Refreshing the wireless network list?

When I wake up my laptop (Ubuntu 10.04) from suspension, it does not recognize the available wireless networks. The only way to refresh the list is to disable wireless networking, and than enable it.

Any idea how to force a refresh on the list of wireless networks?

The best way to refresh the list is to go to the command line and type:

sudo iwlist wlan0 scan

Assuming your wifi is called wlan0 (it might be wlan0 or something else) see ifconfig for details.

On newer versions of Ubuntu you can leave out the wifi name and it will scan all wireless cards:

sudo iwlist scan

This command will refresh the list by asking the wifi to rescan. You can only do this as root and if you do it as non-root it will simply print the list of known networks without refreshing.