Linux Software Package
From KevinWiki
Check Package
$ dpkg -l | grep <package name>
$ apt-cache policy <package name>
$ apt-cache search <package name in regular expression>
Troubleshooting
After run apt-get update
if there is a GPG error like
W: GPG error: http://ppa.launchpad.net lucid Release: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 608BF7B93528AE20
Take the last 8 characters from the keyid
e.g.) from the keyid 608BF7B93528AE20 take 3528AE20
Run the following commands
gpg --keyserver keyserver.ubuntu.com --recv 3528AE20 gpg --export --armor 3528AE20 | sudo apt-key add -
OR Use the full keyid and put the 0x before it then run the following commands
wget -q "http://keyserver.ubuntu.com:11371/pks/lookup?op=get&search=0x608BF7B93528AE20" -O- | sudo apt-key add -
If it does not work, remove the port number and try again.
wget -q "http://keyserver.ubuntu.com/pks/lookup?op=get&search=0x608BF7B93528AE20" -O- | sudo apt-key add -
To see all the keys,
sudo apt-key list