code: function () {
  			var self = this;
  			console.log('starting capture...');
  			var req = get_req();
  			req.onreadystatechange = function start_capture_response () {
  				if (req.readyState === 4) {
  					if (req.status == 200) {
  						console.log('started.');
  						jQuery("#start").hide();
  						jQuery("#stop").show();
  					  htracr.ui.pulse_logo();
  					} else {
  						var error = eval("(" + req.responseText + ")");
  						alert("Sorry, I can't start the sniffer; it says \"" +
  						  error.message + "\"."
  						);
  						console.log("start problem: " + error);
  					}
  				}
  			};
  			req.open("POST", "/start", true);
  			req.send("");
  			return false;
  		}
docs: start capturing a session