unzip and untar into new directory

[jshafferman]

I have a file that is file.tar.gz and I would like to implement an open function from GUI menu that allows the user to select the tar.gz file and the application unzip, untar, and place those files in a specified directory. I don't think there is a Qt function that can do all of the above (but maybe some) but I was curious on any suggestions on how to implement this functionality.

Thanks for any help!

[amleto]

use QProcess to start an unzip utility e.g. 7z or equivalent.

[jshafferman]

Is there anyway to do it without using QProcess? I am trying to avoid needing to install any third party software with my application.

[jshafferman]

Ok so I have decided to use peazip for the QProcess but I do not understand how to use QProcess very well. I downloaded the peazip portable and placed the executable in the same directory as my application. I tried to do the following:

MainWindow::open()
{
  QProcess *unarchive = new QProcess(this);
  QStringList arguments;
  arguments << "-ext2here" << "file.tar.gz";
  unarchive->start("peazip", arguments);
 
  // other things happen
}

MainWindow::open()
{
  QProcess *unarchive = new QProcess(this);
  QStringList arguments;
  arguments << "-ext2here" << "file.tar.gz";
  unarchive->start("peazip", arguments);

  // other things happen
}

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Unfortunately nothing seems to be happening so I am curious what I am missing. Thanks for any help!

[ChrisW67]

What sort of 'nothing' is happening? Is the QProcess object emitting an error() signal? Where is the peazip executable in relation to the current working directory of your process?

[amleto]

how are you testing? by debugging through an IDE or just running your program 'manually'? If the former, you probably just have a problem where your app is not run from the same location as the unzip utility

[jshafferman]

Duh! I was running it in debug mode and didn't put the peazip executable in the correct directory... It seems to be working fine now!!

I do have another question that might be answered here, can you do an OS check with Qt? I don't see a Linux version of the peazip portable so I am thinking I will need a #if statement to check for Windows OS and use peazip but if it is Linux use standard unix unarchiving/archiving commands. How would you call the unix terminal to unzip and untar a file?

Thanks again for any help!

[jshafferman]

So I am able to have the QProcess execute the unzip and untar but when I try and run something after the untar nothing appears to be happening.

QMainWindow::open()
{
   if(okToContinue())
  {
       QString fileName = QFileDialog::getOpenFileName(this, tr("Open file.tar.gz file"), ".", tr("gzip tarball"
                                                                 "(*.tar.gz)"));
 
        if(!fileName.isEmpty())
       {
            QProcess *unarchive = new QProcess(this);
 
            QStringList arguments;
            arguments << "-ext2here" << fileName;
            unarchive->start("peazip", arguments);
 
            if(unarchive->waitForFinished())
            {
                fileName.remove(".gz");
                arguments.clear();
                arguments << "-ext2here" << fileName;
                int exitCode = unarchive->execute("peazip", arguments);
 
                if(unarchive->waitForFinish())
                {
                   fileName.remove("file.tar");
                   // this is the path that is extracted from tar and the .csv is what I am after
                   fileName.append(("tmp/file/A.csv"));
 
                   loadFile(fileName);
               }
           }
      }
   }
}

QMainWindow::open()
{
   if(okToContinue())
  {
       QString fileName = QFileDialog::getOpenFileName(this, tr("Open file.tar.gz file"), ".", tr("gzip tarball"
                                                                 "(*.tar.gz)"));

        if(!fileName.isEmpty())
       {
            QProcess *unarchive = new QProcess(this);

            QStringList arguments;
            arguments << "-ext2here" << fileName;
            unarchive->start("peazip", arguments);

            if(unarchive->waitForFinished())
            {
                fileName.remove(".gz");
                arguments.clear();
                arguments << "-ext2here" << fileName;
                int exitCode = unarchive->execute("peazip", arguments);

                if(unarchive->waitForFinish())
                {
                   fileName.remove("file.tar");
                   // this is the path that is extracted from tar and the .csv is what I am after
                   fileName.append(("tmp/file/A.csv"));

                   loadFile(fileName);
               }
           }
      }
   }
}

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It never seems to make it inside the second waitForFinish if statement. What am I doing wrong?

Thanks for help!

[amleto]

why are you mixing execute/start? Why are you allocating on the heap when you only want a local instance?

I believe the problem is that you are using execute, which is a static method, therefore the finished state required for 'waitForFinished' is not modified.