In particular the 'read' part plays 'hunt the disklabel' in order to get a
label into a local buffer - from where it can be displayed/edited.
The 'write' part makes a separate scan of the disk looking for places to
write the label.
The main changes are:
- It can no longer write the first 8k of the mbr to the pbr (or v.v.)
- All labels on the disk (that it can find) get updated during a write
- With -A all the labels are displayed (inc. those deleted by -D)
- Addition of -D which will delete (by one's complimenting dk_magic{2}) and
existing labels before writing labels to the expected locations.
- -v gives some verbose output to stderr, -vv more etc
A better basis for processing incorrect endian labels, or labels from other
architectures.
- add a function to print only one partition's info.
- print the partition information if it was modified in interactive mode.
- improve on the chaining code. [still assumes that partition offsets increase
monotonically]. We could check for overlap too.
snj