dpkg

dpkg is a package manager for Debian based systems. It can install, remove, and build packages, but unlike other package management system's it can not automatically download and install packages and their dependencies. This section covers using dpkg to manage locally installed packages:

  • To list all packages installed on the system, from a terminal prompt enter:

    dpkg -l
    
  • Depending on the amount of packages on your system, this can generate a large amount of output. Pipe the output through grep to see if a specific package is installed:

    dpkg -l | grep apache2
    

    Replace apache2 with any package name, part of a package name, or other regular expression.

  • To list the files installed by a package, in this case the ufw package, enter:

    dpkg -L ufw
    
  • If you are not sure which package installed a file, dpkg -S may be able to tell you. For example:

    dpkg -S /etc/host.conf 
    base-files: /etc/host.conf
    

    The output shows that the /etc/host.conf belongs to the base-files package.

    [Nota]

    Many files are automatically generated during the package install process, and even though they are on the filesystem dpkg -S may not know which package they belong to.

  • You can install a local .deb file by entering:

    sudo dpkg -i zip_2.32-1_i386.deb
    

    Change zip_2.32-1_i386.deb to the actual file name of the local .deb file.

  • Uninstalling a package can be accomplished by:

    sudo dpkg -r zip
    
    [Atenció]

    Uninstalling packages using dpkg, in most cases, is NOT recommended. It is better to use a package manager that handles dependencies, to ensure that the system is in a consistent state. For example using dpkg -r you can remove the zip package, but any packages that depend on it will still be installed and may no longer function correctly.

For more dpkg options see the man page: man dpkg.