I'm trying to use fish shell as my default shell on OSX. I have installed fish shell using brew and when I wanted to add it to /etc/shells I got this error:

tee: /etc/shells: No such file or directory

Here's the command line I used:

echo "usr/local/bin/fish" | sudo tee -a /etc/shells

Source: https://hackercodex.com/guide/install-fish-shell-mac-ubuntu/

Is there something wrong with my $PATH?