id,summary,reporter,owner,description,type,status,priority,milestone,component,version,resolution,keywords,cc,os,architecture,failure,difficulty,testcase,blockedby,blocking,related
2924,createDirectory: permission denied,simonmar,,"The following program results in an odd ""permission denied"" error from `createDirectory` on Windows.  It is derived from the `createDirectoryIfMIssing001` test, but doesn't involve calling `createDirectoryIfMissing`, only `createDirectory`.

There are two threads, each of which is repeatedly creating a directory and using `removeDirectoryRecursive` to remove it. 

Test program:

{{{
import System.IO
import System.Directory
import Control.Monad
import Control.Concurrent
import Control.Exception
import System.IO.Error

testdir = ""foo""

main = do
  cleanup
  m <- newEmptyMVar
  forkIO $ do replicateM_ 1000 (do create; cleanup); putMVar m ()
  forkIO $ do replicateM_ 1000 (do create; cleanup); putMVar m ()
  replicateM_ 2 $ takeMVar m
  cleanup

create =
  tryJust (guard . isAlreadyExistsError) $ createDirectory testdir

cleanup =
  tryJust (guard . isDoesNotExistError) $ removeDirectoryRecursive testdir
}}}

The result is usually:

{{{
test.exe: CreateDirectory: permission denied (Access is denied.)
}}}

It's not clear (to me at least) why we get this error.  Running the program under !ProcMon shows that there is a `CreateFile` call that returns `DELETE PENDING`, but as far as I can tell this doesn't give rise to an `ERROR_DELETE_PENDING` return from `CreateDirectory`, because that would give a different error message.  Perhaps somewhere in the bowels of the Win32 API a `DELETE_PENDING` is being turned into a permission denied, or something.

This deserves investigation, because I think it might be related to other spurious ""permission denied"" errors we occasionally see on Windows.",bug,closed,high,6.12.3,libraries/directory,6.10.1,invalid,,,Windows,x86,None/Unknown,Unknown,,,,