.NET Is there a way to get the parent thread id?

Question

Suppose the main thread is spawning a new thread t1, how can my code that runs on t1 find the thread id of the main thread (using c#)?

Edit:
I don\'t control the

Answer 1

If you are using a Threadpool (thus no control over the creation of Threads here) you could work as follows:

private static void myfunc(string arg)
{
    Console.WriteLine("Thread "
                     + Thread.CurrentThread.ManagedThreadId
                     + " with parent " + Thread.GetData(Thread.GetNamedDataSlot("ParentThreadId")).ToString()
                     + ", with argument: " 
                     + arg
                     );
}
public static int Main(string[] args)
{
    var parentThreadId = System.Threading.Thread.CurrentThread.ManagedThreadId;
    WaitCallback waitCallback = (object pp) =>
    {
        Thread.SetData(Thread.GetNamedDataSlot("ParentThreadId"), parentThreadId);
        myfunc(pp.ToString());
    };

    ThreadPool.QueueUserWorkItem(waitCallback, "my actual thread argument");
    Thread.Sleep(1000);
    return 0;
}

This would produce something like:

 Thread 3 with parent 1, with argument: my actual thread argument

If however there is no way to pass data to the child thread at all, consider renaming the parent thread, or alternatively all the child threads.