I tried making a symbolic link to the airport command in MAC OS X El Capitan, using the command:
sudo ln -s /System/Library/PrivateFrameworks/Apple80211.framework/Versions/Current/Resources/airport /usr/sbin/airport
It returned the following error:
ln: /usr/sbin/airport: Operation not permitted
Is this due to the El Capitan's "rootless" feature? The sym link worked fine in MAC OS X Yosemite.
The target directory should be /usr/local/bin/airport
See the article on System Integrity Protection for more information as to why the directories have changed.
sudo ln -s /System/Library/PrivateFrameworks/Apple80211.framework/Versions/Current/Resources/airport /usr/local/bin/airport