Every time I try to find out how to do this, I find out how to do it on a linux, and it doesn't transfer. How do I connect to a WiFi network using Mac Terminal Bash?
As of Snow Leopard (Mac OS X v10.6.x) and possibly earlier, you can do:
networksetup -setairportnetwork $INTERFACE $SSID $PASSWORD
$INTERFACEis the "enX" style identifier for your AirPort card (usually
en1, but it's
en0on MacBook Airs and
en2on Mac Pros, and can vary for other reasons as well)
$SSIDis your network name, such as
"Simon's SSID". Enclose it in quotes if it contains spaces.
$PASSWORDis your WEP, WPA-PSK, or WPA2-PSK password.
If you look at the man page or help/usage statement for
networksetup you'll see that it has other AirPort-related subcommand for getting or setting the power state (AirPort card on/off), and for managing the Preferred Networks list and 802.1X profiles (if your network uses 802.1X, such as a WPA Enterprise or WPA2 Enterprise network would).
Here is a little guide on using airport in the Command Line
Apparently you can use
as a command. I would try
$ airport -help
and see if it brings up some options.
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