function addLoadEvent(func) {
	  var oldonload = window.onload;
	  if (typeof window.onload != 'function') {
	    window.onload = func;
	  } else {
	    window.onload = function() {
	      if (oldonload) {
	        oldonload();
	      }
	      func();
	    }
	  }
	}
	
	function addPrintFooter() {
	    var p = document.createElement('p')
	    p.className = 'print-footer';
	    p.innerHTML = window.location.href;
	    document.body.appendChild(p);
	}
	
	// you can use your own event handler here to add the onload
	addLoadEvent(addPrintFooter);