We can simply confirm the handle released to open it with EXCLUSIVE. Attempting renaming was bad.
Disable win32file at ImportError. Thanks to Francois to let me know.
FIXME: Could we report warning or notification if win32file were not found?
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@153172 91177308-0d34-0410-b5e6-96231b3b80d8