Check if a specific package has been installed or not

% dpkg --get-selections 'squeeze*'

To check the version of the installed package, use dpkg-query:

% dpkg-query -s squeezecenter

How to check the Ubuntu release version?

See /etc/lsb-release file.

LSB stands for Linux Standard Base.

(08/11/2009)

ubuntu boot doesn't start a daemon

I wanted to disable dnsmasq on boot.

Edit /etc/default/dnsmasq.  Change ENABLED=1 to ENABLED=0.

(12/29/2008)