using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Diagnostics;

namespace ConsoleApplication1
{
    class Program
    {
        static void Main(string[] args)
        {
            Process[] processes = Process.GetProcessesByName("cmd");
            foreach (Process p in processes)
            {
                var window = p.MainWindowHandle;
                // Do something
            }
        }
    }
}