Checking if email is valid

[D'Arcy Cain]

On 2023-11-02 00:18, AVI GROSS via Python-list wrote:
> Yes, it would be nice if there was a syntax for sending a test message sort
> of like an ACK that is not delivered to the recipient but merely results in
> some status being sent back such as DELIVERABLE or NO SUCH USER or even
> MAILBOX FULL.

It used to do that.  The facility was very quickly turned off.

> I note earlier iterations of email had addressed like
> mach1!mach2!mach3!ihnp4!mach5!mach6!user or even mach1!mach2!user at mach3 and
> I remember tools that analyzed what other machines various machines claimed
> to have a direct connection to and tried to figure out a connection from
> your source to destination, perhaps a shorter one or maybe a less expensive
> one. Hence machines like ihnp4 and various universities that were densely
> connected to others got lots of traffic. In that scenario, validity had
> another meaning.

Yep.  It's called UUCP.  It still exists.  You can even do UUCP over TCP/IP.

-- 
D'Arcy J.M. Cain
System Administrator, Vex.Net
http://www.Vex.Net/ IM:darcy at Vex.Net
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