Author: Nico Erfurth Date: To: Brian Nelson, Exim-users Subject: Re: [Exim] Question about $message_id vs $MESSAGE_ID under exim filters
Brian Nelson wrote: > Hi!
>
> Exim is v3.34 under Solaris 8
>
> I have discovered an oddity here, and don't understand why it is happening.
>
> I have a system filter defined, which causes a pipe of the message out to
> another facility.
>
> The problem is that the $message_id within the filter does not agree with the
> environment variable $MESSAGE_ID passed to the pipe. They are the same, except
> the ENV var has an 'E' prepended to it.
>
> ie
> $message_id = 18gvwl-0006uM-00 (filter)
> $MESSAGE_ID = E18gvwl-0006uM-00 (pipe)
>
> Can someone tell me why this is happening, and if it's supposed to do that? I
> can easily code around it, but it seemed wonky to me. The other env vars all
> appear OK.
Exim appends the E for the Message-Id header, maybe it has something to
do with this:
(from the 3.36 spec.txt)
49.8 The Message-id: header
If an incoming message does not contain a "Message-id:" header, Exim con-
structs one and adds it to the message. The id is constructed from Exim's
internal message id, preceded by the letter E to ensure it starts with a
letter, and followed by @ and the primary host name. Additional information
can be included in this header by setting the "message_id_header_text"
option.
