Not really familiar with sendmail as a full-on MTA, but I need to get a list of email addresses.
I've Googled around, and from that, I've checked
/etc/mail/aliases (there's some in there, but this is mainly used for Blackberry forwarding as it seems incomplete) and
virtusertable (empty) and from what I can tell, mail is delivered to local users. However, there's a lot of local UNIX users in there and by the date modified, I'm guessing a bunch are old.
Surely there must be another localpart (email address) to local user mapping somewhere or a better way to tell what email addresses are active (or at least, functioning; I can handle some inactive ones as missing some would be worse, obviously).