It'd be nice to be able to turn pppd debugging on and have those
messages routed to diald-<iface>.ctl, but I don't think it would be a good
idea to route all daemon.debug messages to diald-<iface>.ctl so a filter like
the one in diald-connect is called for.

Man page for package.

Man page for start-dctrl.

Check to see that a diald daemon is not already started to manage an
interface.
