Conoscere la posizione della scrollbar in javascript

function f_scrollLeft() {
        return f_filterResults (
                window.pageXOffset ? window.pageXOffset : 0,
                document.documentElement ? document.documentElement.scrollLeft : 0,
                document.body ? document.body.scrollLeft : 0
        );
}
function f_scrollTop() {
        return f_filterResults (
                window.pageYOffset ? window.pageYOffset : 0,
                document.documentElement ? document.documentElement.scrollTop : 0,
                document.body ? document.body.scrollTop : 0
        );
}
function f_filterResults(n_win, n_docel, n_body) {
        var n_result = n_win ? n_win : 0;
        if (n_docel && (!n_result || (n_result > n_docel)))
                n_result = n_docel;
        return n_body && (!n_result || (n_result > n_body)) ? n_body : n_result;
}