How to Remove Packages Using the Command Line in Linux.
Apt
The apt command is a powerful command-line tool, which works with Ubuntu’s Advanced Packaging Tool (APT) performing such functions as installing new software packages, upgrading existing software packages, updating the package, upgrading the entire Ubuntu system, and even removing packages.
List installed packages
You can list all installed packages by using the dpkg --list, apt list --installed command or grep with whatever your memory serves you.
dpkg --list
$ sudo dpkg --list
Output
Desired=Unknown/Install/Remove/Purge/Hold
| Status=Not/Inst/Conf-files/Unpacked/halF-conf/Half-inst/trig-aWait/Trig-pend
|/ Err?=(none)/Reinst-required (Status,Err: uppercase=bad)
||/ Name Version Architecture Description
+++-=====================================-==================================-============-===============================================================================
ii adduser 3.118ubuntu5 all add and remove users and groups
ii amd64-microcode 3.20191218.1ubuntu2 amd64 Processor microcode firmware for AMD CPUs
ii apparmor 3.0.3-0ubuntu1 amd64 user-space parser utility for AppArmor
ii apport 2.20.11-0ubuntu71.1 all automatically generate crash reports for debugging
...
..
.
ii distro-info-data 0.51ubuntu1.1 all information about the distributions' releases (data files)
ii dmeventd 2:1.02.175-2.1ubuntu3 amd64 Linux Kernel Device Mapper event daemon
ii dmidecode 3.3-3 amd64 SMBIOS/DMI table decoder
ii dmsetup 2:1.02.175-2.1ubuntu3 amd64 Linux Kernel Device Mapper userspace library
ii dosfstools 4.2-1build2 amd64 utilities for making and checking MS-DOS FAT filesystems
ii dpkg 1.20.9ubuntu2 amd64 Debian package management system
ii duf <<< 0.6.2-1 amd64 Disk Usage/Free Utility
ii e2fsprogs 1.46.3-1ubuntu3 amd64 ext2/ext3/ext4 file system utilities
ii eatmydata 105-9build2 all Library and utilities designed to disable fsync and friendsapt list --installed
$ sudo apt list --installed
Output
adduser/impish,now 3.118ubuntu5 all [installed,automatic]
amd64-microcode/impish,now 3.20191218.1ubuntu2 amd64 [installed,automatic]
apparmor/impish,now 3.0.3-0ubuntu1 amd64 [installed,automatic]
apport-symptoms/impish,now 0.24 all [installed,automatic]
apport/impish-updates,now 2.20.11-0ubuntu71.1 all [installed,automatic]
...
..
.
distro-info-data/impish-updates,impish-security,now 0.51ubuntu1.1 all [installed,automatic]
distro-info/impish,now 1.0 amd64 [installed,automatic]
dmeventd/impish,now 2:1.02.175-2.1ubuntu3 amd64 [installed,automatic]
dmidecode/impish,now 3.3-3 amd64 [installed,automatic]
dmsetup/impish,now 2:1.02.175-2.1ubuntu3 amd64 [installed,automatic]
dosfstools/impish,now 4.2-1build2 amd64 [installed,automatic]
dpkg/impish,now 1.20.9ubuntu2 amd64 [installed,automatic]
duf/impish,now 0.6.2-1 amd64 [installed] <<<
e2fsprogs/impish,now 1.46.3-1ubuntu3 amd64 [installed,automatic]
eatmydata/impish,now 105-9build2 all [installed,automatic]
grep
The grep command will show all the installed packages that have the string 'du' in their name anywhere, not just the beginning.
$ sudo apt list -- installed | grep -i du
Output
WARNING: apt does not have a stable CLI interface. Use with caution in scripts.
adduser/impish,now 3.118ubuntu5 all [installed,automatic]
bsdutils/impish-updates,impish-security,now 1:2.36.1-8ubuntu2.2 amd64 [installed]
duf/impish,now 0.6.2-1 amd64 [installed] <<<
findutils/impish,now 4.8.0-1ubuntu2 amd64 [installed]
libmodule-find-perl/impish,now 0.15-1 all [installed,automatic]
libmodule-scandeps-perl/impish,now 1.30-1 all [installed,automatic]
libpam-modules-bin/impish,now 1.3.1-5ubuntu11 amd64 [installed,automatic]
libpam-modules/impish,now 1.3.1-5ubuntu11 amd64 [installed,automatic]
...
..
.
Remove a Package(s)
1. Using apt purge
$ sudo apt remove <package-name>
'remove' only gets rid of the package leaving any configuration files untouched.
Tip
Multiple Packages: You may specify multiple packages to be installed or removed, separated by spaces.
2. Using apt purge
$ sudo apt purge <package-name>
'purge' not only removes the package but also removes all configuration files. This is done on purpose since the same software will utilize the same configuration files if you reinstall it.
3. Using apt autoremove
Installed Linux apps rely on additional packages to work. When you remove software, it's possible that certain packages that the uninstalled application relied on are no longer needed. Use the 'autoremove' command to get rid of any unwanted packages.
$ sudo apt autoremove <package-name>
4. Combining both commands
You can combine the two commands for removing a program and removing dependencies that are no longer needed.
$ sudo apt purge --auto-remove <package-name>
5. Clean up
$ sudo apt clean
The above command removes downloaded archive files from the aptitude cache in '/var/cache/apt/archives'. When you install a program, the package file is downloaded and stored in that directory. The files in the directory aren't required to be kept. The only disadvantage of uninstalling them is that if you desire to reinstall any of those programs, you will have to download the packages again.
Little weird Secret 😜
Both 'purge' and 'remove', as opposed to their primary duty, may be used to INSTALL packages. This is accomplished by adding a '+' to the end of the package name.
$ sudo apt <remove/purge> <package-name>+As we have seen earlier, uninstalling programs via CLI is a process that is both fundamental and crucial. This also contributes to the security and stability of your Linux system.