- When run with patch 20 as non-admin on Windows 7, I get the same test_tarfile errors that Brian gets. I do not get these errors with an unpatched py3k build.

- When run with patch 20 as an admin on Windows 7, I do not get the errors in test_tarfile. However, I do get errors in test_posixpath that I do not get on an unpatched py3k build:
======================================================================
FAIL: test_realpath_basic (test.test_posixpath.PosixPathTest)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "C:\opt\cygwin\home\eric\python\py3k\lib\test\test_posixpath.py", line 49
9, in test_realpath_basic
    self.assertEqual(realpath(ABSTFN), ABSTFN+"1")
AssertionError: 'C:\\opt\\cygwin\\home\\eric\\python\\py3k/C:\\opt\\cygwin\\home
\\eric\\python\\py3k/C:\\opt\\cygwin\\home\\eric\\python\\py3k/@test_3404_tmp1'
!= 'C:\\opt\\cygwin\\home\\eric\\python\\py3k/@test_3404_tmp1'

======================================================================
FAIL: test_realpath_resolve_before_normalizing (test.test_posixpath.PosixPathTes
t)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "C:\opt\cygwin\home\eric\python\py3k\lib\test\test_posixpath.py", line 56
0, in test_realpath_resolve_before_normalizing
    self.assertEqual(realpath(ABSTFN + "/link-y/.."), ABSTFN + "/k")
AssertionError: 'C:\\opt\\cygwin\\home\\eric\\python\\py3k/C:\\opt\\cygwin\\home
\\eric\\python\\py3k/@test_3404_tmp/C:\\opt\\cygwin\\home\\eric\\python\\py3k/@t
est_3404_tmp/k' != 'C:\\opt\\cygwin\\home\\eric\\python\\py3k/@test_3404_tmp/k'

======================================================================
FAIL: test_realpath_resolve_first (test.test_posixpath.PosixPathTest)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "C:\opt\cygwin\home\eric\python\py3k\lib\test\test_posixpath.py", line 58
3, in test_realpath_resolve_first
    self.assertEqual(realpath(base + "link"), ABSTFN)
AssertionError: 'C:\\opt\\cygwin\\home\\eric\\python\\py3k/C:\\opt\\cygwin\\home
\\eric\\python\\py3k/@test_3404_tmp' != 'C:\\opt\\cygwin\\home\\eric\\python\\py
3k/@test_3404_tmp'

======================================================================
FAIL: test_realpath_resolve_parents (test.test_posixpath.PosixPathTest)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "C:\opt\cygwin\home\eric\python\py3k\lib\test\test_posixpath.py", line 53
7, in test_realpath_resolve_parents
    self.assertEqual(realpath("a"), ABSTFN + "/y/a")
AssertionError: 'C:\\opt\\cygwin\\home\\eric\\python\\py3k\\@test_3404_tmp\\k/a'
 != 'C:\\opt\\cygwin\\home\\eric\\python\\py3k/@test_3404_tmp/y/a'

======================================================================
FAIL: test_realpath_symlink_loops (test.test_posixpath.PosixPathTest)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "C:\opt\cygwin\home\eric\python\py3k\lib\test\test_posixpath.py", line 50
9, in test_realpath_symlink_loops
    self.assertEqual(realpath(ABSTFN), ABSTFN)
AssertionError: 'C:\\opt\\cygwin\\home\\eric\\python\\py3k/C:\\opt\\cygwin\\home
\\eric\\python\\py3k/C:\\opt\\cygwin\\home\\eric\\python\\py3k/@test_3404_tmp' !
= 'C:\\opt\\cygwin\\home\\eric\\python\\py3k/@test_3404_tmp'

======================================================================
FAIL: test_samefile (test.test_posixpath.PosixPathTest)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "C:\opt\cygwin\home\eric\python\py3k\lib\test\test_posixpath.py", line 34
3, in test_samefile
    False
  File "C:\opt\cygwin\home\eric\python\py3k\lib\test\test_posixpath.py", line 29
, in assertIs
    self.assertTrue(a is b)
AssertionError: False is not True

======================================================================
FAIL: test_samestat (test.test_posixpath.PosixPathTest)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "C:\opt\cygwin\home\eric\python\py3k\lib\test\test_posixpath.py", line 38
4, in test_samestat
    False
  File "C:\opt\cygwin\home\eric\python\py3k\lib\test\test_posixpath.py", line 29
, in assertIs
    self.assertTrue(a is b)
AssertionError: False is not True

----------------------------------------------------------------------
Ran 30 tests in 0.201s

FAILED (failures=7)
test test_posixpath failed -- multiple errors occurred
1 test failed:
    test_posixpath

Even though "cygwin" is in the path, I am running these tests from a cmd.exe (or whatever the built-in shell is called these days) shell. I am not running these tests under cygwin bash.