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/****************************************************************************
**
** Copyright (C) 2012 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.
**
** $QT_BEGIN_LICENSE:LGPL$
** 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 Lesser General Public License Usage
** Alternatively, this file may be used under the terms of the GNU Lesser
** General Public License version 2.1 as published by the Free Software
** Foundation and appearing in the file LICENSE.LGPL included in the
** packaging of this file. Please review the following information to
** ensure the GNU Lesser General Public License version 2.1 requirements
** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
**
** In addition, as a special exception, Digia gives you certain additional
** rights. These rights are described in the Digia Qt LGPL Exception
** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
**
** GNU General Public License Usage
** Alternatively, this file may be used under the terms of the GNU
** General Public License version 3.0 as published by the Free Software
** Foundation and appearing in the file LICENSE.GPL included in the
** packaging of this file. Please review the following information to
** ensure the GNU General Public License version 3.0 requirements will be
** met: http://www.gnu.org/copyleft/gpl.html.
**
**
** $QT_END_LICENSE$
**
****************************************************************************/
/*!
\page ipc.html
\title Inter-Process Communication in Qt
\brief Inter-Process communication in Qt applications.
\ingroup frameworks-technologies
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 {Introduction to
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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