zshrc

su () {
  checksu=0
  for flags in $*; do
    if [[ $flags == "-" ]]; then
      checksu=1
    fi
  done
  if [[ $checksu == 0 ]]; then
    echo "Use 'su -', Luke"
    /usr/bin/su - $*
  else
    /usr/bin/su $*
  fi
}