Linux: Add existing user to existing group

I seem to need to look this up at least once a month....


usermod -a -G ftp tony # add tony to the ftp group

Install dependencies with dpkg (kinda)

dpkg -i /tmp/package.deb # Try to install package, fail, but generate list of unresolved dependencies
apt-get -f --force-yes --yes install # Resolve generated dependencies
dpkg -i /tmp/package.deb # Install package (with dependencies now met)