How to prevent caching of Ajax request using Dojo

The Portlet Specification 2.0 allows you set cache-control header on response of serveResource() call. So what you can do is inside the serveResource() method set max-age for your response like this
PortletResponse.getCacheControl().setExpirationTime(100000);

Now the question is what if i want to prevent response from being cached if thats the case you can set preventCache flag to true while making dojo request like this

 dojo.xhrGet({
    url: "",
    preventCache: true,
    load: function(data, ioargs){
      dojo.byId("resourceResponse").innerHTML = data;
    },
    error: function(error,ioargs){
      alert(error);
    }
});  

What the preventCache flag would do is that it will append dojo.preventCache query parameter to the url before making request so in my case it will take the <portlet:resourceURL/> and append the dojo.preventCache query parameter and the value of dojo.preventCache parameter will change every time the xhr call is made so server will always return the full response.