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/****************************************************************************
**
** Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies).
** All rights reserved.
** Contact: Nokia Corporation (qt-info@nokia.com)
**
** This file is part of the QtNetwork module 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.
**
**
**
**
**
**
**
**
** $QT_END_LICENSE$
**
****************************************************************************/
#include <QtCore>
void slowOperation1()
{
static char buf[256];
for (int i = 0; i < (1<<20); ++i)
buf[i % sizeof buf] = i;
}
void slowOperation2(int) { slowOperation1(); }
void startExample()
{
//![0]
QElapsedTimer timer;
timer.start();
slowOperation1();
qDebug() << "The slow operation took" << timer.elapsed() << "milliseconds";
//![0]
}
//![1]
void executeSlowOperations(int timeout)
{
QElapsedTimer timer;
timer.start();
slowOperation1();
int remainingTime = timeout - timer.elapsed();
if (remainingTime > 0)
slowOperation2(remainingTime);
}
//![1]
//![2]
void executeOperationsForTime(int ms)
{
QElapsedTimer timer;
timer.start();
while (!timer.hasExpired(ms))
slowOperation1();
}
//![2]
int restartExample()
{
//![3]
QElapsedTimer timer;
int count = 1;
timer.start();
do {
count *= 2;
slowOperation2(count);
} while (timer.restart() < 250);
return count;
//![3]
}
int main(int argc, char **argv)
{
QCoreApplication app(argc, argv);
startExample();
restartExample();
executeSlowOperations(5);
executeOperationsForTime(5);
}
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