Check if an apt-get package is installed and then install it if it's not on Linux

Question

I\'m working on a Ubuntu system and currently this is what I\'m doing:

if ! which command > /dev/null; then
   echo -e \"Command not found! Install? (y/n)         


        

Answer 1

In Bash:

PKG="emacs"
dpkg-query -l $PKG > /dev/null || sudo apt install $PKG

Note that you can have a string with several packages in PKG.