Re: OT ASCII character question

From: KPJ (kpj@sics.se)
Date: Wed Aug 02 2000 - 15:31:35 MDT


It appears as if altamira <altamira@ecpi.com> wrote:
|
|I would like to send e-mail containing some set theory symbols. Character
|set ISO-8859-3 contains the symbols I need, but can I use this with
|text-only e-mail or would I have to use HTML e-mail?
|
|I'd be most grateful for advice.

Most people don't have ISO-8859-3 fonts on their machines, but at least they
get a message that some characters could not be displayed properly.
OTOH, one can get all the fonts on the Internet.

I currently support ISO-8859-1, US-ASCII, ISO-646-SE, ISO-8859-2,
                    ISO-8859-7, and ISO 2022-JP.

<WARNING LEVEL=VERBOSE>
If you intend to send your e-mail over Internet your e-mail _must_ follow
the Internet rules for e-mail messages.

Terminology
        You use a user agent (UA). It will probably add headers and give the
        e-mail to its local Message Transfer Agent (MTA), which makes sure
        the e-mail follows the Internet rules (hopefully) and sends it the
        next MTA, ... and so on, until the receiver's MTA delivers to the
        recipient, which will read it with some UA.

The Internet rules state:
    If both MTA's agree to support the same 8-bit character set, and the
    channel between them support 8-bit wide connection, they can do so.

    If not, then the e-mail must either
    (a) be in 7-bit US-ASCII only, or
    (b) be converted using MIME.
   
Q: What happens of you don't follow the rules?
A: It depends. I know of all these reaction from MTAs:
   (i) The 8-bit characters came through, and the recipient could
                read it. Success story.

   (ii) The 8-bit characters came through, but the recipient
                could not read all of it, since some character were
                coded with other bit strings. This happens e.g. when
                some Macintosh users send e-mail to this list.
                Minor lossage, but no big deal.

   (iii) The 8-bit characters came through, but the recipient
                could not read any of it, since the sender's character
                set differed totally from the recipient's, Total lossage.

   (iv) Some MTA somewhere on the line zeroed the leftmost bit of
                all characters to 7-bits, so some characters became garbled.
                Minor or major lossage, depending on context.

   (v) Some MTA decided to follow the rules and bounce the message
                since it didn't follow the rules. This happened to some guy
                who send several kilobytes of text in plain English, but
                who happened to have his Swedish adress in the signature
                and it contained one (1) single 8-bit character ("ä").

   (vi) Some MTA will convert the stuff into MIME, and your e-mail
                will end up containing stuff like this:
                     "r=E4sm=F6rg=E5s"

   (vii) Some UAs and/or MTAs will convert it to HTML (ugh!).

</WARNING>



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