Does DCC skip attachments?

Vernon Schryver
Tue Sep 9 16:05:37 UTC 2003

> From: Gary Mills [] 

> I had a complaint today from a professor who was e-mailing documents
> from his home address to his work address.  The mail was rejected by
> DCC.  When I looked at the DCC log, I discovered that the mail was
> multipart/alternative with an attachment.  The plain text part was
> empty.  The HTML part was also empty, except for all the font and style
> definitions inserted by his MUA.  These two parts certainly could be
> identical to thousands of other messages, which would cause DCC to
> consider the mail as bulk mail.
> However, the attachment was his own PDF file, and should have been
> unique.  Did DCC skip this part when it was calculating checksums?

Some image types are ignored by some DCC checksums.  That description
of the message implies that it should not have had a Fuz2 checksum,
but the other checksums should have been computed and distinct.  Where
they?  The checksums of a message can be computed by feeding it to
`dccproc -QC`

] From: "Rose, Bobby" <>

] ...
] I just had a similar case this week were I was asked why a blank message
] was rejected.  It was for some mailing that gest sent out everyday and
] if there wasn't anything to report, it was an empty message (except for
] the crazy html template they used).  I posed the question to them, why
] send out an email if there's nothing to report?  That's like the local
] newpaper delivery a paper that just says "no news today"


] Have him switch to plain text and it probably will go thru because the
] plain empty text part would be too smal for DCC to care about and the
] pdf would most like not have been see anywhere.

I'd guess you can't send PDF as straight plaintext because it's not
7-bit ASCII without control characters.  It probably needs 
quoted-printable or base64.  I agree that sending empty alternatives
is a waste.

] DCC rejects if any mime part matches the fuzzies and is over the
] threshold, basically treating each mime type as a separate message.

no, not exactly.

Vernon Schryver

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