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CSharp · Console

/Program.cs

using System;
using System.Threading;
using System.Threading.Tasks;
					
public class Program
{
	public static void Main()
	{
		Task.Factory.StartNew(Handle);
	}
	
	public static void Handle(){
		Console.WriteLine(Thread.CurrentThread.ManagedThreadId);
		var tcs = new TaskCompletionSource<bool>();
		Task.Run(() => {
			Console.WriteLine(Thread.CurrentThread.ManagedThreadId);
			Thread.Sleep(1000);
			tcs.SetResult(true);
		});
		tcs.Task.Wait();
	}
}