title: How to implement Barrier class from .NET 4 functionality in .NET 3.5
body: <p>For some reasons I have to stick to .NET 3.5 and I need a functionality of Barrier class from .NET 4. I have a bunch of threads that do some work and I want them to wait for each other until all are done. When all are done I want that they do the job again and again in the similar manner.
  Encouraged by the thread <a href="https://stackoverflow.com/questions/990970/difference-between-barrier-in-c-4-0-and-waithandle-in-c-3-0">Difference between Barrier in C# 4.0 and WaitHandle in C# 3.0?</a> I have decided to implement the Barrier functionality with AutoResetEvent and WaitHandle classes.
  Altough I encounter a problem with my code:</p>
  
  <pre><code>class Program
  {
      const int numOfThreads = 3;
  
      static AutoResetEvent[] barrier = new AutoResetEvent[numOfThreads];
      static Random random = new Random(System.DateTime.Now.Millisecond);
  
      static void barriers2(object barrierObj)
      {
          AutoResetEvent[] barrierLocal = (AutoResetEvent[])barrierObj;
          string name = Thread.CurrentThread.Name;
          for (int i = 0; i &lt; 10; i++)
          {
              int sleepTime = random.Next(2000, 10000);
              System.Console.Out.WriteLine("Thread {0} at the 'barrier' will sleep for {1}.", name, sleepTime);
              Thread.Sleep(sleepTime);
              System.Console.Out.WriteLine("Thread {0} at the 'barrier' with time {1}.", name, sleepTime);
              int currentId = Convert.ToInt32(name);
              //for(int z = 0; z &lt; numOfThreads; z++)
                  barrierLocal[currentId].Set();
              WaitHandle.WaitAll(barrier);
              /*
              for (int k = 0; k &lt; numOfThreads; k++)
              {
                  if (k == currentId)
                  {
                      continue;
                  }
                  System.Console.Out.WriteLine("Thread {0} is about to wait for the singla from thread: {1}", name, k);
                  barrierLocal[k].WaitOne();
                  System.Console.Out.WriteLine("Thread {0} is about to wait for the singla from thread: {1}. done", name, k);
              }
              */
          }
      }
  
      static void Main(string[] args)
      {
          for (int i = 0; i &lt; numOfThreads; i++)
          {
              barrier[i] = new AutoResetEvent(false);
          }
          for (int i = 0; i &lt; numOfThreads; i++)
          {
              Thread t = new Thread(Program.barriers2);
              t.Name = Convert.ToString(i);
              t.Start(barrier);
          }
      }
  }
  </code></pre>
  
  <p>The output I receive is as follows:</p>
  
  <p>Thread 0 at the 'barrier' will sleep for 7564
  Thread 1 at the 'barrier' will sleep for 5123
  Thread 2 at the 'barrier' will sleep for 4237
  Thread 2 at the 'barrier' with time 4237
  Thread 1 at the 'barrier' with time 5123
  Thread 0 at the 'barrier' with time 7564
  Thread 0 at the 'barrier' will sleep for 8641
  Thread 0 at the 'barrier' with time 8641</p>
  
  <p>And that's it. After the last line there is no more output and the app does not terminate. It looks like there is some sort of deadlock. However can not find the issue. Any help welcome.</p>
  
  <p>Thanks!</p>