[Oberon] OFS directory-format documented ?

easlab at absamail.co.za easlab at absamail.co.za
Wed Nov 28 08:08:37 MET 2007

Is there any documentation/description available for 
the N-O file system [OFS] structure, without reading the
source code files ?

Using Partitions.ShowBlocks I can see that:
- the directory starts at block 1032,
- each entry is 40 bytes wide,
- they are [re]arranged alphbetically by fileID,
- the 'table' starts:
00: <4 bytes> <number of dir-entries>
10:<32 chars for 1st file ID> <8 bytes= 2 words>
    seemingly only the 1st word after the ID-field is used?
Simplistically this would be an offset ?
But when I re-formatted [which I later discovered does 
NOT delete/reset previous bytes] and entered 4 'new'
files: one, two, three, four, of sizes as below, I see:

FuleID arg-word File-size Dif-words
=============== use const width font to view===
one      5829     75       29
two      5858     75       29
three    5887     75       29
four     5916     115      29

So the [apparently redundant] word-val 29 is 
independant of the file size ?

In fact for a big-directory all the 'arg-words' are 
multiples of 29; and the 1st chronologically entered
File's arg-word: 5829; equals 201*29.

Thanks for any feedback,

== Chris Glur.

PS. yes you guessed that I want to recover some lost
valuable files.

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