[Exim] exim -bm return code

hi.

Does anyone know with what return codes does exim exit when called as:

exim -bm -oMr scanned-ok -f someone@somewhere

(body goes to stdin)

in various situations.

On a heavy-duty mail relay mail is filtered through virus checker which
is implemented as a system filter. The script, being called via pipe: command checks the mail
and if it's ok, injects it back.

The problem is that for some messages this command returns nonzero status.

Given volumes of mail going through the relay, experimenting on it is no option at all.
And on not very loaded systems no such thing happens.

I'm suspecting that exim returns nonzero error code when message can not be delivered immediately.
(whatever that means)

Please list them all.


./lxnt