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/****************************************************************************
**
** 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.
**
**
**
**
**
**
**
**
** $QT_END_LICENSE$
**
****************************************************************************/

#include <QFile>
#include <QTextStream>

static void process_line(const QByteArray &)
{
}

static void process_line(const QString &)
{
}

static void noStream_snippet()
{
//! [0]
    QFile file("in.txt");
    if (!file.open(QIODevice::ReadOnly | QIODevice::Text))
        return;

    while (!file.atEnd()) {
        QByteArray line = file.readLine();
        process_line(line);
    }
//! [0]
}

static void readTextStream_snippet()
{
//! [1]
    QFile file("in.txt");
    if (!file.open(QIODevice::ReadOnly | QIODevice::Text))
        return;

    QTextStream in(&file);
    while (!in.atEnd()) {
        QString line = in.readLine();
        process_line(line);
    }
//! [1]
}

static void writeTextStream_snippet()
{
//! [2]
    QFile file("out.txt");
    if (!file.open(QIODevice::WriteOnly | QIODevice::Text))
        return;

    QTextStream out(&file);
    out << "The magic number is: " << 49 << "\n";
//! [2]
}

static void writeTextStream_snippet()
{
    QFile file("out.dat");
    if (!file.open(QIODevice::WriteOnly))
        return;

    QDataStream out(&file);
    out << "The magic number is: " << 49 << "\n";
}

static void readRegularEmptyFile_snippet()
{
//! [3]
    QFile file("/proc/modules");
    if (!file.open(QIODevice::ReadOnly | QIODevice::Text))
        return;

    QTextStream in(&file);
    QString line = in.readLine();
    while (!line.isNull()) {
        process_line(line);
        line = in.readLine();
    }
//! [3]
}

int main()
{
    lineByLine_snippet();
    writeStream_snippet();
}