The router advertisement daemon (radvd) is run by Linux or BSD systems
acting as IPv6 routers. It sends Router Advertisement messages,
specified by RFC 2461, to a local Ethernet LAN periodically and
when requested by a node sending a Router Solicitation message.
These messages are required for IPv6 stateless autoconfiguration.

Radvd is dependent upon IPv6 support in the Linux kernel; this comes
enabled by default with Slackware 14's generic and huge kernels.
To enable IPv6 support manually, you must set the following entry in
your custom kernel's .config file and recompile: CONFIG_IPV6=m

Once the slackware package is installed, edit /etc/radvd.conf to
reflect your current IPv6 configuration. An init script has been
provided at /etc/rc.d/rc.radvd. To have this start upon each boot, add
the following lines to your /etc/rc.d/rc.local file:
  ## Start the radvd daemon:
  if [ -x /etc/rc.d/rc.radvd ]; then
     /etc/rc.d/rc.radvd start
  fi

check is an optional (build-time only) dependency.