On 2017-09-09, Ian Zimmerman <itz@???> wrote: > Can I set an acl_c variable in a non-smtp ACL?
Yes, in any ACL except those called via ${acl expansion from routers or
transports.
> I want to set a variable for the sole purpose of passing it down to a
> delivery agent (as an environment string). The information only makes
> sense for a SMTP received message (and pertains to the connection, so it
> should be acl_c and not acl_m), but I'd like to always set it to
> _something_, for uniformity.
yes, that should work.
another option is checking $sender_host_address
it will be empty for non-smtp origin messages.