[SOLVED] How to detect USB devices

[alsa]

My aim is to save a txt file from my Qt app to an external device (SD card, USB pendrive...). The app is created for an embedded system.
My problem is: how detect which USB device is connected when I inserted a USB pen, in such a way that I can save my file in it?
Which is the best method using Qt?

[McLion]

Usually, mounting storage devices is handled by the OS.
What is the target OS for which you are developing?

[alsa]

I'm developing on Ubuntu 14.04 for a Single Board Computer Variscite (its OS is Linux-embedded)

[Renn]

If your goal is only to store data, use this command QFileDialog::getSaveFileName(); If your goal is only to store data, use this command. Do not forget the file header #include <QFileDialog>

[McLion]

@alsa
Does your eLinux mount newly attached storage devices automatically to a mount point or does it only create a device file?

I had the same task on eLinux as well. My system did create the device file only (busybox with mdev). I used a QFileSystemWatcher to detect changes in /dev, ie. attached sdan and acted on that with mounting/unmounting the device.

[alsa]

It only creates a device file

[McLion]

@alsa
Then look into QFileSystemWatcher.

[McLion]

To start:

// prepare FS watcher to detect added USB memory
FSwatcher = new QFileSystemWatcher(this);
FSwatcher->addPath("/dev");
connect(FSwatcher, SIGNAL(directoryChanged(QString)), this, SLOT(showModifiedDirectory(QString)));

HTH
McL

[ealltech]

This post is deleted!

[Jim S]

@McLion Would you currently prefer this approach over Qt D-Bus for it's simplicity?