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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 (qt-info@nokia.com) |
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7 ** This file is part of the documentation of the Qt Toolkit. |
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9 ** $QT_BEGIN_LICENSE:LGPL$ |
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14 ** this package. |
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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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24 ** In addition, as a special exception, Nokia gives you certain additional |
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37 ** |
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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 */ |