Author: Sahil Suri

Introduction In our earlier articles on package management for Debian bases distributions, we’ve covered dpkg, apt-get, and apt-cache tools. In this article, we will cover the apt tool for managing packages on our Ubuntu 16.04 system. The command line options for apt are very similar to those available with apt-get and apt-cache because apt encompasses features of both these tools into one package management tool. Apt is a front-end tool which works with dpkg in the background to maintain software on the system. To interact with the apt package manager, we use the apt command along with the appropriate options. We’ll now take you through some examples to help understand how we use the apt package manager. Example 1: Update local cache The system queries online remote and local repositories and maintains a cache of information about packages available in these repositories. This cache could be regarded as an index of available packages in the online repositories. The names and URLs of these online repositories are maintained in /etc/apt/sources.list file. Given below is a snippet from the file on my local system: root@linuxnix:~# cat /etc/apt/sources.list | grep -Ev '^#|^$|ec2' deb http://security.ubuntu.com/ubuntu xenial-security main restricted deb-src http://security.ubuntu.com/ubuntu xenial-security main restricted deb http://security.ubuntu.com/ubuntu xenial-security universe deb-src http://security.ubuntu.com/ubuntu xenial-security universe deb http://security.ubuntu.com/ubuntu xenial-security multiverse deb-src http://security.ubuntu.com/ubuntu xenial-security multiverse We can update that cache using the apt update command. Periodically updating the cache...