[Pancake]

To use "printf", simply do

printf("Hello World!");

Or if you want to print a variable:

float number = 7.241;
printf("The value is: %f", number); // The value is: 7.241

And you need the cRIO connected to your computer via a serial cable to see the output

For the joystick issue, (I haven't actually tested it myself), I think it should work like:

Joystick stick(1); // Joystick plugged into USB port 1
Servo sv1(5); 


if(stick.GetRawButton(2))
{
    // Set the servo
    sv1.set(someAngle);
}

Hope this helps, haven't actually tried this myself