aircrack-ng を使おうとインストールすると下記のようになってしまいました。どう対応すればよいでしょうか、、
$ brew install aircrack-ng
Updating Homebrew...
Warning: aircrack-ng 1.4 is already installed, it's just not linked
You can use brew link aircrack-ng
to link this version.
$ brew link aircrack-ng
Linking /usr/local/Cellar/aircrack-ng/1.4...
Error: Could not symlink sbin/airbase-ng
/usr/local/sbin is not writable.
$ sudo ln -s /System/Library/PrivateFrameworks/Apple80211.framework/Versions/Current/Resources/airport /usr/bin/airport
ln: /usr/bin/airport: Operation not permitted