KDE Partition Manager uses QFile to write some data directly to raw block devices, e.g. /dev/sda. This worked with Qt 4.x but it stopped working after porting to Qt5.

The problem is that after opening /dev/sda as a file, QFile thinks that it is sequential device even though block devices are random access devices.

I'm attaching test program (unfortunately it has to be run as root because block devices are not accessible to other users). When I run "sudo test" it prints true (so /dev/sda is reported as sequential).