1 | /****************************************************************************
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2 | **
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3 | ** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
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4 | ** All rights reserved.
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5 | ** Contact: Nokia Corporation ([email protected])
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6 | **
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7 | ** This file is part of the documentation of the Qt Toolkit.
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8 | **
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9 | ** $QT_BEGIN_LICENSE:LGPL$
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10 | ** Commercial Usage
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11 | ** Licensees holding valid Qt Commercial licenses may use this file in
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12 | ** accordance with the Qt Commercial License Agreement provided with the
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13 | ** Software or, alternatively, in accordance with the terms contained in
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14 | ** a written agreement between you and Nokia.
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15 | **
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16 | ** GNU Lesser General Public License Usage
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17 | ** Alternatively, this file may be used under the terms of the GNU Lesser
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18 | ** General Public License version 2.1 as published by the Free Software
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19 | ** Foundation and appearing in the file LICENSE.LGPL included in the
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20 | ** packaging of this file. Please review the following information to
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21 | ** ensure the GNU Lesser General Public License version 2.1 requirements
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22 | ** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
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23 | **
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24 | ** In addition, as a special exception, Nokia gives you certain additional
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25 | ** rights. These rights are described in the Nokia Qt LGPL Exception
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26 | ** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
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27 | **
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28 | ** GNU General Public License Usage
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29 | ** Alternatively, this file may be used under the terms of the GNU
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30 | ** General Public License version 3.0 as published by the Free Software
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31 | ** Foundation and appearing in the file LICENSE.GPL included in the
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32 | ** packaging of this file. Please review the following information to
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33 | ** ensure the GNU General Public License version 3.0 requirements will be
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34 | ** met: http://www.gnu.org/copyleft/gpl.html.
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35 | **
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36 | ** If you have questions regarding the use of this file, please contact
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37 | ** Nokia at [email protected].
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38 | ** $QT_END_LICENSE$
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39 | **
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40 | ****************************************************************************/
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41 |
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42 | /*!
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43 | \page ipc.html
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44 | \title Inter-Process Communication in Qt
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45 | \brief Inter-Process communication in Qt applications.
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46 |
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47 | \ingroup frameworks-technologies
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48 |
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49 | Qt provides several ways to implement Inter-Process Communication
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50 | (IPC) in Qt applications.
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51 |
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52 | \section1 TCP/IP
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53 |
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54 | The cross-platform \l{QtNetwork} module provides classes that make
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55 | network programming portable and easy. It offers high-level
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56 | classes (e.g., QNetworkAccessManager, QFtp) that communicate using
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57 | specific application-level protocols, and lower-level classes
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58 | (e.g., QTcpSocket, QTcpServer, QSslSocket) for implementing
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59 | protocols.
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60 |
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61 | \section1 Shared Memory
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62 |
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63 | The cross-platform shared memory class, QSharedMemory, provides
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64 | access to the operating system's shared memory implementation.
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65 | It allows safe access to shared memory segments by multiple threads
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66 | and processes. Additionally, QSystemSemaphore can be used to control
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67 | access to resources shared by the system, as well as to communicate
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68 | between processes.
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69 |
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70 | \section1 D-Bus
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71 |
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72 | The \l{QtDBus} module is a Unix-only library
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73 | you can use to implement IPC using the D-Bus protocol. It extends
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74 | Qt's \l{signalsandslots.html} {Signals and Slots} mechanism to the
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75 | IPC level, allowing a signal emitted by one process to be
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76 | connected to a slot in another process. This \l {Introduction to
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77 | D-Bus} page has detailed information on how to use the \l{QtDBus}
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78 | module.
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79 |
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80 | \section1 Qt COmmunications Protocol (QCOP)
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81 |
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82 | The QCopChannel class implements a protocol for transferring messages
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83 | between client processes across named channels. QCopChannel is
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84 | only available in \l{Qt for Embedded Linux}. Like the \l{QtDBus}
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85 | module, QCOP extends Qt's \l{Signals and Slots} mechanism to the
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86 | IPC level, allowing a signal emitted by one process to be
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87 | connected to a slot in another process, but unlike QtDBus, QCOP
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88 | does not depend on a third party library.
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89 | */
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