Make turtledemo start as active on Mac even when run with subprocess.
Patch by Ramchandra Apt, Lita Cho, and Ned Daily.

deltree().

are not available.  Patch by Arfrever Frehtes Taifersar Arahesis.

pythonw.exe instead of python.exe

in the _cache dictionary, even if we already got the result. We need to keep a
reference to the overlapped object, otherwise the memory may be reused and
GetQueuedCompletionStatus() may use random bytes and behaves badly.

There is still a hack for ConnectNamedPipe(): the overlapped object is not
register into _cache if the overlapped object completed directly.

Log also an error in debug mode in ProactorIocp._loop() if we get an unexpected
event.

Add a protection in ProactorIocp.close() to avoid blocking, even if it should
not happen. I still don't understand exactly why some the completion of some
overlapped objects are not notified.

2009-02-02 51562 (27c589f09a21) merged Mac support revisions into 3.0.
2009-03-04 52014 (dc3d24824b60) merged slightly improved version into 2.7.
Change 3.4+ to match the later 2.7 patch.  Buttons tested manually.

on closed socket. repr(socket.socket) already works fine.

overlapped object. IocpProactor._poll() now also ignores false alarms:
GetQueuedCompletionStatus() returns the overlapped but it is still pending.

* Tulip issue #196: IocpProactor._poll() clears the reference to the
  overlapped operation when the operation is done. It would be better to clear
  the reference in a new _OverlappedFuture.set_result() method, but it cannot
  be done yet because of a weird bug.
* BaseSelectorEventLoop._write_to_self() now logs errors in debug mode.

Patch by Zachary Turner.

* Fix _WaitHandleFuture.cancel(): return the result of the parent cancel()
  method.
* _OverlappedFuture.cancel() now clears its reference to the overlapped object.
  Make also the _OverlappedFuture.ov attribute private.
* Check if _WaitHandleFuture completed before unregistering it in the callback.
  Add also _WaitHandleFuture._poll() and repr(_WaitHandleFuture).
* _WaitHandleFuture now unregisters its wait handler if WaitForSingleObject()
  raises an exception.
* _OverlappedFuture.set_exception() now cancels the overlapped operation.

by removing global 'demo'. Refactor and remove duplicate code.

Improve stability of the proactor event loop, especially operations on
overlapped objects:

* Tulip issue 195: Don't call UnregisterWait() twice if a _WaitHandleFuture is
  cancelled twice to fix a crash.
* IocpProactor.close(): cancel futures to cancel overlapped operations, instead
  of cancelling directly overlapped operations. Future objects may not call
  ov.cancel() if the future was cancelled or if the overlapped was already
  cancelled. The cancel() method of the future may also catch exceptions. Log
  also errors on cancellation.
* tests: rename "f" to "fut"
* Add a __repr__() method to IocpProactor
* Add a destructor to IocpProactor which closes it
* _OverlappedFuture.cancel() doesn't cancel the overlapped anymore if it is
  done: if it is already cancelled or completed. Log also an error if the
  cancellation failed.
* Add the address of the overlapped object in repr(_OverlappedFuture)
* _OverlappedFuture truncates the source traceback to hide the call to the
  parent constructor (useless in debug).

does crash on Mac OS X which uses libedit instead of readline.

BlockingIOError exceptions. Initial patch written by Xavier de Gaye.

Document also in asyncore documentation that recv() may raise BlockingIOError.

terminal to not write the ANSI sequence "\033[1034h" into stdout. This sequence
is used on some terminal (ex: TERM=xterm-256color") to enable support of 8 bit
characters.

Patch written by Saimadhav Heblikar.

Patch by Martin Matusiak.