Phil Pennock <exim-users@???> writes:
> On 2008-08-22 at 16:10 +0200, Ferenc Wagner wrote:
>
>> Jeremy Harris <jgh@???> writes:
>>
>>> Ferenc Wagner wrote:
>>>
>>>> For tracking email, I'd like to log the message-id generated by Exim
>>>> for mail submitted by a local process. How could I achieve this?
>>>
>>> Look in the docs at http://exim.org for "log_message" and "$message_id"
>>
>> OK, I cooked up this:
>>
>> acl_not_smtp = acl_log_message_id
>> begin acl
>> acl_log_message_id:
>> warn log_message = Generated message id: $message_id
>> accept
>>
>> And mainlog says:
>>
>> 2008-08-22 15:53:12 1KWX4i-0002NF-0C U=wferi Warning: Generated message id: 1KWX4i-0002NF-0C
>> 2008-08-22 15:53:12 1KWX4i-0002NF-0C <= wferi@mydomain U=wferi P=local S=341
>>
>> Which makes me feel stupid. Apparently each log line is prefixed with
>> the message id, sort of. Because in the received mail I find:
>>
>> Message-Id: <E1KWX4i-0002NF-0C@mydomain>
>>
>> Where does the E prefix come from?
>
> There are two different "message ids" here.
>
> There's $message_exim_id, which used to be called $message_id;
> $message_id still works, for backwards compatibility, but the name is
> confusing, which is why it became $message_exim_id. And there's the
> "Message-Id:" header value.
>
> Exim always logs its internal $message_exim_id for mails. This is the
> "handle" used to identify all mails passing through Exim; things like
> files on the spool have names based on this value, it's put into the
> "Received:" header, etc.
>
> If there is not already a Message-Id: header, then Exim creates one. By
> default it uses E${message_exim_id}@$primary_hostname to construct it.
> You can change the "domain" part with message_id_header_domain and you
> can add something extra just before the @ with message_id_header_text.
>
> The 'E' prefix is there for the "external" form of the internal
> $message_exim_id; I don't know why, but I'll guess that it's best if
> the Message-Id *always* starts with a letter [*] and that it sometimes
> helps to have a visual marker so you can tell, when people cut&paste
> information, where the data is coming from. I've no idea if it stands
> for 'Exim' or 'External' or both.
>
> -Phil
>
> [*] "best" not because any standard requires it but to minimise problems
> with buggy software which puts in bogus checks. This is purely
> hypothesis.
Hi Phil,
Thank you very much for the detailed explanation!
--
Regards,
Feri.
