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/****************************************************************************
**
** Copyright (C) 2013 Digia Plc and/or its subsidiary(-ies).
** Contact: http://www.qt-project.org/legal
**
** This file is part of the documentation of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:FDL$
** Commercial License Usage
** Licensees holding valid commercial Qt licenses may use this file in
** accordance with the commercial license agreement provided with the
** Software or, alternatively, in accordance with the terms contained in
** a written agreement between you and Digia. For licensing terms and
** conditions see http://qt.digia.com/licensing. For further information
** use the contact form at http://qt.digia.com/contact-us.
**
** GNU Free Documentation License Usage
** Alternatively, this file may be used under the terms of the GNU Free
** Documentation License version 1.3 as published by the Free Software
** Foundation and appearing in the file included in the packaging of
** this file. Please review the following information to ensure
** the GNU Free Documentation License version 1.3 requirements
** will be met: http://www.gnu.org/copyleft/fdl.html.
** $QT_END_LICENSE$
**
****************************************************************************/
/*!
\page ipc.html
\title Inter-Process Communication in Qt
\brief Inter-Process communication in Qt applications.
\ingroup technology-apis
\ingroup qt-basic-concepts
\ingroup qt-network
Qt provides several ways to implement Inter-Process Communication
(IPC) in Qt applications.
\section1 TCP/IP
The cross-platform \l{QtNetwork} module provides classes that make
network programming portable and easy. It offers high-level
classes (e.g., QNetworkAccessManager, QFtp) that communicate using
specific application-level protocols, and lower-level classes
(e.g., QTcpSocket, QTcpServer, QSslSocket) for implementing
protocols.
\section1 Shared Memory
The cross-platform shared memory class, QSharedMemory, provides
access to the operating system's shared memory implementation.
It allows safe access to shared memory segments by multiple threads
and processes. Additionally, QSystemSemaphore can be used to control
access to resources shared by the system, as well as to communicate
between processes.
\section1 D-Bus
The \l{QtDBus} module is a Unix-only library you can use to
implement IPC using the D-Bus protocol. It extends Qt's
\l{signalsandslots.html} {Signals and Slots} mechanism to the IPC
level, allowing a signal emitted by one process to be connected to
a slot in another process. This \l {D-Bus} page has detailed
information on how to use the \l{QtDBus} module.
\section1 Qt COmmunications Protocol (QCOP)
The QCopChannel class implements a protocol for transferring messages
between client processes across named channels. QCopChannel is
only available in \l{Qt for Embedded Linux}. Like the \l{QtDBus}
module, QCOP extends Qt's \l{Signals and Slots} mechanism to the
IPC level, allowing a signal emitted by one process to be
connected to a slot in another process, but unlike QtDBus, QCOP
does not depend on a third party library.
*/
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