I downloaded a Debian DVD and following the docs mounted a USB and simply did this:
cp /dev/sdb mydebiandvd.iso sync
After running these commands I ran
lsblk and found the sdb thumb drive said it had all space free.
But when I booted to the USB the Debian install screen popped up!
Is cp doing something special when I copied the ISO directly to the device (not just a partition on the device). Does it do something like run the dd command in the background? Really curious about what's actually happening here.
I believe sync just makes sure the USB isn't locked before it can be unmounted?