qmail-conf is a collection of tools for setting up various qmail services.
They are like *-conf programs in djbdns. 

With qmail-conf, for example, setting up a minimal SMTP service takes
the following four steps:

qmail-smtpd-conf qmaild qmaill /var/qmail/service/smtpd
cd /var/qmail/service/smtpd
make
ln -s /var/qmail/service/smtpd /service 
qmail-conf assumes that (recent versions of) daemontools and ucspi-tcp have
already been installed. It also assumes that svscan is already running.

qmail-conf tries to provide reasonable defaults: it avoids DNS reverse lookups;
it avoids IDENT lookups; it lets TCP connection attempts be logged with
multilog; and for POP3 and QMQP, connection attempts are denied unless you
explicitly authorize and for POP3 and QMQP, connection attempts are denied
unless you explicitly authorize and for POP3 and QMQP, connection attempts
are denied unless you explicitly authorize and for POP3 and QMQP,
connection attempts are denied unless you explicitly authorize your clients.