Re: Comments on draft-resnick-2822upd-02.txt

In <[email protected]> SM <[email protected]> writes:

>At 14:44 15-08-2007, Charles Lindsey wrote:
>> >2.1.1.  Line Length Limits
>> >
>> >   There are two limits that this specification places on the number of
>> >   characters in a line.  Each line of characters MUST be no more than
>> >   998 characters, and SHOULD be no more than 78 characters, excluding
>> >   the CRLF.
>>
>>Can we de-emphasise that SHOULD, and make it clear that this is a matter
>>of good practice (in the sense of BCP) rather than a normative feature?
>>Perhaps s/SHOULD/should/? Too many agents have used this as an excuse to
>>rewrite lines en route (maybe there should be a SHOULD NOT for that).

>I read that as more than a BCP.  Quoting a message from the 2822 era:

>   "The 78 character recommendation is due to limitations in many
>    implementations which display these messages which may truncate display
>    of more than 78 characters per line. Of course, even though these
>    limitations are put on messages, interpreters of messages would do well
>    to handle an arbitrarily large number of characters in a line, including
>    for display, for robustness' sake."

>>Where did that '78' come from? I am aware of lots of systems that do
>>horrid things such as you mention if there are 80 characters in a line,
>>but I am aware of none where problems arise with exactly 79. In other fora
>>where I have seen this discussed, the consensus was that exceeding '79'
>>was the signal for troubles to start.

>There are 80 characters per line on a text display.  There may be a 
>one character border on the left and right hand side.  That leaves 
>you with 78 characters.  Some (old) displays do not wrap a long 
>line.  Although it may sound obsolete in this day and age, some 
>messages may be sent directly to a printer which may have the same line limit.

I have never seen a text display with a one character border at the left,
though I have seen many with such a border at the right (and which causes
strange wrappings if you try to use it).

-- 
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