[MERGE] Implement bzrlib.lock with CreateFile rather than LockFileEx on win32 (operational part)

[John Arbash Meinel]

John Arbash Meinel has voted approve.
Status is now: Approved
Comment:
So I can confirm that
1) the locking is properly exclusive on Vista
2) Older clients are exclusive with newer clients (on vista with 
win32file available)
3) The ctypes implementation is exclusive with the win32file 
implementation
4) Read locks exclude writers, but not other readers (between versions, 
etc)
5) write locks exclude readers (not checking writers because we exclude 
them with directory locks)

I have no idea what this does for things like Win98, but at least the 
edge cases I consider important work correctly on Vista.

Good job.


For details, see: 
http://bundlebuggy.aaronbentley.com/project/bzr/request/%3Cd80792120906190310p78d4c7e6t2b2bb64174467bac%40mail.gmail.com%3E
Project: Bazaar