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Re: PC disk wipe software

In a message dated 95-10-09 12:34:33 EDT, you write:

>>PC Tools has a wipe program that will either wipe individual files, or
>>wipe all unallocated diskspace. It also allows you to choose the level
>>of wipe (single overwrite, multiple, etc).
>There has been considerable discussion on the MCIP list about how most
>*Mac* programs that purport to do this, like Burn, for example, leave stuff
>over in disk blocks. My understanding is that this is not a trivial
>problem, and it occurs in MUSH-DOS as well....
>Bob Hettinga

Actually not a problem for mess-DOS: just overwrite to the next multiple of
the allocation unit size. Trivial indeed.  What you must *not* do is just
write to the end of current file ... you have to extend.  Good idea too is to
flush file buffers/reset disk subsystem before the next file writes so that
buffer garbage doesn't get stuck in at end of last sector(s) of new files.