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/****************************************************************************
**
** Copyright (C) 2013 Digia Plc and/or its subsidiary(-ies).
** Contact: http://www.qt-project.org/legal
**
** This file is part of the Qt Solutions component.
**
** $QT_BEGIN_LICENSE:BSD$
** You may use this file under the terms of the BSD license as follows:
**
** "Redistribution and use in source and binary forms, with or without
** modification, are permitted provided that the following conditions are
** met:
** * Redistributions of source code must retain the above copyright
** notice, this list of conditions and the following disclaimer.
** * Redistributions in binary form must reproduce the above copyright
** notice, this list of conditions and the following disclaimer in
** the documentation and/or other materials provided with the
** distribution.
** * Neither the name of Digia Plc and its Subsidiary(-ies) nor the names
** of its contributors may be used to endorse or promote products derived
** from this software without specific prior written permission.
**
**
** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE."
**
** $QT_END_LICENSE$
**
****************************************************************************/
#include <stdio.h>
#include <QTextStream>
#include <qtlockedfile.h>
int main()
{
QTextStream qout(stdout);
QTextStream qin(stdin);
qout << "---===>>>> File locking example <<<<===---\n";
QtLockedFile lf("foo");
lf.open(QFile::ReadWrite);
QString line;
bool blocking = true;
while (line != "q") {
int m = lf.lockMode();
if (m == 0)
qout << "\n[*] You have no locks.";
else if (m == QFile::ReadOnly)
qout << "\n[*] You have a read lock.";
else
qout << "\n[*] You have a read/write lock.";
qout << " Blocking wait is ";
if (blocking)
qout << "ON.\n";
else
qout << "OFF.\n";
qout << "Acquire [r]ead lock, read/[w]rite lock, re[l]ease lock, [t]oggle or [q]uit? ";
qout.flush();
line = qin.readLine();
if (line.isNull())
break;
if (line == "r") {
qout << "Acquiring a read lock... ";
qout.flush();
if (lf.lock(QtLockedFile::ReadLock, blocking))
qout << "done!\n";
else
qout << "not currently possible!\n";
} else if (line == "w") {
qout << "Acquiring a read/write lock... ";
qout.flush();
if (lf.lock(QtLockedFile::WriteLock, blocking))
qout << "done!\n";
else
qout << "not currently possible!\n";
} else if (line == "l") {
qout << "Releasing lock... ";
qout.flush();
lf.unlock();
qout << "done!\n";
} else if (line == "t") {
blocking = !blocking;
}
qout.flush();
}
}
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