/* format URL as file extension */
webreadext(s)
{
        s = strrep(s, "\", "");
        s = strrep(s, "/", "");
        s = strrep(s, "+", "");
        s = strrep(s, "-", "");
        s = strrep(s, "=", "");
        s = strrep(s, "'", "");
        s = strrep(s, '"', "");
        s = strrep(s, ".", "_");

        s = strextract(s, 1, 16);

        return(s);
}