Arnt Gulbrandsen wrote:
Ten or eleven years ago I was told (on ietf-smtp?) that I had
misunderstood that stuff, and that it really had to do with RFC
handwaving, not accepting clearly broken input.
The explanation went something like this: "The RFCs sometimes are
readable instead of precise. Say an RFC specifies a maximum line length,
but it's not entirely clear whether CRLF is included in or added to the
specified length. In that case you should accept max-plus-CRLF and send
only max-including-CRLF."
I forget who that was and no longer have any mail older than 1994. Was
he right or wrong?
The original, with some discussion, is in RFC 791, section3.2.
It is referenced, among other places, in RFC 1958, section
3.9. There's more to it than RFC handwaving.