On 12/3/18 6:08 PM, RW wrote:
I think, as the name suggests, that was multiple "bangs" (a bang being the character "!"),
I was implying routing like UUCP bang paths. As in host 1 via host 2 via host 3.
Check out (source) route addressing in RFC 822 §§ 6.1 (Address Specification) Syntax, 6.2.7 - Explicit Path Specification, and C.5.4 - Route Addressing. § C.5.4 makes back reference to RFC 733 and I found info in § IV.A.1.f.
RFC 822 deprecated the source route addressing in 1982. But it was officially defined.
I think an @ can be a part of a local-part, but it is really about usage.
As far as I know, (other than LONG deprecated source routing) the @ character is a reserved special character and can't be used used as part of the local part.
I wonder if there is a point to it? Is there a client that ends-up displaying something misleading?
The reason for the multiple @ signs in an actual email address (not human friendly name / description) was to route email through servers. Similar to the way that UUCP bang paths work. According to my skim of RFC 733, it was primarily used for routing through disparate networks with few points of interconnection.
Route Addressing may be deprecated, but it seems to still work. I just sent a message from my mail server (MSA), to my backup MX, back to my main MTA (same machine as the MSA) via route addressing and it worked. The syntax is a bit odd, but it does still work.
-- Grant. . . . unix || die
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