threads and exception in wxPython

[Thomas Heller]

Peter Hansen <peter at engcorp.com> writes:

> Peter Hansen wrote:
>> So the exception managed to get to the new thread, even though
>> I called SetAsyncExc *before* the thread was even created.
>> Now _that's_ what I call "asynchronous". ;-)
>
> Actually, it's what you call pilot error.  I was retrieving
> threading._get_ident() in the thread initializer *before*
> the thread was even started... stupid pilot.
>
> Here's the final working version:
>
>  >>> class T(threading.Thread):
> ...   def __init__(self):
> ...    threading.Thread.__init__(self)
> ...    self.stopped = False
> ...    self.start()
> ...   def run(self):
> ...    self.id = threading._get_ident()
> ...    try:
> ...      while not self.stopped:
> ...         time.sleep(0.1)
> ...    except:
> ...      print 'thread terminated!'
> ...
>  >>> t = T()
>  >>> t
> <T(Thread-7, started)>
>  >>> asyncexc = ctypes.pythonapi.PyThreadState_SetAsyncExc
>  >>> exc = ctypes.py_object(ValueError)
             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
>  >>> asyncexc(t.id, exc)

I'm not sure this is the way to do it (but py_object is completely
undocumented, so far, and I don't rememeber the details myself).  But,
it is fine to pass the id() of a python object, which is an integer
specifying it's address, when the function expects a PyObject*:

asyncexc(t.id, id(ValueError(42)))

> 1
>  >>> thread terminated!
>
>  >>> t
> <T(Thread-7, stopped)>
>
>
> -Peter

Thomas