The IHTMLPerformanceTiming::responseStart property must return the time immediately after the user agent receives the first byte of the response from the server, from relevant application caches, or from local resources.
HRESULT value = object.get_responseStart(ULONGLONG* p);
- Navigation Timing, Section 4.2
The value reported by the IHTMLPerformanceTiming::responseStart property represents the number of milliseconds between the recorded time and midnight January 1, 1970 (UTC).
Windows Internet Explorer 9. This property is supported only for documents displayed in IE9 Standards mode. For more information, see Defining Document Compatibility.
Build date: 11/12/2012