macOS uses `\r` instead of `\n` for `return`. https://github.com/clue/php-stdio-react/blob/master/src/Readline.php#L47
macOS uses
\rinstead of\nforreturn.https://github.com/clue/php-stdio-react/blob/master/src/Readline.php#L47