>> What I think is happening to you is that [...] on umount, [the
>> filesystem code] flushes [its] idea of superblock to disk, actually
>> overwriting your changes.

> So perhaps tunefs should be able to modify the in memory idea of the
> superblock.  (similar to the disklabel dual
> kernel-ioctl/write-to-disk method)  Or maybe cause it to be discarded
> and re-read.

Both of those sound dangerous to me.  It sounds better, to me, to just
document that tunefs needs to be run on filesystems not mounted
read/write (unmounted or mounted RO).  And then make certain that when
going from RO to RW - or any other `-o update` operation - the
superblock gets reread.

					der Mouse

			       mouse@rodents.montreal.qc.ca
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