Retrieve available Wifi networks on Ubuntu

Question

I'm starting to learn Ubuntu 9.10. How can I retrieve all available Wifi networks programmatically? Can someone give an example?

Answer 1

check if you have iwconfig

Answer 2

sudo iwlist wlan0 scan

if wlan0 is your wifi-interface

Answer 3

This is definitely a duplicate of "How can I get a list of available wireless networks on Linux?" unless you are asking for a higher-level language than C.