[Python-3000] should rfc822 accept text io or binary io?

[Bill Janssen]

> > What if you've got a PNG as one of the multipart components?  With a
> > Content-Transfer-Encoding of "binary"?  There's no way to represent that
> > as a string.
> 
> Sure is. Any byte sequence can be interpreted as latin-1.

Last time I looked, Latin-1 didn't cover the octets 0x80 - 0x9F.
Maybe you're thinking of Microsoft codepage 1252?

> > I wonder if we're misunderstanding each other here.  The "mail
> > message" itself is essentially a binary data structure, not a sequence
> > of strings, though many of its fields consist of carefully specified
> > string values.  Is that what you're saying?
> 
> I don't think so - I assume Barry really wants to use strings as the
> data type to represent the internal structure. It works fine for all
> aspects except for the 8bit and binary content-transfer-encodings.

Yep, that's what I'm saying -- doing it that way breaks on certain
content-transfer-encodings.  There's also a problem with line endings;
the mail standards call for an explicit CRLF sequence.

These things really aren't strings.  Few data packets are.

Bill