Lisa Source Code

[Chuck Guzis]

On 4/9/21 6:05 AM, Paul Koning via cctalk wrote:
> Linked lists go back a long way.  FAT is one, in a sense.  DECtape file systems for DOS (also RSTS) are linked, in the blocks.  The same goes for the CDC 6000 file system (more precisely, it has contiguous blocks within a track, and links from the last block in the track to the next track number).
> 
> 	paul
> 
>> On Apr 9, 2021, at 12:27 AM, Richard Sheppard via cctalk <cctalk at classiccmp.org> wrote:
>>
>> I believe the original Amiga file system also used a linked-list approach. That way you could, theoretically, reconstruct a file from any one of it’s data blocks.
>> Richard


The point with the WORM drive setup I described, is that one may recover
*every* file ever written, however the name and attributes of the file
may not be recoverable, being stored in the tree, which may not be
readable.   That is, the linked list may be intact, but the tree not so
or vice-versa.  The advantage is that searching for a given file is
faster using a tree than it would be traversing a list.

Reading old papers on the subject, it seems that old optical
phase-change storage, while permanent may not have been absolutely reliable.

I should also mention that although the WORM discs do store quite a bit
of data (in my case 470MB per side), they're not very fast.  More
floppy-disk speed than hard disk.

--Chuck