First create symlink
sudo ln -s /System/Library/PrivateFrameworks/Apple80211.framework/Versions/Current/Resources/airport /usr/local/bin/airport
Once the Symlink is in place you can scan for Wi-Fi
airport -s
Referenced From: http://osxdaily.com/2012/02/28/find-scan-wireless-networks-from-the-command-line-in-mac-os-x/
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