One line command to add host in /etc/hosts at mac os

If i simply echo and output to /etc/hosts, i will get permission denied

sudo echo 127.0.0.1 myhelloword.localhost >> /etc/hosts
-bash: /etc/hosts: Permission denied

That's because echo is being run as root, but shell is the one who actually performing the redirection. The solution will be spawn a new shell to make this work:

sudo -- sh -c "echo 127.0.0.1 myhelloword.localhost >> /etc/hosts"