FILE=file_name; CHUNK=$((64*1024*1024)); SIZE=$(stat -c "%s" $FILE); for ((i=0; i < $SIZE; i+=$CHUNK)); do losetup --find --show --offset=$i --sizelimit=$CHUNK $FILE; done

via http://www.commandlinefu.com/commands/view/13735/split-a-large-file-without-wasting-disk-space