Single Application Instance

[lni]

I thought you can only have 1 instance of QApplication? That instance is stored in qApp as global vairable? Do I misunderstand you?

So, do

if ( qApp != NULL ) {
// application has been created
} else {
// create an application
}

After reading the page at http://doc.trolltech.com/solutions/4...ion/index.html, I understand what it is. But why I don't have QtSingleApplication in my package?

I think it is very useful class. Is it possible to detect a running application in different machine? I am currently having several processes across different machines writing to same files, and I have to create/delete a file.lock to prevent the processes writing to the same file at the same time...

[Lykurg]

But why I don't have QtSingleApplication in my package?

It's only for commercial use: http://www.qtsoftware.com/products/a...leapplication/