🚀 go-pugleaf

> / hpfclp:comp.mail.misc / jsdy@hadron.UUCP (Joseph S. D. Yao) /  6:52 am  Apr 28, 1987 /
> In article <600@vixie.UUCP> paul@vixie.UUCP (Paul Vixie Esq) writes:
> >The various standards in place around the net (in RFC form) say: no.
> 
> After the Nth last time this was discussed (*sigh*), I tried to verify
> this for a paper I was writing.  (I'm sorry: the paper is  s t i l l
> being written.)  Various people, including Mark Horton (!), told me
> that they couldn't find where this was said, either.  If this has
> changed, and someone has found the citation, I'd really appreciate
> hearing about it!

Well, you may be right that this is not stated in exactly that form.
However, it can easily be concluded from other statements in RFCs.  Both
RFC-822 and RFC-976 are quite clear on @ precedence (822 because it
doesn't recognize anything else -- 976 because it says so explicitly).
Given that the only possible intent of tacking on myhost! to a From:
line is to keep the address replyable, and @ precedence in the From:
line guarantees that the address won't be replyable, adding myhost!
to a From: line that already has a @ is clearly wrong.  I believe the
BNF in RFC-822 clearly requires one and only one @ in the address,
so this makes prepending myhost! always wrong.

Put another way, there are three possible situations with From: lines:

1) One exists with a domain address
2) One exists with a UUCP address
3) One doesn't exist yet

In case 1, it is clearly wrong to prepend myhost! as stated above.  Case
2 is common but violates RFC-822 because there is no @.  Case 3 requires
that the address be constructed with an @ in the From: line (only 
the From_ line may have the myhost! in it).  So, in no case is it
legal (by extrapolation from the RFCs) to prepend myhost! to a From:
line.


John Diamant
SCO				UUCP:  {hplabs,hpfcla}!hpfclp!diamant
Hewlett Packard Co.		ARPA Internet: diamant%hpfclp@hplabs.HP.COM
Fort Collins, CO