[exim] Behaviour of 'message' after a discard verb in the ac…

In the acl_smtp_mime ACL section of my Exim config file I have an ACL to
deny foreign language e-mails.

The following worked fine:

        deny    condition       =       ${if match {${lc:$mime_charset}}
\

{\N(iso-2022-jp|windows-1251|big5|big-5)\N}}
                message         =       E-mail from Internet not in
english ($mime_charset), F=$sender_address - deny!

with the message being written to the mainlog file.

I then changed 'deny' to 'discard' as follows:

        discard condition       =       ${if match {${lc:$mime_charset}}
\

{\N(iso-2022-jp|windows-1251|big5|big-5)\N}}
                message         =       E-mail from Internet not in
english ($mime_charset), F=$sender_address - discard!

and found that, although the e-mails seemed to be discarded OK, there
was no message in the mainlog file.


I then experimented and changed 'message' to 'logwrite' as follows:

        discard condition       =       ${if match {${lc:$mime_charset}}
\

{\N(iso-2022-jp|windows-1251|big5|big-5)\N}}
                logwrite        =       E-mail from Internet not in
english ($mime_charset), F=$sender_address - discard!

and found that the message was then written OK to the mainlog file.


Is this something stupid I am doing or a bug?



Paul McIlfatrick