1. List packages matching given pattern

dpkg -l package-name-pattern

Dpkg is the Ubuntu package manager dpkg is a medium-level tool to install, build, remove and manage Ubuntu packages. The primary and more user-friendly front-end for dpkg is dselect.dpkg itself is controlled entirely via command line parameters,which consist of exactly one action and zero or more options. The action-parameter tells dpkg what to do and options control the behavior of the action in some way.

Now we will see all the available commands for dpkg with examples

2. Install a package

Syntax: dpkg -i <.deb file name>

Example: dpkg -i avg71flm_r28-1_i386.deb

3. Install all packages recursively from a directory

Syntax: dpkg -R

Example: dpkg -R /usr/local/src

4. Unpack the package, but don’t configure it.

Syntax: dpkg —unpack package_file

If you use -R option is specified, package_file must refer to a directory instead.

Example: dpkg —unpack avg71flm_r28-1_i386.deb

5. Reconfigure an unpacked package

Syntax: dpkg —configure package

If -a is given instead of package, all unpacked but uncon-figured packages are configured.

Example: dpkg —configure avg71flm_r28-1_i386.deb

6. Remove an installed package except configuration files

Syntax: dpkg -r

Example: dpkg -r avg71flm_r28-1_i386.deb

7. Remove an installed package including configuration files

Syntax:

dpkg -P

If you use -a is given instead of a package name, then all packages unpacked, but marked to be removed or purged in file /var/lib/dpkg/status, are removed or purged, respectively.

Example: dpkg -P avg71flm

8. Replace available packages info

Syntax: dpkg —update-avail <Packages-file>

With this option old information is replaced with the information in the Packages-file.

9. Merge with info from file

Syntax: dpkg —merge-avail <Packages-file>

With this option old informa-tion is combined with information from Packages-file.

The Packages-file distributed with Debian is simply named Packages.dpkg keeps its record of available packages in /var/lib/dpkg/available.

10. Update dpkg and dselect’s idea of which packages are available with information from the package pack-age_file.

Syntax: dpkg -A package_file

11. Forget about uninstalled unavailable packages.

Syntax: dpkg —forget-old-unavail

12. Erase the existing information about what packages are available.

Syntax: dpkg —clear-avail

13. Searches for packages that have been installed only partially on your system.

Syntax: dpkg -C

14. Compare Package versions version numbers

Syntax: dpkg —compare-versions ver1 op ver2

15. Display a brief help message.

Syntax: dpkg —help

16. Display dpkg licence.

Syntax: dpkg —licence (or. dpkg —license

17. Display dpkg version information.

Syntax: dpkg —version

18. Build a deb package.

Syntax: dpkg -b directory [filename]

19. List contents of a deb package.

Syntax: dpkg -c filename

20. Show information about a package.

Syntax: dpkg -I filename [control-file]

21. List packages matching given pattern.

Syntax: dpkg -l package-name-pattern

Example: dpkg -l vim

22. List all installed packages, along with package version and short description

Syntax: dpkg -l

23. Report status of specified package.

Syntax: dpkg -s package-name

Example: dpkg -s ssh

24. List files installed to your system from package.

Syntax: dpkg -L package-Name

Example: dpkg -L nagios2

25. Search for a filename from installed packages.

Syntax: dpkg -S filename-search-pattern

Example: dpkg -S /sbin/ifconfig

26. Display details about package

Syntax: dpkg -p package-name

Example: dpkg -p nagios2