How to watch a bad task and not fall into the cancellation token trap!

Timeout.cs

using System;
using System.Reactive.Linq;
using System.Reactive.Threading.Tasks;
using System.Threading;
using System.Threading.Tasks;

namespace AsyncEvil
{
    class Program
    {
        static void Main(string[] args)
        {
            var evt = new AutoResetEvent(false);

            var task = Task.Run(() =>
            {
                evt.WaitOne();
            });

            task.ToObservable()
                .Timeout(TimeSpan.FromSeconds(5))
                .Subscribe(_ => { }, ex => Console.WriteLine(ex.Message));

            Console.WriteLine("Waiting...");
            Console.ReadKey(true);
        }
    }
}