Re: Comments on draft-klensin-net-utf8-06

"Clive D.W. Feather" <clive@demon.net> Thu, 18 October 2007 09:11 UTC

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Date: Thu, 18 Oct 2007 10:11:27 +0100
From: "Clive D.W. Feather" <clive@demon.net>
To: Marcos Sanz/Denic <sanz@denic.de>
Subject: Re: Comments on draft-klensin-net-utf8-06
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Marcos Sanz/Denic said:
> There is a similar contradictory (less restrictive at the beginning and 
> suddenly more restrictive at the end) situation in bullet 3. The first 
> sentence goes
> 
>   [...] control characters (U+0000 to U+001F and U+007F to U+009F) SHOULD 
> generally be avoided
> 
> vs the last sentence
> 
>   the so-called "C1 Controls" (U+0080 through U+009F) MUST NOT appear
[...]

Agreed. In addition, at the end of item 2 of section 2:

OLD TEXT:

The newer control characters IND (U+0084) and NEL
("Next Line", U+0085) might have been used to disambiguate the
various line-ending situations, but, because their use has not
been established on the Internet and many protocols require CRLF,
they SHOULD NOT be used.

SUGGESTED TEXT:

The newer control characters IND (U+0084) and NEL
("Next Line", U+0085) might have been used to disambiguate the
various line-ending situations, but, because their use has not
been established on the Internet, because many protocols require CRLF,
and because they fall within the "C1 Control", they MUST NOT be used.


Nit-pick: right at the end of section 2, NUL should be described as U+0000
and not as X'00' (a notation which isn't well-defined). Or, if you are
trying to distinguish octets from characters, use the RFC 4234 notation of
%x00. Similarly, at the end of appendix B, IAC should be %xFF.

Incidentally, %xFE is also not a problem for UTF-8, and %xF5-FD are
probably not problems.

-- 
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