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/****************************************************************************
**
** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
** Contact: Nokia Corporation (qt-info@nokia.com)
**
** This file is part of the documentation of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:LGPL$
** No Commercial Usage
** This file contains pre-release code and may not be distributed.
** You may use this file in accordance with the terms and conditions
** contained in the either Technology Preview License Agreement or the
** Beta Release License Agreement.
**
** 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, Nokia gives you certain
** additional rights. These rights are described in the Nokia Qt LGPL
** Exception version 1.0, 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.
**
** If you are unsure which license is appropriate for your use, please
** contact the sales department at http://www.qtsoftware.com/contact.
** $QT_END_LICENSE$
**
****************************************************************************/
/*!
\group ipc
\title Inter-Process Communication in Qt
\ingroup groups
\ingroup architecture
\brief Inter-Process communication in Qt applications.
Qt provides several ways to implement Inter-Process Communication
(IPC) in Qt applications.
\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 TCP/IP
The cross-platform \l{QtNetwork} module
provides classes that make network programming portable and
easy. It offers high-level classes (e.g., QHttp, 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 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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