When you want some script to run at debian startup for all users you put its command line with path and parameters inside of /etc/rc.d/rc.local and make /etc/rc.d/rc.local executable once with chmod 755 /etc/rc.d/rc.local. On a reboot that script will run for anyone logging onto the system from any account. The .bashrc in the user's home directory once it gets the path and script name and parameters is already executable and so long as what you add to it is correct all you need do is to reboot the system. In that case though .bashrc has to run for that specific user in order for what you put into .bashrc to run. You don't put .bashrc inside of /etc/rc.d/rc..local those are intended to do separate kinds of work with different granularity of services.
