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To: Andrew Gierth <andrew@erlenstar.demon.co.uk>
cc: Curt Sampson <cjs@portal.ca>, hackers@freebsd.org
Subject: Re: /etc/netstart bogons.. 
In-reply-to: Your message of "26 Apr 1997 11:23:39 +0100."
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Date: Sun, 27 Apr 1997 11:17:10 +1000
From: David Nugent <davidn@labs.usn.blaze.net.au>
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> > At 11:54 AM 4/24/97 -0700, Curt Sampson wrote:
> >> Thus, having the variable set to "" or unset (they're the
> >> same thing in /bin/sh)
> 
> Can't let this slip past: "" and unset are certainly not the
> same in sh.

Well, no of course not, technically.

However, the manner in which the variables are tested allows it
to amount to the same thing. ie. an unset variable evaluates to "".
Curt's addition of "in /bin/sh" is the clue; unlike the (imho broken)
/bin/csh semantics which error on reference to an unset (as distinct
from empty) variable.

David Nugent - Unique Computing Pty Ltd - Melbourne, Australia
Voice +61-3-9791-9547  Data/BBS +61-3-9792-3507  3:632/348@fidonet
davidn@freebsd.org davidn@blaze.net.au http://www.blaze.net.au/~davidn/