Inserting Init script

[Marino Fernandez <mjferna@yahoo.com>]

Once I placed a bash script in /etc/init.d, how do I create a link so it is 
executed during halt (runlevel 0) and reboot (runlevel 6). I tried this:

update-rc.d <myscriptname> start 99 runlvl 0

But I get this error:

expected runlevel [0-9S] (did you forget "." ?)

Thanks.