linkIcons = function() {
  var links = document.getElementsByTagName("a");
  for (i=0; i < links.length; i++) {
    var currentLink = links[i];
    var images = currentLink.getElementsByTagName("img");
    if (images.length == 0 && currentLink.href.indexOf('.pdf') != -1) {
      var newImg=document.createElement('img');
      newImg.setAttribute('src','../../images/pdficon.gif');
      currentLink.appendChild(newImg);
    }
    if (images.length == 0 && currentLink.href.indexOf('.doc') != -1) {
      var newImg=document.createElement('img');
      newImg.setAttribute('src','doc.png');
      currentLink.appendChild(newImg);
    }
    if (images.length == 0 && currentLink.target == "_blank") {
      var newImg=document.createElement('img');
      newImg.setAttribute('src','new_window.png');
      currentLink.appendChild(newImg);
    }
  }
}

function addLoadEvent(func) {
  var oldonload = window.onload;
  if (typeof window.onload != 'function') {
    window.onload = func;
  } else {
    window.onload = function() {
      if (oldonload) {
        oldonload();
      }
      func();
    }
  }
}

addLoadEvent(linkIcons);