[python-win32] multiprocessing pickle problem in win32

[Rob Brown-Bayliss]

On Wed, Nov 4, 2009 at 5:34 AM, Aahz <aahz at pythoncraft.com> wrote:
> On Tue, Nov 03, 2009, Rob Brown-Bayliss wrote:
>>
>> When I run the following code in linux all goes well.  But when I try
>> in win32 I get a pickle error saying it cant pickle None Type when I
>> start the process.
>
> You need to provide a full traceback.

Here it is.

>>> C:\Python26\lib\site-packages\MySQLdb\__init__.py:34: DeprecationWarning: the sets module is deprecated
  from sets import ImmutableSet
[<Connection(Connection-1, initial)>, <Connection(Connection-2,
initial)>, <Connection(Connection-3, initial)>]
Traceback (most recent call last):
  File "C:\Python26\Lib\SITE-P~1\PYTHON~1\pywin\framework\scriptutils.py",
line 312, in RunScript
    exec codeObject in __main__.__dict__
  File "C:\Quanto2\database_multi.py", line 120, in <module>
    c.start()
  File "C:\Python26\lib\multiprocessing\process.py", line 104, in start
    self._popen = Popen(self)
  File "C:\Python26\lib\multiprocessing\forking.py", line 239, in __init__
    dump(process_obj, to_child, HIGHEST_PROTOCOL)
  File "C:\Python26\lib\multiprocessing\forking.py", line 162, in dump
    ForkingPickler(file, protocol).dump(obj)
  File "C:\Python26\lib\pickle.py", line 224, in dump
    self.save(obj)
  File "C:\Python26\lib\pickle.py", line 331, in save
    self.save_reduce(obj=obj, *rv)
  File "C:\Python26\lib\pickle.py", line 419, in save_reduce
    save(state)
  File "C:\Python26\lib\pickle.py", line 286, in save
    f(self, obj) # Call unbound method with explicit self
  File "C:\Python26\lib\pickle.py", line 649, in save_dict
    self._batch_setitems(obj.iteritems())
  File "C:\Python26\lib\pickle.py", line 681, in _batch_setitems
    save(v)
  File "C:\Python26\lib\pickle.py", line 331, in save
    self.save_reduce(obj=obj, *rv)
  File "C:\Python26\lib\pickle.py", line 419, in save_reduce
    save(state)
  File "C:\Python26\lib\pickle.py", line 286, in save
    f(self, obj) # Call unbound method with explicit self
  File "C:\Python26\lib\pickle.py", line 649, in save_dict
    self._batch_setitems(obj.iteritems())
  File "C:\Python26\lib\pickle.py", line 681, in _batch_setitems
    save(v)
  File "C:\Python26\lib\pickle.py", line 286, in save
    f(self, obj) # Call unbound method with explicit self
  File "C:\Python26\lib\pickle.py", line 649, in save_dict
    self._batch_setitems(obj.iteritems())
  File "C:\Python26\lib\pickle.py", line 680, in _batch_setitems
    save(k)
  File "C:\Python26\lib\pickle.py", line 286, in save
    f(self, obj) # Call unbound method with explicit self
  File "C:\Python26\lib\pickle.py", line 748, in save_global
    (obj, module, name))
PicklingError: Can't pickle <type 'NoneType'>: it's not found as
__builtin__.NoneType


--

Rob