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    <p>Okay I'm trying out a possible solution to this problem using EventWaitHandle. Looking for comments / feedback. Can this work reliably?</p> <pre><code>// Implementation of a manual event class with a DelayedSet method // DelayedSet will set the event after a delay period // TODO: Improve exception handling public sealed class DelayedManualEvent : EventWaitHandle { private SysTimer timer; // using SysTimer = System.Timers.Timer; public DelayedManualEvent() : base(true, EventResetMode.ManualReset) { timer = new SysTimer(); timer.AutoReset = false; timer.Elapsed +=new ElapsedEventHandler(OnTimeout); } public bool DelayedSet(TimeSpan delay) { bool result = false; try { double timeout = delay.TotalMilliseconds; if (timeout &gt; 0 &amp;&amp; timer != null &amp;&amp; Reset()) { timer.Interval = timeout; timer.Start(); result = true; Trace.TraceInformation("DelayedManualEvent.DelayedSet Event will be signaled in {0}ms", delay); } } catch (Exception e) { Trace.TraceError("DelayedManualEvent.DelayedSet Exception {0}\n{1}", e.Message, e.StackTrace); } return result; } private void OnTimeout(object source, ElapsedEventArgs e) { if (timer != null) { timer.Stop(); Trace.TraceInformation("DelayedManualEvent.OnTimeout Event signaled at time {0}", e.SignalTime); } try { if (!Set()) { Trace.TraceError("DelayedManualEvent.OnTimeout Event set failed"); } } catch (Exception ex) { Trace.TraceError("DelayedManualEvent.OnTimeout Exception in signaling event\n{0}]\n{1}", ex.Message, ex.StackTrace); } } protected override void Dispose(bool disposing) { if (timer != null) { timer.Dispose(); } base.Dispose(disposing); } } </code></pre> <p>The way I'm planning to use this:</p> <pre><code>// Pseudocode static DelayedManualEvent delayedEvent = new DelayedManualEvent(); static TimeSpan t1, t2, maxTimeout; public static void DoThis() { if(!delayedEvent.WaitOne(maxTimeout)) return; DoStuff(); delayedEvent.DelayedSet(t1); } public static void DoThat() { if(!delayedEvent.WaitOne(maxTimeout)) return; DoOtherStuff(); delayedEvent.DelayedSet(t2); } </code></pre>
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    1. POHow to implement synchronization with timers in C#
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    1. USamo
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    1. COThe `DelayedSet` method is not thread-safe. Also, your main code now has a different behavior than your original question. Why are the `return` statements in `DoThis` and `DoThat`?
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      1. USBrian Gideon
    2. COIf you're proposing an update to your question, it's customary to edit your question to include it instead of adding it as an answer. To answer your feedback request, though, no, this won't work, in large part due to your using the same instance of DelayedManualEvent in both cases. Additionally, your implementation allows any number of threads through at a time, acting as a floodgate: Either all threads wait or all threads enter both methods at once. See Brian Gideon's answer for what you should be doing instead.
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      1. USChris Hannon
    3. CO@ChrisHannon Apologies, my first question here so I wasn't aware of custom. Will remember this for next time. About the feedback, I think I still haven't been able to articulate my question correctly - the scenario is simpler. I'll edit my question to clarify.
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