Matevž Gačnik's Weblog

If you happen to be on a Windows Vista or Windows Server 2008 box, there is some goodness going your way.

There is a basic managed TxF (Transactional NTFS) wrapper available (unveiled by Jason Olson).

What this thing gives you is this:

try
{
   using (TransactionScope tsFiles = new TransactionScope
      TransactionScopeOption.RequiresNew))
   {
      WriteFile("TxFile1.txt");
      throw new FileNotFoundException();
      WriteFile("TxFile2.txt");
      tsFiles.Complete();
   }
}
catch (Exception ex)
{
   Console.WriteLine(ex.Message);
}

WriteFile method that does, well, file writing, is here:

using (TransactionScope tsFile = new TransactionScope
      (TransactionScopeOption.Required))
{
   Console.WriteLine("Creating transacted file '{0}'.", filename);

   using (StreamWriter tFile = new StreamWriter(TransactedFile.Open(filename, 
          FileMode.Create,
          FileAccess.Write,
          FileShare.None)))
   {
      tFile.Write(String.Format("Random data. My filename is '{0}'.",
          filename));
   }

   tsFile.Complete();
   Console.WriteLine("File '{0}' written.", filename);
}

So we have a nested TransactionScope with a curious type - TransactedFile. Mind you, there is support for TransactedDirectory built in.

What's happening underneath is awesome. The wrapper talks to unmanaged implementation of TxF, which is built in on every Vista / Longhorn Server box.

What you get is transactional file system support with System.Transactions. And it's going to go far beyond that.

I wrote some sample code, go get it. Oh, BTW, remove the exception line to see the real benefit.

Download: Sample code

This sample is provided without any warranty. It's a sample, so don't use it in production environments.