trewrite - plan9port - [fork] Plan 9 from user space
  HTML git clone git://src.adamsgaard.dk/plan9port
   DIR Log
   DIR Files
   DIR Refs
   DIR README
   DIR LICENSE
       ---
       trewrite (668B)
       ---
            1 # case conversion for postmaster
            2 pOsTmAsTeR        alias                postmaster
            3 
            4 # local mail
            5 [^!@]+                translate        "upas/aliasmail '&'"
            6 local!(.*)        >>                $PLAN9/mail/box/\1/mbox
            7 \l!(.*)                alias                \1
            8 (helix|helix.bell-labs.com)!(.*)        alias                \2
            9 
           10 # we can be just as complicated as BSD sendmail...
           11 # convert source domain address to a chain a@b@c@d...
           12 @([^@!,]*):([^!@]*)@([^!]*)        alias        \2@\3@\1
           13 @([^@!]*),([^!@,]*):([^!@]*)@([^!]*)        alias        @\1:\3@\4@\2
           14 
           15 # convert a chain a@b@c@d... to ...d!c!b!a
           16 ([^@]+)@([^@]+)@(.+)        alias        \2!\1@\3
           17 ([^@]+)@([^@]+)                alias        \2!\1
           18 
           19 # /mail/lib/remotemail will take care of gating to systems we don't know
           20 ([^!]*)!(.*)                 |                 "$PLAN9/mail/lib/qmail '\s' 'net!\1'" "'\2'"