private static void ThreadProc() { #if NET20 localOffset = (int)TimeZone.CurrentTimeZone.GetUtcOffset(DateTime.UtcNow).TotalMinutes; #else localOffset = (int)TimeZoneInfo.Local.GetUtcOffset(DateTime.UtcNow).TotalMinutes; #endif // Only check for offset changes every new minute (plus 1 second safety margin) to save // resources for clearing the TimeZoneInfo cache nextOffsetCheck = DateTime.UtcNow.Ticks / 600000000 * 600000000 + 610000000; do { try { Thread.Sleep(CheckInterval); } catch (ThreadInterruptedException) { // That's fine. } // Check for UTC time changes TimeSpan offset = DateTime.UtcNow - FL.UtcNow; if (Math.Abs(offset.TotalMilliseconds) >= FL.CheckTimeThreshold) { FL.RebaseTime(); string msg = "System time changed by " + offset.TotalMilliseconds.ToString("0.0", CultureInfo.InvariantCulture) + " ms"; FL.Info(msg, "Changes less than " + FL.CheckTimeThreshold + " ms are not reported."); Debug.WriteLine(msg); prevLoggedOffset = 0; } else if (FL.LogTimeThreshold >= 0 && Math.Abs(offset.TotalMilliseconds - prevLoggedOffset) > FL.LogTimeThreshold) { FL.TraceData("System time offset", offset.TotalMilliseconds); prevLoggedOffset = offset.TotalMilliseconds; } // Check for local time zone changes if (DateTime.UtcNow.Ticks >= nextOffsetCheck) { // Clear the cache to get the real current setting #if NET20 int newLocalOffset = (int)TimeZone.CurrentTimeZone.GetUtcOffset(DateTime.UtcNow).TotalMinutes; #else TimeZoneInfo.ClearCachedData(); int newLocalOffset = (int)TimeZoneInfo.Local.GetUtcOffset(DateTime.UtcNow).TotalMinutes; #endif if (newLocalOffset != localOffset) { int hours = localOffset / 60; int mins = Math.Abs(localOffset) % 60; int newHours = newLocalOffset / 60; int newMins = Math.Abs(newLocalOffset) % 60; localOffset = newLocalOffset; string msg = "Local time UTC offset changed from " + hours.ToString("+00;-00;+00") + ":" + mins.ToString("00") + " to " + newHours.ToString("+00;-00;+00") + ":" + newMins.ToString("00"); string details = "\u0001UtcOffset=" + newLocalOffset; FL.Notice(msg, details); Debug.WriteLine(msg); } nextOffsetCheck = DateTime.UtcNow.Ticks / 600000000 * 600000000 + 610000000; } }while (!cancelPending); }