From: Charles Lindsey (chl@clw.cs.man.ac.uk)
Date: Mon Apr 15 2002 - 04:10:32 CDT
In <Zwf0$QDGDot8EwAV@on-the-train.demon.co.uk> "Clive D. W. Feather" <clive@on-the-train.demon.co.uk> writes:
>>4a. Leave it as it is.
>>
>>4b. Disallow parameters in those address-list headers. That would eliminate
>> Complaints-To
>> Reply-To
>> Mail-Copies-To
>>(though you might exclude Complaints-To and Mail-Copies-To on the
>>grounds that they are "ours", parsing problems or not)
>I would prefer 4b, but can live with 4a. If you do 4b, you do it for all
>three headers, because it eliminates the parsing ambiguity.
Actually, if you are doing 4b, you may as well do 4c (adds From to the
bunch). That can be rationalised on the grounds that user agents are going
to take one of those headers, check for the absence of special cases like
"nobody" and "poster", replace the header-name by "To" or "Cc", and then
chuck it at some mail system without further checks. If we adopted 4c, I
would add a NOTE on those lines.
So far, I hear 3 people arguing for leave-it-as-is, or go as far as I just
suggested, plus a couple who are opposed to the whole parameter concept
anyway. We need to hear more opinions but, in the absence of further
comment, my inclination is to go for 4c, as just described.
>> UTF8-xtra-2-head = %xC2-DF
>> UTF8-xtra-3-head = %xE0 %xA0-BF / %xE1-EC %x80-BF /
>> %xED %x80-9F / %xEE-EF %x80-BF
>> UTF8-xtra-4-head = %xF0 %x90-BF / %xF1-F7 %x80-BF
>> UTF8-xtra-5-head = %xF8 %x88-BF / %xF9-FB %x80-BF
>> UTF8-xtra-6-head = %xFC %x84-BF / %xFD %x80-BF
>> UTF8-xtra-char = UTF8-xtra-2-head 1( UTF8-xtra-tail ) /
>> UTF8-xtra-3-head 1( UTF8-xtra-tail ) /
>> UTF8-xtra-4-head 2( UTF8-xtra-tail ) /
>> UTF8-xtra-5-head 3( UTF8-xtra-tail ) /
>> UTF8-xtra-6-head 4( UTF8-xtra-tail )
>> UTF8-xtra-tail = %x80-BF
>You may or may not recall a discussion on the NNTP list about changing
>this, in particular by removing the -5- and -6- cases (Unicode says
>these will never happen, as 0x10FFFF characters are enough for anyone).
>Do you recall if a consensus was reached? The two ought to be
>consistent.
No, I don't recall that, but I shall check on the NNTP Archive.
I have no strong views on the -5 and -6 cases. They are legal (for
encoding 32 bit character sets) according to the UTF-8 specification, but
nobody is seriously contenplating 32 bit charsets, and Unicode has
invented its "surrogate" hack to avoid using them.
-- Charles H. Lindsey ---------At Home, doing my own thing------------------------ Tel: +44 161 436 6131 Fax: +44 161 436 6133 Web: http://www.cs.man.ac.uk/~chl Email: chl@clw.cs.man.ac.uk Snail: 5 Clerewood Ave, CHEADLE, SK8 3JU, U.K. PGP: 2C15F1A9 Fingerprint: 73 6D C2 51 93 A0 01 E7 65 E8 64 7E 14 A4 AB A5