/**************************************************************************** ** ** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies). ** All rights reserved. ** 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 Technology Preview License Agreement accompanying ** this package. ** ** 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 1.1, included in the file LGPL_EXCEPTION.txt in this package. ** ** If you have questions regarding the use of this file, please contact ** Nokia at qt-info@nokia.com. ** ** ** ** ** ** ** ** ** $QT_END_LICENSE$ ** ****************************************************************************/ //! [0] int number = 6; void method1() { number *= 5; number /= 4; } void method2() { number *= 3; number /= 2; } //! [0] //! [1] // method1() number *= 5; // number is now 30 number /= 4; // number is now 7 // method2() number *= 3; // number is now 21 number /= 2; // number is now 10 //! [1] //! [2] // Thread 1 calls method1() number *= 5; // number is now 30 // Thread 2 calls method2(). // // Most likely Thread 1 has been put to sleep by the operating // system to allow Thread 2 to run. number *= 3; // number is now 90 number /= 2; // number is now 45 // Thread 1 finishes executing. number /= 4; // number is now 11, instead of 10 //! [2] //! [3] QMutex mutex; int number = 6; void method1() { mutex.lock(); number *= 5; number /= 4; mutex.unlock(); } void method2() { mutex.lock(); number *= 3; number /= 2; mutex.unlock(); } //! [3] //! [4] int complexFunction(int flag) { mutex.lock(); int retVal = 0; switch (flag) { case 0: case 1: mutex.unlock(); return moreComplexFunction(flag); case 2: { int status = anotherFunction(); if (status < 0) { mutex.unlock(); return -2; } retVal = status + flag; } break; default: if (flag > 10) { mutex.unlock(); return -1; } break; } mutex.unlock(); return retVal; } //! [4] //! [5] int complexFunction(int flag) { QMutexLocker locker(&mutex); int retVal = 0; switch (flag) { case 0: case 1: return moreComplexFunction(flag); case 2: { int status = anotherFunction(); if (status < 0) return -2; retVal = status + flag; } break; default: if (flag > 10) return -1; break; } return retVal; } //! [5] //! [6] class SignalWaiter { private: QMutexLocker locker; public: SignalWaiter(QMutex *mutex) : locker(mutex) { } void waitForSignal() { ... while (!signalled) waitCondition.wait(locker.mutex()); ... } }; //! [6]