If every you find your self needed to connect to a wireless network with command line only, this is how you do it (all commands are done with root permissions).

First identify your wifi adapter:

ifconfig

you should get a read out of network adapters. Wireless is generally wlan0, but sometimes might be eth1. You can tell it is wireless with a top line readout that looks like this:

wland0 IEEE 802.11bgn ESSID:”"

now you have identified your wifi adapter lets scan for wireless devices.

iwlist wlan0 scan

Now if there are any wireless devices in range you will have a print out of them. What you are looking for is to see if access is encrypted and the ESSID which identifies the network apart from the others. The read outs will look like this:

Encryption Key”on
ESSID: “MyNetwork”

now that you are armed with the information you need:

iwconfig wlan0 essid MyNetwork
ifconfig wlan0 up
dhclient wlan0

Alternatevely, you can use dhcpd inplace of dhclient. this is for an open network. I have yet to figure out how to access an encrypted network with the command line.