doc/src/frameworks-technologies/ipc.qdoc
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/****************************************************************************
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**
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** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
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** All rights reserved.
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** Contact: Nokia Corporation (qt-info@nokia.com)
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**
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** This file is part of the documentation of the Qt Toolkit.
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**
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** $QT_BEGIN_LICENSE:LGPL$
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** No Commercial Usage
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** This file contains pre-release code and may not be distributed.
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** You may use this file in accordance with the terms and conditions
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** contained in the Technology Preview License Agreement accompanying
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** this package.
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**
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** GNU Lesser General Public License Usage
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** Alternatively, this file may be used under the terms of the GNU Lesser
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** General Public License version 2.1 as published by the Free Software
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** Foundation and appearing in the file LICENSE.LGPL included in the
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** packaging of this file.  Please review the following information to
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** ensure the GNU Lesser General Public License version 2.1 requirements
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** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
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**
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** In addition, as a special exception, Nokia gives you certain additional
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** rights.  These rights are described in the Nokia Qt LGPL Exception
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** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
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**
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** If you have questions regarding the use of this file, please contact
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** Nokia at qt-info@nokia.com.
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**
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**
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**
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**
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**
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**
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**
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**
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** $QT_END_LICENSE$
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**
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****************************************************************************/
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/*!
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    \page ipc.html
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    \title Inter-Process Communication in Qt
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    \brief Inter-Process communication in Qt applications.
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    \ingroup frameworks-technologies
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    Qt provides several ways to implement Inter-Process Communication
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    (IPC) in Qt applications.
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    \section1 TCP/IP
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    The cross-platform \l{QtNetwork} module provides classes that make
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    network programming portable and easy. It offers high-level
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    classes (e.g., QNetworkAccessManager, QFtp) that communicate using
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    specific application-level protocols, and lower-level classes
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    (e.g., QTcpSocket, QTcpServer, QSslSocket) for implementing
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    protocols.
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    \section1 Shared Memory
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    The cross-platform shared memory class, QSharedMemory, provides
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    access to the operating system's shared memory implementation.
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    It allows safe access to shared memory segments by multiple threads
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    and processes. Additionally, QSystemSemaphore can be used to control
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    access to resources shared by the system, as well as to communicate
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    between processes.
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    \section1 D-Bus
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    The \l{QtDBus} module is a Unix-only library
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    you can use to implement IPC using the D-Bus protocol. It extends
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    Qt's \l{signalsandslots.html} {Signals and Slots} mechanism to the
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    IPC level, allowing a signal emitted by one process to be
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    connected to a slot in another process. This \l {Introduction to
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    D-Bus} page has detailed information on how to use the \l{QtDBus}
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    module.
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    \section1 Qt COmmunications Protocol (QCOP)
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    The QCopChannel class implements a protocol for transferring messages
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    between client processes across named channels. QCopChannel is
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    only available in \l{Qt for Embedded Linux}. Like the \l{QtDBus}
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    module, QCOP extends Qt's \l{Signals and Slots} mechanism to the
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    IPC level, allowing a signal emitted by one process to be
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    connected to a slot in another process, but unlike QtDBus, QCOP
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    does not depend on a third party library.
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*/