[ih] Mailing list standards (was: Holly)

[Kenneth Porter]

On 9/3/2021 1:01 PM, Jack Haverty via Internet-history wrote:
> This seems like another example of silo-ization in the mailing 
> functionality of the Internet, in that the techniques for "mailing 
> lists" have never been standardized.   Or if they have, it hasn't been 
> followed uniformly. 

They've been standardized:

https://datatracker.ietf.org/doc/html/rfc5983#section-5

The format of the List-ID header has a defined format and I use that as 
a spam indicator, since some spammers try to use list headers to sneak 
spam past the filters. A correct List-ID looks like a domain name in 
angle brackets and matches this pattern: /<([\w-]+)(\.[\w-]+)+>/