Hi i was wondering if it was possible to have a program, ( a dns pointer) to start up on boot, and turn off at log off? I'm using Mandrake 8.1 and i'm using an adsl modem using PPPoE.

Thanks in advance.

The script to start/stop it with should go in
/etc/rc.d/init.d, look in that dir for examples.
Now link that file to the runlevel you would want to run it in, /etc/rc.d/rc3.d for network & multiuser enabled level w/o graphical login, and /etc/rc.d/rc5.d for network & multiuser enabled level w graphical login. Don't forget to prefix it with a capital "S" and a number in the sequence, the "S" means start, and the seqnr is the time it's started at IMO the number should be higher than "networking".
Now add a link to /etc/rc.d/rc0 and /etc/rc.d/rc6, respectively shutdown and reboot levels, prefix it with a capital "K" for kill and a number in the sequence.

*If you don't want to go tru this you could add it to your rc.local to start it.