//Get the latest version of the JSON describing the available content
$.ajax({
    type: "GET",
    url: "/blog/idx",
    success: function(rslt) {
            blogJSON = rslt.hdr_blog_idx;

            var qryStrContentParam = getUrlParam('content');

            setIdx4(qryStrContentParam);

            console.log("Read JSON, currIdx = " + currIdx);
            console.log("           content = " + blogJSON[currIdx].file);

            history.replaceState({hdr_idx: currIdx},
                                  blogJSON[currIdx].desc,
                                  sURL_blog);
        }
});