port scanning

[Detlef Lechner]

Hi,

[GNOME] System > Administration > Network Tools. DEB program package
gnome-nettool. Synaptic: "GNOME Nettool is a network information tool
which provides user interfaces for some of the most common command line
network tools including: * ifconfig, * ping, * netstat, * tracepath, *
port scanning, * DNS lookup, * finger, * whois."
What is the underlying command-line command for this "* port scanning"?

Regards,
Detlef Lechner