sS hInitSecondaryWebSocket(O... _) {

  optPar S wsVar = "ws2";

  optPar S url;

  if (empty(url)) fail("Need URL for secondary websocket"); 

  optPar S onOpen;

  optPar S onMessage;

  optPar S readyMsg = "WebSocket 2 ready!";

  ret hreconnectingWebSockets()

    + hscript([[

      var ws2Ready = false;

      var ws2InitialMsgs = [];

      var ws2Verbose = false;

      var ]] + wsVar + [[ = new ReconnectingWebSocket(]] + jsQuote(url) + [[);

      ]] + wsVar + [[.onopen = function(event) {

        ws2Ready = true;

        console.log(]] + jsQuote(readyMsg) + [[);

        ws2InitialMsgs.forEach(function(msg) {

          if (ws2Verbose) console.log("Sending initial msg to websocket 2: " + msg);

          ws2.send(msg);

        });

        ]] + jsDropTrailingComments(onOpen) + [[ };

      ]] + wsVar + [[.onmessage = function(event) {

        ]] + unnull(onMessage) + [[

      };

      // add an initial message to send when websocket opens

      // also send it now if ws is open already

      function ws2InitialMsg(msg) {

        ws2InitialMsgs.push(msg);

        if (ws2Ready) {

          if (ws2Verbose) console.log("Sending initial msg to websocket 2: " + msg);

          ws2.send(msg);

        }

      }

    ]]);

}