I've got a bootable flash memory card with an Ubuntu operating system on it along with other programs, ie. a fully functioning system I use on a single-board computer. I'd like to back it up on my PC's (also running Ubuntu) hard disk, but without wasting space as the
dd command would do (because it also backs up free space). The flash drive is 32GB big and only 10% full. It doesn't have any partitions on it.
What are the options?
EDIT the flash drive is formatted as
partimage doesn't apply.