How to Check Installed Software in Ubuntu Terminal

How to check installed software in Ubuntu terminal? Here is the command to check installed packages in Linux.

On Ubuntu, you can use apt command to list manually installed packages by date or show apt-get list available packages to check recently installed packages in Linux.

Using apt command with argument list is somewhat similar to dpkg-query –list in that it can display a list of packages satisfying certain criteria. It supports patterns for matching package names as well as options to list installed (–installed), upgradeable (–upgradeable) or all available (–all-versions) versions.

The syntax is:

apt list {package-name-here}

If you wish to see the version of installed firefox package, run the following command:

apt list firefox

Using apt-cache Command

apt-cache performs a variety of operations on APT’s package cache. apt-cache does not manipulate the state of the system but does provide operations to search and generate interesting output from the package metadata. The metadata is acquired and updated via the ‘update’ command of e.g. apt-get, so that it can be outdated if the last update is too long ago, but in exchange apt-cache works independently of the availability of the configured sources (e.g. offline).

apt-cache command options to use to check version of installed packages:

  1. showpkg pkg… : showpkg displays information about the packages listed on the command line. Remaining arguments are package names. The available versions and reverse dependencies of each package listed are listed, as well as forward dependencies for each version.
  2. policy [pkg…] : policy is meant to help debug issues relating to the preferences file. With no arguments it will print out the priorities of each source. Otherwise it prints out detailed information about the priority selection of the named package.
  3. madison pkg…: apt-cache’s madison command attempts to mimic the output format and a subset of the functionality of the Debian archive management tool, madison. It displays available versions of a package in a tabular format. Unlike the original madison, it can only display information for the architecture for which APT has retrieved package lists (APT::Architecture).

The syntax is:

apt-cache policy {package}

OR

apt-cache madison {package}

If you wish to see the version of installed firefox package, run the following command:

apt-cache policy firefox

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