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====== Managing Packages ====== Useful information about managing packages can be found [[http://newbiedoc.sourceforge.net/tutorials/apt-get-intro/info.html.en|in the Source Forge newbie documentation]]. Here are a few commands that might come handy whenever you seek information about [installed] packages on your system: ==== Updating package list from sources ==== One thing you always need to do before working with packages on your system, is **make sure your package list is up-to-date**, this is achieved by using this command: <code> sudo apt-get update </code> This will simply update your package list information, it won't install or modify anything further, so it is safe to run anytime. ==== Search the package descriptions you've downloaded ==== apt-cache only knows about the **package descriptions you've already downloaded**, to search among **ALL** known Debian packages you need to browse to [[http://packages.debian.org/]] to see what's available. Example: getting information about php <code> sudo apt-cache search php5 </code> ==== Get more information about a package ==== To display what a package is designed to do, use: <code> apt-cache show php5-dev </code> ==== List all installed packages ==== To show **what packages are installed** on your system, and know if they need configuration use: <code> sudo dpkg -l </code> You can limit the output using grep: <code> sudo dpkg -l | grep php </code> **NOTE** dpkg -l can be use with the \* or '*' argument to also list uninstalled packages: <code> sudo dpkg -l \* sudo dpkg -l \*php\* </code> This is equivalent to: <code> sudo dpkg -l '*' sudo dpkg -l '*php*' </code> This will let you know what packages are installed (ii), uninstalled (un) or are marked to be purged (pn). ==== Find what package a specific file does come from ==== Here's how to find which package contains/supplies a certain file: <code> sudo dpkg -S postmaster sudo dpkg -S 'doc/*sql' | cut -f1 -d: | sort -u </code> ===== Adding a Repo(sitory) to Your Sources ===== ==== Package Management ==== Debian and Debian based distributions (Linspire, Xandros, Ubuntu, and Mepis to name a few) use a tool called APT (Advanced Packaging Tool) to manage all software on the system. The term "package" refers to an individual file with a .deb extension that contains either all or part of an application. APT checks to ensure that all necessary packages are available prior to installing a program and also prevents the accidental deletion of a package if another program is dependent upon it. All available software is stored in a repository. Most of these are online. Linux Mint Debian Edition comes with some default repositories that are already setup, but these contain only a portion of the freely available software out there waiting for you. ==== /etc/apt/sources.list ==== The// /etc/apt/sources.list/// file contains the details for each available software repository. This file can either be edited manually or it can be modified by using a graphical manager. Examples for both are provided below. All entries in the sources.list file follow a format with 4 distinct regions: package type, web address (URL), distribution, and section(s). One or more sections can be included. <code> deb http://host/debian distribution section1 section2 section3 deb-src http://host/debian distribution section1 section2 section3 deb http://http.us.debian.org/debian stable main contrib non-free deb-src http://http.us.debian.org/debian stable main </code> ==== /etc/apt/sources.list.d ==== In case you do not want to "pollute" your sources.list file with third-parties repos, you can also create a new file in the// etc/apt/sources.list.d// repository. Creating a file with a .list extension and adding the repo's reference there will also add it to your sources list: <code> sudo nano /etc/apt/sources.list.d/new-repo.list ----- deb http://download.myrepo.org/repository/debian wheezy contrib non-free deb-src http://download.myrepo.org/repository/debian wheezy contrib non-free ----- CTRL-x > Y (exit nano and save file) </code> ==== Source Packages ==== No all repos provide source packages, if a repo only provides .deb packages, omit the second line (deb-src) when adding the repo to your sources. Otherwise, apt-get update will stop with an error of type: <code> Failed to fetch http://download.myrepo.org/repository/debian/dists/wheezy/InRelease Unable to find expected entry 'contrib/source/Sources' in Release file (Wrong sources.list entry or malformed file) </code> ==== Signing Keys ==== Most of the "serious" complementary repositories, will require you to install a signing key to allow secured identification of the repositories. This is done through first downloading the key provided by the repo, then issuing a command of type: <code> sudo apt-key add secure_key.asc </code> Or you could combine downloading the key and registering it: <code> wget -q http://download.myrepo.org/repo/secure_key.asc -O- | sudo apt-key add - </code> ==== All-in-one Operation ==== <wrap important> This is mostly for Ubuntu's ppa and doesn't quite often works for LMDE.</wrap> It allows to use the add-apt-repository command that will append the repository to /etc/apt/sources.list and add the repository key to the machine: <code> sudo add-apt-repository deb http://download.myrepo.org/repository/debian wheezy contrib </code> The add-apt-repository is in the python-software-properties package: <code> sudo apt-get install python-software-properties </code> ==== Package / Software Managers ====