On 26.06.2021 08:17, NeilBrown wrote: > On Sat, 26 Jun 2021, Bart Van Assche wrote: >> On 6/25/21 5:54 PM, NeilBrown wrote: >>> On Sat, 26 Jun 2021, Martin Steigerwald wrote: >>>> And that Baloo needs an "invariant" for >>>> a file. See comment #11 of that bug report: >>> >>> That is really hard to provide in general. Possibly the best approach >>> is to use the statfs() systemcall to get the "f_fsid" field. This is >>> 64bits. It is not supported uniformly well by all filesystems, but I >>> think it is at least not worse than using the device number. For a lot >>> of older filesystems it is just an encoding of the device number. >>> >>> For btrfs, xfs, ext4 it is much much better. >> >> How about combining the UUID of the partition with the file path? An >> example from one of the VMs on my workstation: > > A btrfs filesystem can span multiple partitions, and those partitions > can be added and removed dynamically. So you could migrated from one to > another. > I suspect it was intended to be "filesytemm UUID". At least that is the field in lsblk output that was referenced. > f_fsid really is best for any modern filesystem. > > NeilBrown >
