tools/appliance/definitions/builtin/zerodisk.sh - cloudstack - Git at Google

 # Zero out the free space to save space in the final image:
 dd if=/dev/zero of=/EMPTY bs=1M
 rm -f /EMPTY
	# Zero out the free space to save space in the final image:
	dd if=/dev/zero of=/EMPTY bs=1M
	rm -f /EMPTY