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# Qt Documentation

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  * Darwin

# Darwin

[Project Homepage](http://www.opensource.apple.com/)

    
    
    APPLE PUBLIC SOURCE LICENSE Version 2.0 -  August 6, 2003
    
    Please read this License carefully before downloading this software.  By
    downloading or using this software, you are agreeing to be bound by the terms of
    this License.  If you do not or cannot agree to the terms of this License,
    please do not download or use the software.
    
    Apple Note:  In January 2007, Apple changed its corporate name from "Apple
    Computer, Inc." to "Apple Inc."  This change has been reflected below and
    copyright years updated, but no other changes have been made to the APSL 2.0.
    
    1.      General; Definitions.  This License applies to any program or other work
    which Apple Inc. ("Apple") makes publicly available and which contains a notice
    placed by Apple identifying such program or work as "Original Code" and stating
    that it is subject to the terms of this Apple Public Source License version 2.0
    ("License").  As used in this License:
    
    1.1      "Applicable Patent Rights" mean:  (a) in the case where Apple is the
    grantor of rights, (i) claims of patents that are now or hereafter acquired,
    owned by or assigned to Apple and (ii) that cover subject matter contained in
    the Original Code, but only to the extent necessary to use, reproduce and/or
    distribute the Original Code without infringement; and (b) in the case where You
    are the grantor of rights, (i) claims of patents that are now or hereafter
    acquired, owned by or assigned to You and (ii) that cover subject matter in Your
    Modifications, taken alone or in combination with Original Code.
    
    1.2     "Contributor" means any person or entity that creates or contributes to the
    creation of Modifications.
    
    1.3      "Covered Code" means the Original Code, Modifications, the combination of
    Original Code and any Modifications, and/or any respective portions thereof.
    
    1.4     "Externally Deploy" means: (a) to sublicense, distribute or otherwise make
    Covered Code available, directly or indirectly, to anyone other than You; and/or
    (b) to use Covered Code, alone or as part of a Larger Work, in any way to
    provide a service, including but not limited to delivery of content, through
    electronic communication with a client other than You.
    
    1.5     "Larger Work" means a work which combines Covered Code or portions thereof
    with code not governed by the terms of this License.
    
    1.6     "Modifications" mean any addition to, deletion from, and/or change to, the
    substance and/or structure of the Original Code, any previous Modifications, the
    combination of Original Code and any previous Modifications, and/or any
    respective portions thereof.  When code is released as a series of files, a
    Modification is:  (a) any addition to or deletion from the contents of a file
    containing Covered Code; and/or (b) any new file or other representation of
    computer program statements that contains any part of Covered Code.
    
    1.7     "Original Code" means (a) the Source Code of a program or other work as
    originally made available by Apple under this License, including the Source Code
    of any updates or upgrades to such programs or works made available by Apple
    under this License, and that has been expressly identified by Apple as such in
    the header file(s) of such work; and (b) the object code compiled from such
    Source Code and originally made available by Apple under this License
    
    1.8     "Source Code" means the human readable form of a program or other work that
    is suitable for making modifications to it, including all modules it contains,
    plus any associated interface definition files, scripts used to control
    compilation and installation of an executable (object code).
    
    1.9     "You" or "Your" means an individual or a legal entity exercising rights
    under this License.  For legal entities, "You" or "Your" includes any entity
    which controls, is controlled by, or is under common control with, You, where
    "control" means (a) the power, direct or indirect, to cause the direction or
    management of such entity, whether by contract or otherwise, or (b) ownership of
    fifty percent (50%) or more of the outstanding shares or beneficial ownership of
    such entity.
    
    2.      Permitted Uses; Conditions &amp; Restrictions.   Subject to the terms and
    conditions of this License, Apple hereby grants You, effective on the date You
    accept this License and download the Original Code, a world-wide, royalty-free,
    non-exclusive license, to the extent of Apple's Applicable Patent Rights and
    copyrights covering the Original Code, to do the following:
    
    2.1     Unmodified Code.  You may use, reproduce, display, perform, internally
    distribute within Your organization, and Externally Deploy verbatim, unmodified
    copies of the Original Code, for commercial or non-commercial purposes, provided
    that in each instance:
    
    (a)     You must retain and reproduce in all copies of Original Code the copyright
    and other proprietary notices and disclaimers of Apple as they appear in the
    Original Code, and keep intact all notices in the Original Code that refer to
    this License; and
    
    (b)     You must include a copy of this License with every copy of Source Code of
    Covered Code and documentation You distribute or Externally Deploy, and You may
    not offer or impose any terms on such Source Code that alter or restrict this
    License or the recipients' rights hereunder, except as permitted under Section
    6.
    
    2.2     Modified Code.  You may modify Covered Code and use, reproduce, display,
    perform, internally distribute within Your organization, and Externally Deploy
    Your Modifications and Covered Code, for commercial or non-commercial purposes,
    provided that in each instance You also meet all of these conditions:
    
    (a)     You must satisfy all the conditions of Section 2.1 with respect to the
    Source Code of the Covered Code;
    
    (b)     You must duplicate, to the extent it does not already exist, the notice in
    Exhibit A in each file of the Source Code of all Your Modifications, and cause
    the modified files to carry prominent notices stating that You changed the files
    and the date of any change; and
    
    (c)     If You Externally Deploy Your Modifications, You must make Source Code of
    all Your Externally Deployed Modifications either available to those to whom You
    have Externally Deployed Your Modifications, or publicly available.  Source Code
    of Your Externally Deployed Modifications must be released under the terms set
    forth in this License, including the license grants set forth in Section 3
    below, for as long as you Externally Deploy the Covered Code or twelve (12)
    months from the date of initial External Deployment, whichever is longer. You
    should preferably distribute the Source Code of Your Externally Deployed
    Modifications electronically (e.g. download from a web site).
    
    2.3     Distribution of Executable Versions.  In addition, if You Externally Deploy
    Covered Code (Original Code and/or Modifications) in object code, executable
    form only, You must include a prominent notice, in the code itself as well as in
    related documentation, stating that Source Code of the Covered Code is available
    under the terms of this License with information on how and where to obtain such
    Source Code.
    
    2.4     Third Party Rights.  You expressly acknowledge and agree that although
    Apple and each Contributor grants the licenses to their respective portions of
    the Covered Code set forth herein, no assurances are provided by Apple or any
    Contributor that the Covered Code does not infringe the patent or other
    intellectual property rights of any other entity. Apple and each Contributor
    disclaim any liability to You for claims brought by any other entity based on
    infringement of intellectual property rights or otherwise. As a condition to
    exercising the rights and licenses granted hereunder, You hereby assume sole
    responsibility to secure any other intellectual property rights needed, if any.
    For example, if a third party patent license is required to allow You to
    distribute the Covered Code, it is Your responsibility to acquire that license
    before distributing the Covered Code.
    
    3.      Your Grants.  In consideration of, and as a condition to, the licenses
    granted to You under this License, You hereby grant to any person or entity
    receiving or distributing Covered Code under this License a non-exclusive,
    royalty-free, perpetual, irrevocable license, under Your Applicable Patent
    Rights and other intellectual property rights (other than patent) owned or
    controlled by You, to use, reproduce, display, perform, modify, sublicense,
    distribute and Externally Deploy Your Modifications of the same scope and extent
    as Apple's licenses under Sections 2.1 and 2.2 above.
    
    4.      Larger Works.  You may create a Larger Work by combining Covered Code with
    other code not governed by the terms of this License and distribute the Larger
    Work as a single product.  In each such instance, You must make sure the
    requirements of this License are fulfilled for the Covered Code or any portion
    thereof.
    
    5.      Limitations on Patent License.   Except as expressly stated in Section 2, no
    other patent rights, express or implied, are granted by Apple herein.
    Modifications and/or Larger Works may require additional patent licenses from
    Apple which Apple may grant in its sole discretion.
    
    6.      Additional Terms.  You may choose to offer, and to charge a fee for,
    warranty, support, indemnity or liability obligations and/or other rights
    consistent with the scope of the license granted herein ("Additional Terms") to
    one or more recipients of Covered Code. However, You may do so only on Your own
    behalf and as Your sole responsibility, and not on behalf of Apple or any
    Contributor. You must obtain the recipient's agreement that any such Additional
    Terms are offered by You alone, and You hereby agree to indemnify, defend and
    hold Apple and every Contributor harmless for any liability incurred by or
    claims asserted against Apple or such Contributor by reason of any such
    Additional Terms.
    
    7.      Versions of the License.  Apple may publish revised and/or new versions of
    this License from time to time.  Each version will be given a distinguishing
    version number.  Once Original Code has been published under a particular
    version of this License, You may continue to use it under the terms of that
    version. You may also choose to use such Original Code under the terms of any
    subsequent version of this License published by Apple.  No one other than Apple
    has the right to modify the terms applicable to Covered Code created under this
    License.
    
    8.      NO WARRANTY OR SUPPORT.  The Covered Code may contain in whole or in part
    pre-release, untested, or not fully tested works.  The Covered Code may contain
    errors that could cause failures or loss of data, and may be incomplete or
    contain inaccuracies.  You expressly acknowledge and agree that use of the
    Covered Code, or any portion thereof, is at Your sole and entire risk.  THE
    COVERED CODE IS PROVIDED "AS IS" AND WITHOUT WARRANTY, UPGRADES OR SUPPORT OF
    ANY KIND AND APPLE AND APPLE'S LICENSOR(S) (COLLECTIVELY REFERRED TO AS "APPLE"
    FOR THE PURPOSES OF SECTIONS 8 AND 9) AND ALL CONTRIBUTORS EXPRESSLY DISCLAIM
    ALL WARRANTIES AND/OR CONDITIONS, EXPRESS OR IMPLIED, INCLUDING, BUT NOT LIMITED
    TO, THE IMPLIED WARRANTIES AND/OR CONDITIONS OF MERCHANTABILITY, OF SATISFACTORY
    QUALITY, OF FITNESS FOR A PARTICULAR PURPOSE, OF ACCURACY, OF QUIET ENJOYMENT,
    AND NONINFRINGEMENT OF THIRD PARTY RIGHTS.  APPLE AND EACH CONTRIBUTOR DOES NOT
    WARRANT AGAINST INTERFERENCE WITH YOUR ENJOYMENT OF THE COVERED CODE, THAT THE
    FUNCTIONS CONTAINED IN THE COVERED CODE WILL MEET YOUR REQUIREMENTS, THAT THE
    OPERATION OF THE COVERED CODE WILL BE UNINTERRUPTED OR ERROR-FREE, OR THAT
    DEFECTS IN THE COVERED CODE WILL BE CORRECTED.  NO ORAL OR WRITTEN INFORMATION
    OR ADVICE GIVEN BY APPLE, AN APPLE AUTHORIZED REPRESENTATIVE OR ANY CONTRIBUTOR
    SHALL CREATE A WARRANTY.  You acknowledge that the Covered Code is not intended
    for use in the operation of nuclear facilities, aircraft navigation,
    communication systems, or air traffic control machines in which case the failure
    of the Covered Code could lead to death, personal injury, or severe physical or
    environmental damage.
    
    9.      LIMITATION OF LIABILITY. TO THE EXTENT NOT PROHIBITED BY LAW, IN NO EVENT
    SHALL APPLE OR ANY CONTRIBUTOR BE LIABLE FOR ANY INCIDENTAL, SPECIAL, INDIRECT
    OR CONSEQUENTIAL DAMAGES ARISING OUT OF OR RELATING TO THIS LICENSE OR YOUR USE
    OR INABILITY TO USE THE COVERED CODE, OR ANY PORTION THEREOF, WHETHER UNDER A
    THEORY OF CONTRACT, WARRANTY, TORT (INCLUDING NEGLIGENCE), PRODUCTS LIABILITY OR
    OTHERWISE, EVEN IF APPLE OR SUCH CONTRIBUTOR HAS BEEN ADVISED OF THE POSSIBILITY
    OF SUCH DAMAGES AND NOTWITHSTANDING THE FAILURE OF ESSENTIAL PURPOSE OF ANY
    REMEDY. SOME JURISDICTIONS DO NOT ALLOW THE LIMITATION OF LIABILITY OF
    INCIDENTAL OR CONSEQUENTIAL DAMAGES, SO THIS LIMITATION MAY NOT APPLY TO YOU. In
    no event shall Apple's total liability to You for all damages (other than as may
    be required by applicable law) under this License exceed the amount of fifty
    dollars ($50.00).
    
    10.     Trademarks.  This License does not grant any rights to use the trademarks
    or trade names  "Apple", "Mac", "Mac OS", "QuickTime", "QuickTime Streaming
    Server" or any other trademarks, service marks, logos or trade names belonging
    to Apple (collectively "Apple Marks") or to any trademark, service mark, logo or
    trade name belonging to any Contributor.  You agree not to use any Apple Marks
    in or as part of the name of products derived from the Original Code or to
    endorse or promote products derived from the Original Code other than as
    expressly permitted by and in strict compliance at all times with Apple's third
    party trademark usage guidelines which are posted at
    http://www.apple.com/legal/guidelinesfor3rdparties.html.
    
    11.     Ownership. Subject to the licenses granted under this License, each
    Contributor retains all rights, title and interest in and to any Modifications
    made by such Contributor.  Apple retains all rights, title and interest in and
    to the Original Code and any Modifications made by or on behalf of Apple ("Apple
    Modifications"), and such Apple Modifications will not be automatically subject
    to this License.  Apple may, at its sole discretion, choose to license such
    Apple Modifications under this License, or on different terms from those
    contained in this License or may choose not to license them at all.
    
    12.     Termination.
    
    12.1    Termination.  This License and the rights granted hereunder will
    terminate:
    
    (a)     automatically without notice from Apple if You fail to comply with any
    term(s) of this License and fail to cure such breach within 30 days of becoming
    aware of such breach; (b)       immediately in the event of the circumstances
    described in Section 13.5(b); or (c)    automatically without notice from Apple if
    You, at any time during the term of this License, commence an action for patent
    infringement against Apple; provided that Apple did not first commence an action
    for patent infringement against You in that instance.
    
    12.2    Effect of Termination.  Upon termination, You agree to immediately stop
    any further use, reproduction, modification, sublicensing and distribution of
    the Covered Code.  All sublicenses to the Covered Code which have been properly
    granted prior to termination shall survive any termination of this License.
    Provisions which, by their nature, should remain in effect beyond the
    termination of this License shall survive, including but not limited to Sections
    3, 5, 8, 9, 10, 11, 12.2 and 13.  No party will be liable to any other for
    compensation, indemnity or damages of any sort solely as a result of terminating
    this License in accordance with its terms, and termination of this License will
    be without prejudice to any other right or remedy of any party.
    
    13.     Miscellaneous.
    
    13.1    Government End Users.   The Covered Code is a "commercial item" as defined
    in FAR 2.101.  Government software and technical data rights in the Covered Code
    include only those rights customarily provided to the public as defined in this
    License. This customary commercial license in technical data and software is
    provided in accordance with FAR 12.211 (Technical Data) and 12.212 (Computer
    Software) and, for Department of Defense purchases, DFAR 252.227-7015 (Technical
    Data -- Commercial Items) and 227.7202-3 (Rights in Commercial Computer Software
    or Computer Software Documentation).  Accordingly, all U.S. Government End Users
    acquire Covered Code with only those rights set forth herein.
    
    13.2    Relationship of Parties.  This License will not be construed as creating
    an agency, partnership, joint venture or any other form of legal association
    between or among You, Apple or any Contributor, and You will not represent to
    the contrary, whether expressly, by implication, appearance or otherwise.
    
    13.3    Independent Development.   Nothing in this License will impair Apple's
    right to acquire, license, develop, have others develop for it, market and/or
    distribute technology or products that perform the same or similar functions as,
    or otherwise compete with, Modifications, Larger Works, technology or products
    that You may develop, produce, market or distribute.
    
    13.4    Waiver; Construction.  Failure by Apple or any Contributor to enforce any
    provision of this License will not be deemed a waiver of future enforcement of
    that or any other provision.  Any law or regulation which provides that the
    language of a contract shall be construed against the drafter will not apply to
    this License.
    
    13.5    Severability.  (a) If for any reason a court of competent jurisdiction
    finds any provision of this License, or portion thereof, to be unenforceable,
    that provision of the License will be enforced to the maximum extent permissible
    so as to effect the economic benefits and intent of the parties, and the
    remainder of this License will continue in full force and effect.  (b)
    Notwithstanding the foregoing, if applicable law prohibits or restricts You from
    fully and/or specifically complying with Sections 2 and/or 3 or prevents the
    enforceability of either of those Sections, this License will immediately
    terminate and You must immediately discontinue any use of the Covered Code and
    destroy all copies of it that are in your possession or control.
    
    13.6    Dispute Resolution.  Any litigation or other dispute resolution between
    You and Apple relating to this License shall take place in the Northern District
    of California, and You and Apple hereby consent to the personal jurisdiction of,
    and venue in, the state and federal courts within that District with respect to
    this License. The application of the United Nations Convention on Contracts for
    the International Sale of Goods is expressly excluded.
    
    13.7    Entire Agreement; Governing Law.  This License constitutes the entire
    agreement between the parties with respect to the subject matter hereof.  This
    License shall be governed by the laws of the United States and the State of
    California, except that body of California law concerning conflicts of law.
    
    Where You are located in the province of Quebec, Canada, the following clause
    applies:  The parties hereby confirm that they have requested that this License
    and all related documents be drafted in English.  Les parties ont exigé que le
    présent contrat et tous les documents connexes soient rédigés en anglais.
    
    EXHIBIT A.
    
    "Portions Copyright (c) 1999-2007 Apple Inc.  All Rights Reserved.
    
    This file contains Original Code and/or Modifications of Original Code as
    defined in and that are subject to the Apple Public Source License Version 2.0
    (the 'License').  You may not use this file except in compliance with the
    License.  Please obtain a copy of the License at
    http://www.opensource.apple.com/apsl/ and read it before using this file.
    
    The Original Code and all software distributed under the License are distributed
    on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESS OR IMPLIED,
    AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, INCLUDING WITHOUT LIMITATION,
    ANY WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, QUIET
    ENJOYMENT OR NON-INFRINGEMENT.  Please see the License for the specific language
    governing rights and limitations under the License."

© 2020 The Qt Company Ltd. Documentation contributions included herein are the
copyrights of their respective owners. The documentation provided herein is
licensed under the terms of the [GNU Free Documentation License version
1.3](https://www.gnu.org/licenses/fdl.html) as published by the Free Software
Foundation. Qt and respective logos are trademarks of The Qt Company Ltd. in
Finland and/or other countries worldwide. All other trademarks are property of
their respective owners.

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