Beware of Blindly Un-SHARing a File

[Larry Lippman]

In article <403 at ukecc.UUCP>, edward at ukecc.UUCP (Edward C. Bennett) writes:
>> 
>>         Part of the joke was funny, and part of it was not so funny.  Anyone
>> naive enough to believe that a deleted file could be recovered was well
>> fooled by the introductory remarks and the phony manual page.
> 
> 	But you can recover an unlinked file! I know, I've had to do it.
> You must unmount the file system and search the free list for your data.
> It's a PITA, but worth it if you lose something big.

	I don't claim to be a UNIX internals expert (I have enough trouble
writing I/O drivers :-) ), but don't most ports of UNIX zero disk blocks after
an unlink(2)?  As I seem to recall, unlink(2) is derived from unlink.s, which
is assembly language specific for the given machine.  And unlink.s contains
a routine _unlink which fills the disk blocks with .word defined as 0x0000.
	Any comments from those who know more?

==>  Larry Lippman @ Recognition Research Corp., Clarence, New York
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