🚀 go-pugleaf

edguer@charlie.ces.cwru.edu writes:
>  According to RFC822, you are correct.  According to RFC822 however,
>  there is no such thing as a "!" path.

True, but there is such a thing as a "local part," with which I am
free to do as I please, including a rewrite into @-format.

>  Bang paths do qualify in my opinion because of RFC976.  RFC976 says
>  that a gateway should change an RFC822 source route into an RFC976
>  bang path when sending to the next hop via UUCP.  This means that
>  if you receive a bang path via UUCP you may be receiving a valid 
>  RFC822 source route from another site that is following the rules.
>  This is why I feel that to properly comply with the mail RFC's you 
>  should treat ALL bang paths as valid source routes.  No active rerouting.

I see what you're getting at; the point is well taken.  But I think
there are problems with the interpretation of it.

Passive rerouting, when the first specified host in the path is
unknown, is a violation of the source-route rules as much as active
rerouting.  If we're going to attach strict source route rules to
!-paths, then we have to obey those rules.  Those rules say that, if
you give me
	<@a.b,@c.d,@e.f:u@g.h>
then I must hand the mail _directly_ to a.b.  It doesn't say that I
may find my own best intermediate-hop route to a.b; it says I have to
go straight there.

On the Internet, this is fine, since one assumes complete
interconnectivity.

I can't do that in the Land of UUCP, in general.

An indirect proof for everyone...

[1] Condition: "!-paths" are to be equated with "source routes."
[2] Conclusion: Interpretation of source routes according to the RFCs
    requires that a relay host send directly to the first routed host
    specified in the source route.
[3] In UUCP, a relay host cannot, in general, be counted on to be
    connected to the first such host.
[4] Therefore, the conclusion is false, so the condition must also be
    false.

My, I can feel it getting warmer in here already...

--Karl