[Sca-cooks] How Mail Works

[Avraham haRofeh of Sudentur]

>>>I'm not sending attachments.  I may be replying to someone else's e-mail,
but if I post, say, a recipe, I usually copy and paste it from my word
files.  Is it possible that "attachments" are actually "links"?  One message
I checked that said it came with an attachment had only a link.<<<


It depends on your mail program. So many of us are using HTML-aware Windows
(or Mac) mail programs that we rarely have any idea what's going on behind
the scenes.

When you transmit a plain-text mail message, your mailer attaches the
appropriate headers to indicate source, destination and subject, then adds a
tail tag which says "End of message". When you send a non-plain-text
message, a line like this is added:

************
This is a multi-part message in MIME format.

--===============74256959438920611==
Content-Type: multipart/alternative;
 boundary="----=_NextPart_000_0AE5_01C341AE.78BB4680"
************

Depending on what the "Content-Type" segment says, your software may or may
not interpret this as an attachment. Binary attachments like pictures and
sounds are encoded, most often using the UUCode system. Most email software,
especially on older and non-graphic-oriented OS'es, is only 7-bit, but
binaries are 8-bit, so you need to convert them. That's why some systems
convert non-standard characters to odd codes, often starting with an = -
it's an indication that there was an 8-bit character there that the software
couldn't handle.

Some programs drop in that "multi-part message" boundary any time there's a
reply, so all the old messages become attachments. Some packages put the
boundary in for links, as Brekke says, so that the URL becomes an
"attachment" which can be "opened" directly into your browser. Many packages
will allow you to generate HTMLized mail, then put the plain ASCII text into
one boundary zone, and the HTML into another. If your software can
distinguish between them, it will ignore the one you can't/don't want to
use. If not, you will see both.

Since there's little standardization about how, when and why these boundary
tags are added, no software package can really handle them all. For all the
complaints and security holes, Outlook/Outlook Express probably does the
best job of managing them. IMHO, of course, YMMV.

Avraham

*******************************************************
Reb Avraham haRofeh of Sudentur
     (mka Randy Goldberg MD)
RandomTag: Love is definitely not blind!