var el = document.getElementById('my-input');
FileAPI.event.on(el, 'change', function (evt/**Event*/){
  var files = FileAPI.getFiles(evt);
  var xhr = FileAPI.upload({
    url: 'http://rubaxa.org/FileAPI/server/ctrl.php',
    files: { file: files[0] },
    complete: function (err, xhr){
      if( !err ){
        var result = xhr.responseText;
        // ...
      }
    }
  });
});