how to receive stdin in node

node-tty.js

var onend = function (val) {
    console.log('hi');
    if (val) {
        console.log('received:');
        console.log(val);
    }
    process.exit(0);
};

if (process.stdin.isTTY) {
    onend();
}
else {
    process.stdin.setEncoding('utf8');
    var lines = [];
    process.stdin.on(
        'data',
        function(chunk) {
            lines.push(chunk);
        }
    );
    process.stdin.on(
        'end',
        function() {
            onend(Buffer.concat(lines).toString('utf8'));
        }
    );
}