[exim] Count all (incl. non local) recipients?

Hi, I was trying and find like $rcpt_count or $recipients_count for full
count of addresses in TO/CC for incoming message. But these $rcpt_count
or $recipients_count are for count envelope recipients (what's
difference?)

I am wonder how we can look at TO:/CC: header which has many recipients
but most are not for local domains? To get overall count of
addresses/recipients at all domains in the TO: and CC: fields? Sorry if
this is FAQ I tried to search mailing list