This service starts a session
dbus-daemon.
It is important to set the environment variable
DBUS_SESSION_BUS_ADDRESS,
so other services depending on dbus-daemon can find it.
The DBUS_SESSION_BUS_ADDRESS environment variable
should be set at
${HOME}/@userconfdir@/@USERTREE@/env/DBUS_SESSION_BUS_ADDRESS,
by writing the address into this file
(see configuration directory).
It is recomended to set
${HOME}/@userconfdir@/@USERTREE@/env/DBUS_SESSION_BUS_ADDRESS,
to
@tmpusdir@/@usrrundir@/@USER@/@USERTREE@/session-bus
(see runtime directory).