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Date: Wed, 19 Nov 1997 20:58:00 -0500 (EST)
From: "Matthew N. Dodd" <winter@jurai.net>
To: "Brian N. Handy" <handy@sag.space.lockheed.com>
cc: Sean Eric Fagan <sef@kithrup.com>, hackers@freebsd.org
Subject: Re: Mail spam, sigh...
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On Wed, 19 Nov 1997, Brian N. Handy wrote:
> I'd also like an easy-drop-in-way to drop email from sites that don't show
> up in the nameserver.  (Maybe this is easy, I haven't done my research.) 

Svalid_host

# check for valid domain name
R$*                             $: <?> $>3 $1
R<?> $* < @ $+ . >              $: $1 @ $2
R<?> $* < @ $+ >                $#error $@ 4.5.1 $: "451 Domain must resolve"


I'm still working on one that checks forward and reverse and fusses if
they do not match.

/* 
   Matthew N. Dodd		| A memory retaining a love you had for life	
   winter@jurai.net		| As cruel as it seems nothing ever seems to
   http://www.jurai.net/~winter | go right - FLA M 3.1:53	
*/