Linux Ask!

Linux Ask! is a Q & A web site specific for Linux related questions. Questions are collected, answered and audited by experienced Linux users.

How to completely uninstall a package in Ubuntu/Debian?

Answer:

To completely uninstall a package in Ubuntu/Debian, you can use the command below:

# sudo apt-get --purge remove PACKAGE

That's it.

Displays information about package in Ubuntu

Answer:

To display the package information about a package, in Ubuntu, type

# apt-cache show curl
Package: curl
Priority: optional
Section: web
Installed-Size: 308
Maintainer: Ubuntu Core Developers 
Original-Maintainer: Domenico Andreoli 
Architecture: amd64
Version: 7.19.5-1ubuntu2
Replaces: curl-ssl
Provides: curl-ssl
Depends: libc6 (>= 2.7), libcurl3 (>= 7.16.2-1), zlib1g (>= 1:1.1.4)
Filename: pool/main/c/curl/curl_7.19.5-1ubuntu2_amd64.deb
Size: 197480
MD5sum: 128a19e9ac7be831b7dd1b67b03dd495
SHA1: dcdec0bb1615465b93ee25368007e8613e3d9fe5
SHA256: 57dabdb5bde28c1c5e5ac96e56e95147f97817048c3be0f050f163af9c40473e
Description: Get a file from an HTTP, HTTPS or FTP server
 curl is a client to get files from servers using any of the supported
 protocols. The command is designed to work without user interaction
 or any kind of interactivity.
 .
 curl offers a busload of useful tricks like proxy support, user
 authentication, ftp upload, HTTP post, file transfer resume and more.
Homepage: http://curl.haxx.se
Bugs: https://bugs.launchpad.net/ubuntu/+filebug
Origin: Ubuntu
Task: uec

Lists the package to which a particular file belongs in Ubuntu

Answer:

Sometimes, you want to know which package contains a file, e.g. "php5.conf", you can try

# dpkg -S php5.conf
libapache2-mod-php5: /etc/apache2/mods-available/php5.conf

List all installed package in Ubuntu

Answer:

To list all the installed packages in Ubuntu, so you try the "dpkg -l" command:

E.g.

# dpkg -l

Add a User in Linux

Answer:

Add a User in Linux, just use the useradd command:

# sudo useradd -d /home/john -m john

The above command will create the user john and create a home directory which is at /home/john