>> If the underlying media were write-protected, as with the button
>> on a VAX RA81 drive, the 'clean-up' write/erase would fail.
>
> Good one! Those were real computers! I really liked the VAX file system model
> with recoverable file versioning. Progress isn't always forward.


It seems like YAFFS would be a perfect candidate for implementing
recoverable file versioning.  Is that something you've ever considered
doing?