/*
	 * If calibration cycle occurred after we get curCounter
	 */

	if (curCounter.QuadPart <= perfCounterLastCall) {
	    /*
	     * Calibrated file-time is saved from posix in 100-ns ticks
	     * Calibrated file-time is saved from Posix in 100-ns ticks
	     */

	    return fileTimeLastCall / 10;
	}

	/*
	 * If it appears to be more than 1.1 seconds since the last trip
	 * through the calibration loop, the performance counter may have
	 * jumped forward. (See MSDN Knowledge Base article Q274323 for a
	 * description of the hardware problem that makes this test
	 * necessary.) If the counter jumps, we don't want to use it directly.
	 * Instead, we must return system time. Eventually, the calibration
	 * loop should recover.
	 */

	if (curCounter.QuadPart - perfCounterLastCall <
		11 * curCounterFreq * timeInfo.calibrationInterv / 10) {
	    /*
	     * Calibrated file-time is saved from posix in 100-ns ticks.
	     * Calibrated file-time is saved from Posix in 100-ns ticks.
	     */

	    return NativeCalc100NsTicks(fileTimeLastCall,
		    perfCounterLastCall, curCounterFreq,
		    curCounter.QuadPart) / 10;
	}
    }

    GetSystemTimeAsFileTime(&curFileTime);
    QueryPerformanceCounter(&timeInfo.perfCounterLastCall);
    QueryPerformanceFrequency(&timeInfo.curCounterFreq);
    timeInfo.fileTimeLastCall.LowPart = curFileTime.dwLowDateTime;
    timeInfo.fileTimeLastCall.HighPart = curFileTime.dwHighDateTime;

    /*
     * Calibrated file-time will be saved from posix in 100-ns ticks.
     * Calibrated file-time will be saved from Posix in 100-ns ticks.
     */

    timeInfo.fileTimeLastCall.QuadPart -= timeInfo.posixEpoch.QuadPart;

    ResetCounterSamples(timeInfo.fileTimeLastCall.QuadPart,
	    timeInfo.perfCounterLastCall.QuadPart,
	    timeInfo.curCounterFreq.QuadPart);

    long long vt1;		/* Tcl time one second from now. */
    long long tdiff;		/* Difference between system clock and Tcl
				 * time. */
    long long driftFreq;	/* Frequency needed to drift virtual time into
				 * step over 1 second. */

    /*
     * Sample performance counter and system time (from posix epoch).
     * Sample performance counter and system time (from Posix epoch).
     */

    GetSystemTimeAsFileTime(&curSysTime);
    curFileTime.LowPart = curSysTime.dwLowDateTime;
    curFileTime.HighPart = curSysTime.dwHighDateTime;
    curFileTime.QuadPart -= timeInfo.posixEpoch.QuadPart;

	return;
    }
    QueryPerformanceCounter(&curPerfCounter);

    lastFileTime.QuadPart = curFileTime.QuadPart;

    /*
     * We devide by timeInfo.curCounterFreq.QuadPart in several places. That
     * We divide by timeInfo.curCounterFreq.QuadPart in several places. That
     * value should always be positive on a correctly functioning system. But
     * it is good to be defensive about such matters. So if something goes
     * wrong and the value does goes to zero, we clear the
     * timeInfo.perfCounterAvailable in order to cause the calibration thread
     * to shut itself down, then return without additional processing.
     */