How to get Date & Time from NTP server and update my system clock.... using QT Widget application

Sekhar

Can any one tell me how to get Date and Time from NTP server and synchronize with system clock? using QT widget application?
i got a code from internet but it does not working.....

mainWindow.cpp

#include "mainwindow.h"
#include "ui_mainwindow.h"

unsigned char buf[10];

MainWindow::MainWindow(QWidget *parent) :
    QMainWindow(parent),
    ui(new Ui::MainWindow)
{
    ui->setupUi(this);
}

MainWindow::~MainWindow()
{
    delete ui;
    udpSocket->close();
}

void MainWindow::changeEvent(QEvent *e)
{
    QMainWindow::changeEvent(e);
    switch (e->type()) {
    case QEvent::LanguageChange:
        ui->retranslateUi(this);
        break;
    default:
        break;
    }
}

void MainWindow::on_Update_clicked()
{
    QHostInfo info = QHostInfo::fromName("time.nist.gov");//("0.pool.ntp.org");
    QString ipAddress = info.addresses().first().toString();
    ui->ipAddress->setText(ipAddress);
    udpSocket = new QUdpSocket(this);

    connect(udpSocket, SIGNAL(readyRead()), this, SLOT(readPendingDatagrams()));
    connect(udpSocket, SIGNAL(connected()), this, SLOT(connectSuccsess()));
    udpSocket->abort();
//    udpSocket->connectToHost("time.nist.gov",123);//("0.pool.ntp.org", 123);

}
void MainWindow::readPendingDatagrams()
{
   // ui->statusLabel->setText("Reading...");
    QByteArray newTime;
    QDateTime Epoch(QDate(1900, 1, 1));
    QDateTime unixStart(QDate(1970, 1, 1));
    do {
        newTime.resize(udpSocket->pendingDatagramSize());
        udpSocket->read(newTime.data(), newTime.size());
    } while(udpSocket->hasPendingDatagrams());

    QByteArray TransmitTimeStamp ;
    TransmitTimeStamp = newTime.right(8);

    quint64 seconds = 0;
    for (int i=0; i<= 3; ++i)
    {
         seconds = (seconds << 8) | TransmitTimeStamp[i];
    }
    ui->plainTextEdit->appendPlainText(QString::number(seconds, 10));
    QDateTime newestTime;
    newestTime.setTime_t(seconds - Epoch.secsTo(unixStart));
     ui->plainTextEdit->appendPlainText(newestTime.toString());
}
void MainWindow::connectSuccsess()
{
   // ui->time->setText("Connected");
    ui->time->setText("Connected-jkjlk");
    QByteArray timeRequest(48, 0);
    timeRequest[0] = '\x23';
    udpSocket->flush();
    udpSocket->write(timeRequest);
}

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////

MainWindow.h 

#ifndef MAINWINDOW_H
#define MAINWINDOW_H

#include <QMainWindow>
#include <QAbstractSocket>
#include <QUdpSocket>
#include <QHostInfo>
#include <QHostAddress>
#include <QDateTime>

namespace Ui {
class MainWindow;
}

class MainWindow : public QMainWindow
{
    Q_OBJECT

public:
    explicit MainWindow(QWidget *parent = 0);
    ~MainWindow();

protected:
    void changeEvent(QEvent *e);

private slots:
    void on_Update_clicked();
    void readPendingDatagrams();
    void connectSuccsess();
private:
    Ui::MainWindow *ui;
    QUdpSocket *udpSocket;
};

#endif // MAINWINDOW_H

jsulm

@Sekhar said in How to get Date & Time from NTP server and update my system clock.... using QT Widget application:

i got a code from internet but it does not working

Please tell us what exactly does not work, or do you expect us to guess?

SGaist

Hi,

And to add to @jsulm, this is usually a task managed by a system service. You will also have to request higher privilege to modify your system's clock.

Sekhar

@jsulm
thanks for your response. i would like to get the date and time from NTP server not form System(Date & Time) this is my primary task. I don't know how to get the data from NTP server.
and in the above code i was tried but got the wrong timestamp(date and time) like 16th jan 2036.