code: function _cmdSend(idOrArray, msgStr) {
      if (!Array.isArray(idOrArray)) {
          idOrArray = [idOrArray];
      }
      idOrArray.forEach(function (id) {
          var client = _clients[id];
          if (!client) {
              console.error("nodeSocketTransport: Couldn't find client ID: " + id);
          } else {
              client.socket.send(msgStr);
          }
      });
  }
docs: Sends a transport-layer message over the socket.
  @param {number|Array.<number>} idOrArray A client ID or array of client IDs to send the message to.
  @param {string} msgStr The message to send as a JSON string.