Re: [Emailcore] Ticket #14: G.7.8. Review different size limits

[John Levine <[e-mail]>]

It appears that Steffen Nurpmeso  <[e-mail]> said:
> |> Speaking of limits, how do we feel about the 1000 octet limit on line
> |> length.  It is my impression that it is often exceeded in HTML text.

>There was that UTF-8 RFC from i think a Microsoft guy who soaped
>this up to say "in modern times a character is the new byte", so
>that this should now be 1000*4, at least for SMTP, ...

That is just wrong.  RFC 6532 specifically says if you're sending unencoded
UTF-8, the limit is still 1000 octets, not 1000 characters.

>Maybe that is a weakness in the original folding algorithm, that
>whitespace at the begin of follow lines is preserved.  Maybe the
>(now) usual "line-continuation by escaping the linefeed with
>reverse solidus" would have been the better approach, ...

That only applies to headers.  The 1000 octet limit applies to the
whole message.  For text we have flowed text which uses a space at
the end of a line as a signal to rewrap.

>Especially since presence of non 7-bit clean data imposes MIME
>encoding, anyway?

Hm.  You might want to investigate the 8BITMIME SMTP extension, defined in
1993 and supported by every MTA I've looked at in this millenium.

R's,
John

PS: I don't feel strongly about lifting the 1000 octet limit but I would like
to understand how widely it's enforced by mail receivers.