[Retros] attachments in messages

[Otto Janko]

Dear Andrew,

I did a little invetigation on this issue and came to the following
conclusion (sorry, there is a little tech speak, but without that it's
impossible to explain the behaviour):

Clearly, this attachment is added by the mailing list software, in this case
Mailman. Mailman adds these four lines to each and every mail. Whether these
lines become part of the mail body or become an attachment depends on the
message format choosen by the mail sender.

For plain text messages, this is "Content-Type: text/plain", the four lines
are simply added at the end of the text body.

For all other messages, e.g. "Content-Type: text/html", the whole message is
converted to "Content-Type: multipart/mixed". The original message becomes
the first part (text/html) and the four lines added by Mailman become the
second (text/plain). A mail client usually displays the first part as mail
body and all other parts as attachment (at least as long as the first part
is of a MIME type which the mail client understands).

The obvious reason is that it is not possible to simply add text lines to
any other content than text/plain. For text/html, for example, these four
lines would be added below the "</html>" tag and most likely never been
shown by the mail client. 

What can be done? 

The senders of a message to the mailing list may refrain from sending
messages other than text/plain. Most of the messages are already text/plain,
but a few are not. I checked a few of the text/html and text/rtf messages
and did not find any reason why these messages could not be sent text/plain
(no text formatting is used, no coloring, etc.). Maybe it's simply the fact
that the mail client chooses text/html per default for new messages. Note
that usage of a Web front-end usually produces text/html messages, not
text/plain messages.

I could not find an appropriate Mailman option to switch off the four lines
(if there is such an option then it is well hidden). 

I can configure Mailman in a way that only text/plain messages are accepted.
But this would make it impossible to use e.g. bold, italics or coloring if
it is really needed.

Best Regards,

- Otto Janko [mailto:otto at janko.at] [http://www.janko.at]
-- Those who desire to give up freedom in order to gain security, 
- will not have, nor do they deserve, either one." [Benjamin Franklin]




> -----Original Message-----

> From: retros-bounces at janko.at 

> [mailto:retros-bounces at janko.at] On Behalf Of andrew buchanan

> Sent: Thursday, January 18, 2007 4:18 AM

> To: Retros Mailing List

> Subject: [Retros] attachments in messages

> 

> Admin issue here.

> 

> I have noticed that sometimes the messages that I get on this mailing

> list have got an attachment, which when I open it has got very dull

> contents, namely the following 4 lines:

> 

> >_______________________________________________

> >Retros mailing list

> >Retros at janko.at

> >http://www.pairlist.net/mailman/listinfo/retros

> 

> Because of the attachment, this kind of message is much more likely to

> end up in my spam folder.

> 

> Over the last few months, there has been an upsurge in worldwide spam,

> and although I normally try to quickly scan the spam folder, I can't

> guarantee that I spot messages there.

> 

> Otto: please what triggers the inclusion of this attachment, and you

> explain how we can all avoid it.

> 

> Thanks so much,

> Andrew. 

> _______________________________________________

> Retros mailing list

> Retros at janko.at

> http://www.pairlist.net/mailman/listinfo/retros

>