Copying the file content

[A Former User]

@jsulm ```

"C:/Users/user/Documents/MyThread/deneme.txt"

This is my old file path, the new one is in different name

[jsulm]

@suslucoder And what exactly does not work: it does not copy the file?
Please post the new apth also, so we can make sure it is not wrong.
Does the old file exist?
Also, what does copy return (true/false)?

[A Former User]

@jsulm It does not copy the file. It is in my thread.

void MyThread::writeData()
{

    QFile::copy("C:/Users/user/Documents/MyThread/deneme.txt", "C:/Users/user/Documents/MyThread/new.txt");
    if(!file.open(QIODevice::ReadOnly))
    {
        QTextStream in(&file2);
        while(!in.atEnd())
        {
            QString line2=in.readAll();
            QStringList list = line2.split(QLatin1Char(' '), Qt::SkipEmptyParts);
            for(const QString &entry : list)
            {
                double num = entry.toDouble();
                queue.enqueue(num);
                qDebug() << num;
            }
        }
    }
    qDebug() << "im working in writing thread";

    emit writingDone();

}

qDebug does not give anytghing on the secreen. And yes the old file exist. I can read its contents

[jsulm]

@suslucoder said in Copying the fle content:

It does not copy the file

That I already understood.
Again: what does QFile::copy return?

I also do not understand what how this file copy is related to the other code:

if(!file.open(QIODevice::ReadOnly)) // What is file here? What file are you trying to pen here?

[sierdzio]

@suslucoder said in Copying the fle content:

qDebug does not give anytghing on the secreen

This means that MyThread::writeData() function is not called at all! And that implies the problem lies somewhere else (not in QFile::copy()).

[A Former User]

@sierdzio I've already called it with start() function. Doesnt it started the thread?

[sierdzio]

Yes, start() starts the thread, but it does not mean your writeData() is called. If that were true, you would see your qDebug() output, because it is not in any if conditions - it should be printed every time writeData() is called.

[A Former User]

@sierdzio yes you are right. I've called the function. Thread is working now. But copying issue does not work.

[sierdzio]

I don't know either, you have not shown any code or stated how you want it all to work... so all I can say is "read the docs" :D QThread has a nice example and detailed description: https://doc.qt.io/qt-5/qthread.html#details

[A Former User]

@sierdzio I just want, when writeData() thread is called, copy the contents into new txt.

[J.Hilk]

@suslucoder
QThread has a started signal you connect that signal to your slot

[A Former User]

@J-Hilk My thread has working now. But copying does not occur

[jsulm]

@suslucoder So, what does copy() return?

[A Former User]

@jsulm it returns nothing, Either true or false

[jsulm]

@suslucoder said in Copying the file content:

it returns nothing, Either true or false

?
It returns a boolean.
Again: what does it return?!

qDebug() << QFile::copy("C:/Users/user/Documents/MyThread/deneme.txt", "C:/Users/user/Documents/MyThread/new.txt");

[J.Hilk]

@suslucoder then the function isn't called.

Please post what you actually have in your code, otherwise no-one will be able to help you

[A Former User]

@jsulm it returns false.

#include "mythread.h"
#include "mainwindow.h"
#include <QtCore>
#include <QDebug>
#include <QFile>
#include <QTimer>
#include <QThread>
#include <QMutex>
#include <QQueue>
#include <QMessageBox>
#include <QApplication>
#include <QtWidgets/QApplication>
#include <QtWidgets/QMainWindow>
#include <QFileDialog>
#include <QMainWindow>

QFile file("C:/Users/ilknu/Documents/MyThread/deneme.txt");


MyThread::MyThread(QObject* parent)
    : QThread(parent)
{
    writeData();
}

MyThread::~MyThread()
{

}

void MyThread::writeData()
{
    QFile file2("C:/Users/ilknu/Documents/MyThread/new.txt");
    QFile::copy("C:/Users/ilknu/Documents/MyThread/deneme.txt","C:/Users/ilknu/Documents/MyThread/new.txt" );
    qDebug() << QFile::copy("C:/Users/user/Documents/MyThread/deneme.txt", "C:/Users/user/Documents/MyThread/new.txt");
    qDebug() << "im working in writing thread";

    emit writingDone();

}

void MyThread::run()  //Reading file from txt with thread1
{

    if (file.open(QIODevice::ReadOnly))
    {
        QTextStream in (&file);
        while (!in.atEnd())
        {
            QString line = in.readAll();
            QStringList list = line.split(QLatin1Char(' '), Qt::SkipEmptyParts);
            for(const QString &entry : list)
            {
                double num = entry.toDouble();
                queue.enqueue(num);

            }


            qDebug()<< "im running on worker thread " <<line;

        } // for
    } // while
    file.close();
} // if

[sierdzio]

Check if it exists:

qDebug() << "Source exists?" << QFile::exists("C:/Users/ilknu/Documents/MyThread/deneme.txt");
qDebug() << "Destination exists?" << QFile::exists("C:/Users/ilknu/Documents/MyThread/new.txt");

You need to check destination because:

If a file with the name newName already exists, copy() returns false (i.e., QFile will not overwrite it).

[JonB]

@suslucoder
Did you read the documentation of QFile::Copy() for yourself?

Note that if a file with the name newName already exists, copy() returns false (i.e. QFile will not overwrite it).

So, does the destination file already exist? Does the source file also exist?

[SGaist]

Hi,

@suslucoder said in Copying the file content:

QFile::copy("C:/Users/ilknu/Documents/MyThread/deneme.txt","C:/Users/ilknu/Documents/MyThread/new.txt" );
qDebug() << QFile::copy("C:/Users/user/Documents/MyThread/deneme.txt", "C:/Users/user/Documents/MyThread/new.txt");

You do not have the same paths in the qDebug and the previous line.
You do realise that you are copying it twice ?