function sh_windowpopup(file, name, w, h) {
    var xPos, yPos;
    xPos = (screen.width / 2) - (w / 2);
    yPos = (screen.height / 2) - (h / 2);
    var winProp = ["width=", w, ",height=", h, ",left=", xPos, ",top=", yPos, ",resizable=1,scrollbars=1"];
    win = window.open(file, name, winProp.join(''));
    win.focus();
}