Naming of subvolumes

[Richard Hughes <hughsient@gmail.com>]

I'm planning to use "btrfs subvolume snapshot -r <name>" in the system
upgrade functionality[1] if the user is using btrfs for their root file
system. We've got most of the bits in place already for Fedora 18.

One think that confuses me is the convention for the naming of
snapshots. Is there any conventions or prior art there? Can I add
metadata to the snapshot so that I don't have encode everything in the
snapshot name itself?

Also, being able to do a snapshot using a libbtrfs (or whatever) would
be much preferable to exec'ing the btrfs command and then trying to
parse the exit code and any stderr. I don't know if this kind of thing
is the norm for filesystem utilities, but a versioned shared library to
use would be awesome.

Any advice welcome, thanks.

Richard
(PackageKit author)

[1] https://fedoraproject.org/wiki/Features/OfflineSystemUpdates