In synaptic, there's an option in the package manager to mark residual config files/packages for complete removal, and I'm wondering how to do this from the command line. I ran

Code:
sudo deborphan | xargs sudo apt-get purge -y
sudo apt-get autoremove -y
sudo apt-get clean
but some packages still show up in synaptic, so clearly, these commands aren't removing everything. My main laptop runs a command line ubuntu interface with icewm on top, so I primarily use the command line, and I'd like to know how to remove residual config packages from the command line. Maybe something using dpkg -l to search for packages labeled "rc?" Thanks!