Linux apt remove purge

• You’re compiling a program and, all of a sudden, there’s an error because it needs a file you don’t have. The program auto-apt asks you to install packages if they’re needed, stopping the relevant process and continuing once the package is installed.

Maintenance commands

The same as the above, except add the «smart upgrade» checkbox. It tells APT to use «smart» conflict resolution system, and it will attempt to upgrade the most important packages at the expense of less important ones if necessary.

«apt-get dist-upgrade» does not upgrade from a previous version of Ubuntu. For more information of upgrading from a previous version of Ubuntu see http://www.ubuntu.com/getubuntu/upgrading .

du -sh /var/cache/apt/archives

Reconfigure the named package. With many packages, you’ll be prompted with some configuration questions you may not have known were there.

• For example:

dpkg-reconfigure fontconfig-config

echo " hold" | dpkg --set-selections

This command may have the unintended side effect of preventing upgrades to packages that depend on updated versions of the pinned package. apt-get dist-upgrade will override this, but will warn you first. If you want to use this command with sudo, you need to use echo " hold" | sudo dpkg --set-selections not sudo echo " hold" | dpkg --set-selections.

echo " install" | dpkg --set-selections

Removal commands

This command completely removes a package and the associated configuration files. Configuration files residing in ~ are not usually affected by this command.

• + operator
  • If you want to remove package1 and install package2 in one step:

  dpkg -l | grep '^rc' | awk '' | xargs dpkg --purge

  Search commands

  This command determines which installed package owns . It shows files from installed packages that match , with the name of the package they came from. Consider this to be a «reverse lookup» utility.

  In order to use this command, the package dlocate must be installed on your system.

  dpkg -L package | grep /usr/bin

  

  For more information on apt-get, apt-cache and dpkg consult their manual pages by using the man command. These manuals will provide a wider scope of information in addition to all of the options that you can use with each program.

  Example:

  Typical usage example

  I want to feel the wind in my hair, I want the adrenaline of speed. So let’s install a racing game. But what racing games are available?

  apt-cache search racing game

  It gives me a lot of answers. I see a game named «torcs». Let’s get some more information on this game.

  Hmmm. it seems interesting. But is this game not already installed on my computer? And what is the available version? Which repository is it from (Universe or Main)?

  Ok, so now, let’s install it!

  What is the command I must type in the console to launch this game? In this example, it’s straightforward («torcs»), but that’s not always the case. One way of finding the name of the binary is to look at what files the package has installed in «/usr/bin». For games, the binary will be in «/usr/games». For administrative programs, it’s in «/usr/sbin».

  dpkg -L torcs | grep /usr/games/

  The first part of the command display all files installed by the package «torcs» (try it). With the second part, we ask to only display lines containing «/usr/games/».

  Hmmm, that game is cool. Maybe there are some extra tracks?

  But I’m running out of space. I will delete the apt cache!

  Oh no, my mother asked me to remove all games from this computer. But I want to keep the configuration files so I can simply re-install it later.

  If I want to also remove config files :

  Setting up apt-get to use a http-proxy

  These are three methods of using apt-get with a http-proxy.

  Temporary proxy session

  This is a temporary method that you can manually use each time you want to use apt-get through a http-proxy. This method is useful if you only want to temporarily use a http-proxy.

  Enter this line in the terminal prior to using apt-get (substitute your details for yourproxyaddress and proxyport).

  export http_proxy=http://yourproxyaddress:proxyport

  If you normally use sudo to run apt-get you will need to login as root first for this to work unless you also add some explicit environment settings to /etc/sudoers, e.g.

  Defaults env_keep = "http_proxy https_proxy ftp_proxy"

  APT configuration file method

  This method uses the apt.conf file which is found in your /etc/apt/ directory. This method is useful if you only want apt-get (and not other applications) to use a http-proxy permanently.

  gksudo gedit /etc/apt/apt.conf

  Add this line to your /etc/apt/apt.conf file (substitute your details for yourproxyaddress and proxyport).

  Acquire::http::Proxy "http://yourproxyaddress:proxyport";

  BASH rc method

  This method adds a two lines to your .bashrc file in your $HOME directory. This method is useful if you would like apt-get and other applications for instance wget, to use a http-proxy.

  Add these lines to the bottom of your ~/.bashrc file (substitute your details for yourproxyaddress and proxyport)

  http_proxy=http://yourproxyaddress:proxyport export http_proxy

  Save the file. Close your terminal window and then open another terminal window or source the ~/.bashrc file:

  Test your proxy with sudo apt-get update and whatever networking tool you desire. You can use firestarter or conky to see active connections.

  If you make a mistake and go back to edit the file again, you can close the terminal and reopen it or you can source ~/.bashrc as shown above.

  How to login a proxy user

  If you need to login to the Proxy server this can be achieved in most cases by using the following layout in specifying the proxy address in http-proxy. (substitute your details for username, password, yourproxyaddress and proxyport)

  http_proxy=http://username:password@yourproxyaddress:proxyport

  Useful additional packages

  Additional links

  Troubleshooting

  Источник