，没有任何条件限制。您可以将覆盖的作品传播给他人，其唯一目的是让他们专门为您进行修改，或为您提供运行这些作品的设施，前提是您在传播所有您不控制版权的材料时遵守本许可证的条款。那些因此为您制作或运行覆盖的作品的人必须在您的指示和控制下，代表您独家进行，并且条款禁止他们在与您的关系之外制作您版权材料的任何副本。

  在任何其他情况下进行传播，仅允许遵守下述规定的条件。不允许再许可；第 10 条使其成为不必要。

  3. 保护用户法律权利免受反规避法影响。

  任何覆盖的作品均不应被视为根据任何履行 1996 年 12 月 20 日通过的《WIPO 版权条约》第 11 条义务的适用法律，或禁止或限制规避此类措施的其他类似法律构成的有效技术措施的一部分。

  当您传播覆盖的作品时，您放弃任何法律权力以禁止规避技术措施，只要该规避是通过行使本许可证下关于该覆盖作品的权利实现的，并且您否认任何意图限制该作品的操作或修改，以此作为针对作品用户执行您或第三方禁止规避技术措施的法律权利的手段。

  4. 传播完整副本。

  您可以按您收到的方式，以任何媒介传播本程序源代码的完整副本，前提是您必须在每份副本上显著且适当地发布适当的版权声明；保持所有声明本许可证及任何根据第 7 条添加的非许可性条款适用于该代码的通知完整无缺；保持所有关于没有任何担保的通知完整无缺；并向所有接收者随程序一起提供一份本许可证副本。

  您可以对您传播的每份副本收取任何价格或不收费，并且您可以提供收费的支持或担保保护。

  5. 传播修改后的源代码版本。

  您可以基于本程序的作品，或为从本程序产生它而进行的修改，以源代码形式根据第 4 条的条款进行传播，但前提是您还必须满足以下所有条件：

    a) 该作品必须带有显著的通知，声明您修改了它，并给出相关日期。
    b) 该作品必须带有显著的通知，声明其根据本许可证以及根据第 7 条添加的任何条件发布。此要求修改了第 4 条中“保持所有通知完整无缺”的要求。
    c) 您必须将整个作品作为一个整体，根据本许可证许可给任何持有其副本的人。因此，本许可证以及任何适用的第 7 条附加条款将适用于整个作品及其所有部分，无论它们如何打包。本许可证不允许以任何其他方式许可该作品，但如果您单独获得此类许可，本许可证不会使其无效。
    d) 如果该作品具有交互式用户界面，则每个界面必须显示适当的法律声明；但是，如果本程序具有不显示适当法律声明的交互式界面，则您的作品无需使其显示。

  将覆盖的作品与其他独立且独立（就其性质而言不是覆盖作品的扩展）的作品进行编译，并且未与其组合以形成更大的程序，在存储或分发媒介的一个卷上或其中，如果该编译及其产生的版权未被用于限制编译用户超出单个作品所允许的访问或法律权利，则称为“聚合体”。在聚合体中包含覆盖的作品不会导致本许可证适用于聚合体的其他部分。

  6. 传播非源代码形式。

  您可以根据第 4 条和第 5 条的条款，以目标代码形式传播覆盖的作品，前提是您也根据本许可证的条款，以下列方式之一传播机器可读的相应的源代码：

    a) 在物理产品（包括物理分发媒介）中或体现于其中的目标代码，随附固定在通常用于软件交换的耐用物理介质上的相应的源代码。
    b) 在物理产品（包括物理分发媒介）中或体现于其中的目标代码，随附一份书面要约，有效期至少三年，且有效期与您为该产品型号提供备件或客户支持的时间一样长，向持有目标代码的任何人提供 (1) 该产品中受本许可证覆盖的所有软件的相应的源代码副本，在通常用于软件交换的耐用物理介质上，价格不超过您实际执行此源代码传播的合理成本，或 (2) 免费从网络服务器复制相应的源代码的访问权限。
    c) 单独传播目标代码的副本，并附上提供相应的源代码的书面要约副本。此替代方案仅允许偶尔且非商业性地使用，并且仅在您收到带有此类要约的目标代码时（根据第 6 小节 b 款）。
    d) 通过提供从指定地点（免费或收费）访问的方式传播目标代码，并以相同的方式通过相同的地点免费提供对相应的源代码的等效访问。您无需要求接收者随目标代码一起复制相应的源代码。如果复制目标代码的地点是网络服务器，相应的源代码可以位于支持等效复制功能的不同服务器（由您或第三方运营）上，前提是您必须在目标代码旁边提供清晰的指示，说明在哪里可以找到相应的源代码。无论相应的源代码托管在什么服务器上，您仍有义务确保其在需要满足这些要求的期间内保持可用。
    e) 使用点对点传输传播目标代码，前提是您告知其他对等方，根据第 6 小节 d 款，该作品的目标代码和相应的源代码正在免费向公众提供。

  目标代码中可分离的部分，其源代码作为系统库被排除在相应的源代码之外，在传播目标代码作品时无需包含在内。

  “用户产品”指 (1) “消费品”，即通常用于个人、家庭或家居目的的任何有形动产，或 (2) 为并入住宅而设计或销售的任何物品。在确定产品是否为消费品时，有疑问的情况应按照有利于覆盖的范围解决。对于特定用户收到的特定产品，“通常使用”指该类产品的典型或常见用途，无论特定用户的身份或特定用户实际使用、或期望或预期使用产品的方式如何。无论产品是否具有实质性的商业、工业或非消费者用途，产品都是消费品，除非此类用途代表产品的唯一重要使用模式。

  用户产品的“安装信息”指从修改后的相应的源代码在该用户产品中安装和执行覆盖作品的修改版本所需的任何方法、程序、授权密钥或其他信息。该信息必须足以确保修改后的目标代码的持续功能在任何情况下都不会仅仅因为进行了修改而被阻止或干扰。

  如果您在用户产品中、随用户产品一起或专门供其在用户产品中使用的情况下，根据本节传播目标代码作品，并且传播是交易的一部分，在该交易中用户产品的占有和使用权永久或固定期限（无论交易如何定性）转移给接收方，则根据本节传播的相应的源代码必须随附安装信息。但是，如果您或任何第三方都未保留在用户产品上安装修改后的目标代码的能力（例如，作品已安装在 ROM 中），则此要求不适用。

  提供安装信息的要求不包括要求继续为已被接收方修改或安装的作品，或其中已修改或安装了作品的用户产品提供支持服务、担保或更新。当修改本身实质性和不利地影响网络操作或违反网络通信规则和协议时，可能会被拒绝访问网络。

  根据本节传播的相应的源代码和提供的安装信息，必须采用公开文档化的格式（并且其实现以源代码形式公开可用），并且解包、读取或复制时不需要特殊的密码或密钥。

  7. 附加条款。

  “附加许可”是通过对本许可证的一个或多个条件作出例外来补充本许可证条款的条款。适用于整个程序的附加许可应被视为包含在本许可证中，只要它们根据适用法律有效。如果附加许可仅适用于程序的一部分，则该部分可以在这些许可下单独使用，但整个程序仍受本许可证约束，而不考虑附加许可。

  当您传播覆盖的作品的副本时，您可以选择从该副本或其任何部分中移除任何附加许可。（附加许可可能要求在您修改作品时在某些情况下移除它们。）对于您添加到覆盖作品中的材料，如果您拥有或能够授予适当的版权许可，您可以在该材料上放置附加许可。

  尽管有本许可证的任何其他规定，对于您添加到覆盖作品中的材料，您可以（如果该材料的版权持有者授权）用以下条款补充本许可证的条款：

    a) 以不同于本许可证第 15 条和第 16 条的条款声明不承担担保或限制责任；或
    b) 要求在该材料中或在包含它的作品显示的适当法律声明中保留特定的合理法律声明或作者署名；或
    c) 禁止对该材料的来源进行虚假陈述，或要求以合理方式将此类材料的修改版本标记为与原始版本不同；或
    d) 限制将许可方或材料作者的名字用于宣传目的；或
    e) 拒绝为使用某些商号、商标或服务标志授予商标法下的权利；或
    f) 要求任何传播该材料（或其修改版本）的人向许可方和该材料的作者提供赔偿，该传播行为使接收方承担合同责任，以赔偿这些合同责任直接给许可方和作者带来的任何责任。

  所有其他非许可性的附加条款均被视为第 10 条含义内的“进一步限制”。如果您收到的程序或其任何部分包含声明其受本许可证管辖以及一个属于进一步限制的条款的通知，您可以移除该条款。如果许可证文档包含进一步限制但允许根据本许可证进行再许可或传播，您可以向覆盖作品添加受该许可证文档条款管辖的材料，前提是该进一步限制在该再许可或传播后不再存在。

  如果您根据本节向覆盖作品添加条款，您必须在相关的源文件中放置适用于这些文件的附加条款声明，或指明在哪里可以找到适用条款的通知。

  附加条款，无论是许可性的还是非许可性的，可以单独书面许可证的形式陈述，或作为例外情况陈述；上述要求适用于任一方式。

  8. 终止。

  除非本许可证明确允许，否则您不得传播或修改覆盖的作品。任何以其他方式传播或修改它的尝试均属无效，并将自动终止您在本许可证下的权利（包括根据第 11 条第三段授予的任何专利许可）。

  但是，如果您停止所有违反本许可证的行为，那么您从特定版权持有者处获得的许可将 (a) 暂时恢复，除非且直到该版权持有者明确且最终终止您的许可，并且 (b) 永久恢复，如果该版权持有者在您停止后 60 天内未通过合理方式通知您违规行为。

  此外，如果版权持有者通过合理方式通知您违规行为，这是您首次从该版权持有者处收到违反本许可证（针对任何作品）的通知，并且您在收到通知后 30 天内纠正了违规行为，那么您从特定版权持有者处获得的许可将永久恢复。

  本节下您的权利终止不会终止从您处根据本许可证收到副本或权利的方的许可。如果您的权利已被终止且未永久恢复，您没有资格根据第 10 条就相同材料获得新许可。

  9. 持有副本无需接受许可。

  您无需接受本许可证即可接收或运行本程序的副本。仅因使用点对点传输接收副本而发生的覆盖作品的附带传播同样不需要接受许可。然而，除本许可证外，没有任何其他授权授予您传播或修改任何覆盖作品的权限。如果您不接受本许可证，这些行为将侵犯版权。因此，通过修改或传播覆盖的作品，即表明您接受本许可证以进行此类操作。

  10. 下游接收方的自动许可。

  每次您传播覆盖的作品时，接收方自动从原始许可方处获得许可，以运行、修改和传播该作品，但须遵守本许可证。您没有责任强制第三方遵守本许可证。

  “实体交易”是转移组织控制权、或组织全部或实质全部资产、或拆分组织、或合并组织的交易。如果覆盖作品的传播源于实体交易，则该交易的每一方，如果收到作品的副本，也将获得该方的前手利益方根据前款拥有或能够给予的该作品的任何许可，以及从前手利益方获得该作品的相应的源代码的权利（如果前手利益方拥有或可以通过合理努力获得它）。

  您不得对本许可证授予或确认的权利的行使施加任何进一步的限制。例如，您不得对本许可证下授予的权利的行使收取许可费、版税或其他费用，并且您不得提起诉讼（包括诉讼中的交叉索赔或反诉），指控因制作、使用、销售、许诺销售或进口本程序或其任何部分而侵犯任何专利权利要求。

  11. 专利。

  “贡献者”是授权根据本许可证使用本程序或本程序所基于的作品的版权持有者。如此许可的作品称为该贡献者的“贡献者版本”。

  贡献者的“必要专利权利要求”是该贡献者拥有或控制的所有专利权利要求，无论是已经获得还是以后获得的，若以本许可证允许的某种方式制作、使用或销售其贡献者版本将会侵犯这些权利要求，但不包括仅因对贡献者版本进行进一步修改才会被侵犯的权利要求。就本定义而言，“控制”包括以符合本许可证要求的方式授予专利再许可的权利。

  每位贡献者根据该贡献者的必要专利权利要求，向您授予非排他性的、全球范围的、免版税的专利许可，以制作、使用、销售、许诺销售、进口以及以其他方式运行、修改和传播其贡献者版本的内容。

  在以下三段中，“专利许可”指任何明示的协议或承诺，无论其名称如何，不强制执行某项专利（例如专利实施的明示许可或不起诉专利侵权的契约）。“授予”该专利许可给一方指作出不向该方强制执行专利的此类协议或承诺。

  如果您传播覆盖的作品，明知依赖专利许可，而该作品的相应的源代码并非任何人都可以通过公开可用的网络服务器或其他易于访问的方式免费并根据本许可证条款复制，那么您必须 (1) 使相应的源代码如此可用，或 (2) 安排使您自己丧失该专利许可对于此特定作品的利益，或 (3) 以符合本许可证要求的方式安排将专利许可扩展到下游接收方。“明知依赖”指您实际知道，但若没有该专利许可，您在某个国家传播覆盖的作品，或您的接收方在某个国家使用覆盖的作品，将会侵犯您有理由相信在该国有效的一个或多个可识别的专利。

  如果依据或涉及单一交易或安排，您传播，或通过促成传播的方式传播覆盖的作品，并向接收覆盖作品的部分方授予专利许可，授权他们使用、传播、修改或传播该覆盖作品的特定副本，则您授予的专利许可自动扩展到该覆盖作品的所有接收方以及基于它的作品。

  如果专利许可未将其涵盖范围包括在内、禁止行使、或以不行使本许可证特别授予的一项或多项权利为条件，则该专利许可是“歧视性的”。如果您与从事软件分发业务的第三方达成安排，根据该安排您根据传播该作品的活动程度向该第三方付款，并且根据该安排该第三方向任何可能从您处接收覆盖作品的方授予歧视性专利许可 (a) 与您传播的覆盖作品副本（或从这些副本制作的副本）相关，或 (b) 主要针对包含覆盖作品的特定产品或编译，除非您在该日期之前已签订该安排，或该专利许可在该日期之前已被授予（2007 年 3 月 28 日之前）。

  本许可证中的任何内容均不得解释为排除或限制任何根据适用专利法原本可能对您可用的默示许可或其他侵权抗辩。

  12. 不放弃他人的自由。

  如果对您施加的条件（无论是法院命令、协议或其他方式）与本许可证的条件相矛盾，它们也不能免除您遵守本许可证的条件。如果您无法以同时满足您在本许可证下和任何其他相关义务下的责任的方式传播覆盖的作品，那么其后果就是您根本不得传播它。例如，如果您同意要求您向传播对象收取进一步传播的版税的条款，那么同时满足这些条款和本许可证的唯一方法就是完全避免传播本程序。

  13. 与 GNU Affero 通用公共许可证一起使用。

  尽管有本许可证的任何其他规定，您有权将任何覆盖的作品与根据 GNU Affero 通用公共许可证第 3 版许可的作品链接或组合成单个组合作品，并传播产生的作品。本许可证的条款将继续适用于作为覆盖作品的部分，但 GNU Affero 通用公共许可证关于通过网络交互的特殊要求（第 13 条）将适用于该组合本身。

  14. 本许可证的修订版本。

  自由软件基金会可能会不时发布 GNU 通用公共许可证的修订版和/或新版本。此类新版本在精神上类似于当前版本，但可能在细节上有所不同，以解决新的问题或关注点。

  每个版本都有一个不同的版本号。如果本程序指定某个编号的 GNU 通用公共许可证版本“或任何更新的版本”适用于它，您可以选择遵循该编号版本或自由软件基金会发布的任何更新版本的条款和条件。如果本程序未指定 GNU 通用公共许可证的版本号，您可以选择自由软件基金会曾经发布的任何版本。

  如果本程序指定代理可以决定哪些未来版本的 GNU 通用公共许可证可以被使用，则该代理公开接受某个版本的声明永久授权您为该程序选择该版本。

  更新的许可证版本可能会给您额外或不同的许可。然而，选择遵循更新的版本不会对任何作者或版权持有者施加额外的义务。

  15. 免责声明。

  【本程序不提供任何担保，在适用法律允许的最大范围内。除非另有书面声明，版权持有人和/或其他方按“原样”提供本程序，不提供任何形式的明示或默示担保，包括但不限于对适销性和特定用途适用性的默示担保。本程序的全部风险由您承担。如本程序被证明有缺陷，您将承担所有必要的维修、修理或更正的费用。】

  16. 责任限制。

  【在任何情况下，除非适用法律要求或书面同意，任何版权持有人，或任何其他按上述许可修改和/或传播本程序的方，均不对您承担损害赔偿责任，包括任何因使用或无法使用本程序引起的或与之相关的一般性、特殊性、附带性或后果性损害赔偿（包括但不限于数据丢失、数据失真、您或第三方遭受的损失，或本程序无法与其他程序协同操作），即使该持有者或其他方已被告知发生此类损害的可能性也是如此。】

  17. 第 15 条和第 16 条的解释。

  如果上述免责声明和责任限制不能根据其条款在当地法律下产生法律效力，审查法院应适用最接近于完全放弃与本程序相关的所有民事责任的地方法律，除非担保或责任承担伴随着收费的本程序副本。

                    条款与条件结束

            如何将这些条款应用于您的新程序

  如果您开发了一个新程序，并且希望它对公众尽可能有用，实现这一目标的最佳方式是使其成为自由软件，让每个人都可以根据这些条款重新分发和更改它。

  为此，请将以下通知附加到程序上。最安全的做法是将它们附加到每个源文件的开头，以最有效地声明不承担担保；并且每个文件至少应有“版权”行和指向完整通知位置的指针。

    <用一行说明程序的名称及其简要功能。>
    版权所有 (C) <年份>  <作者姓名>

    本程序是自由软件：您可以根据自由软件基金会发布的 GNU 通用公共许可证条款重新分发它和/或修改它，许可证的版本为第 3 版，或（您选择）任何更新的版本。

    本程序的分发是希望它有用，但没有任何担保；甚至没有适销性或特定用途适用性的默示担保。有关更多详细信息，请参阅 GNU 通用公共许可证。

    您应该已经随本程序收到了 GNU 通用公共许可证的副本。如果没有，请参阅 <https://www.gnu.org/licenses/>。

同时添加如何通过电子和纸质邮件联系您的信息。

  如果程序进行终端交互，请使其在交互模式下启动时输出类似以下的简短通知：

    <程序名称> 版权所有 (C) <年份>  <作者姓名>
    本程序绝对不提供任何担保；输入 `show w' 查看详细信息。
    这是自由软件，欢迎您在特定条件下重新分发它；输入 `show c' 查看详细信息。

假设的命令 `show w' 和 `show c' 应显示通用公共许可证的相应部分。当然，您程序的命令可能不同；对于 GUI 界面，您可以使用“关于框”。

  如果必要，您还应让您的雇主（如果您是程序员）或学校（如果有）为程序签署“版权放弃声明”。有关此操作以及如何应用和遵循 GNU GPL 的更多信息，请参阅 <https://www.gnu.org/licenses/>。

  GNU 通用公共许可证不允许将您的程序并入专有程序。如果您的程序是子程序库，您可能会认为允许专有应用程序链接该库更有用。如果这是您想做的，请使用 GNU 宽通用公共许可证（GNU Lesser General Public License）代替本许可证。但首先，请阅读 <https://www.gnu.org/licenses/why-not-lgpl.html>。