>From: "Kelly Yancey" <kby...@alcnet.com>
>Date: Tue, 20 Jul 1999 13:28:21 -0400

>  On recent thought though, I seem to recall having read in the 4.4BSD
>Daemon book that having the kernel zero memory is not the preferred
>practice, but present because when they tried to stop many progrems dies
>which assumed memory was initialized to zero. If I am remembering that
>correctly, then, the only real concern is that one day we may want to kernel
>to stop zeroing pages, in which case the extra logic in calloc() would be
>for nought.

I'd *think* you'd want to ensure that lack of initializing the data
didn't become a way for unintended access to data that should not have
been available to the process in question.  (Ugh.  Too many negatives in
there.)

Anyway, the process merely reminded me of the ability on a system I used
28+ years ago, where a FORTRAN program could open a file for writing,
but read it first... and possibly find some "interesting" information
left over from a previous program....  (No, that wasn't a UNIX system,
let alone FreeBSD.  :-})

Cheers,
david
-- 
David Wolfskill         d...@whistle.com                UNIX System 
Administrator
voice: (650) 577-7158   pager: (888) 347-0197   FAX: (650) 372-5915


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