.PS
# in and out channels of masqmail

linewid = 1.5


A: box "masqmail" wid 1.5*boxwid ht 1.5*boxht

line <- left from 0.5<A.w,A.nw> "remote (SMTP)" above
line <- left from 0.5<A.w,A.sw> "local (stdin)" above

line -> right from 0.7<A.e,A.ne> "remote (SMTP)" above
line -> right from A.e "local (pipe)" above
box "command" wid boxwid ht 0.5*boxht
line  right from 0.7<A.e,A.se> "local (delivery)" above
line down .1
move 0.5*moveht
C: box invis "mailboxes" ht 0.3

arrow from last line.end to 0.2<C.nw,C.ne>
arrow from last line.end to 0.4<C.nw,C.ne>
arrow from last line.end to 0.6<C.nw,C.ne>
arrow from last line.end to 0.8<C.nw,C.ne>

line <- up from A.n
box invis ht 0.3 "online state"

.PE