/// <summary>
/// Retrieves the current state of the clock.
/// </summary>
/// <param name="clock">A valid IMFClock instance.</param>
/// <param name="clockState">Receives the clock state</param>
/// <returns>If this function succeeds, it returns the S_OK member. Otherwise, it returns another HResult's member that describe the error.</returns>
public static HResult GetState(this IMFClock clock, out MFClockState clockState)
{
if (clock == null)
{
throw new ArgumentNullException("clock");
}
return(clock.GetState(0, out clockState));
}