disk Partition label changes and reflecting them in /dev/disks-by-label/

[Linda Walsh <lkml@tlinx.org>]

 

If I have a disk with no mounted partitions and I change the partition 
order,
the OS will re-read the new partition and life goes on.

However, if I create or change a new disk label, it seems label programs
(and users) should have an option to reread the labels after the 
modification.

Ideally any prog that changes a Label or UUID would trigger an update
of what's in /dev/disks to reflect the new 'reality'.

Currently, I go through through a seemingly bizarre ritual of invoking
unmounting all other partitions on the same disk, then becoming root,
running fdisk on the disk, then just exiting with "w".  This triggers
a reread of not only the partition table, but also the new labels. 

However, I find this far less than ideal.  Is there a better way, or could
there be a better way to update new Labels and UUID's that are actually
on a disk -- perhaps even as an ordinary user command (since it would be
a read-only operation on the disk that simply updates /dev/disk to reflect
what's really there -- Especially being able to change only the label (or
UUID), only on one partition w/o having to actually unmount other file 
systems
on the disk....?

Already implemented?  Or doable?  Or bad idea?

Thanks,
-linda