In the EEROS library you will find a directory with examples. Open a shell in the build directory of your EEROS library and run examples/controlsystem/xBoxTest. This examples reads and outputs periodically all 8 buttons and 8 axis of a XBox controller. Further, the safety system checks for the button 'X' to be pressed. This causes a level change. As soon as the button is released the safety system changes back to the first level.
If you connect several such controller you have to check in /dev/input/ for the controller of your choice and adapt the program accordingly.