0xFFFFFFFFFFFFFFFF Traceback with Skype4Py

Question

When using Skype4Py and running my code, I come across this traceback:

Exception in thread Skype4Py API thread:
Traceback (most recent call last):
  File "C:\Python27\lib\threading.py", line 530, in __bootstrap_inner
    self.run()
  File "build\bdist.win-amd64\egg\Skype4Py\api\windows.py", line 92, in run
    if not self.create_window():
  File "build\bdist.win-amd64\egg\Skype4Py\api\windows.py", line 242, in create_
window
    wclass = windll.user32.RegisterClassA(byref(self.window_class))
WindowsError: exception: access violation reading 0xFFFFFFFFFFFFFFFF

It could be any code, with a different function and still the traceback appears.

The traceback still appears when Command Prompt is in administration as well as on an IDE like Eclipse.

Answer 1

After research into this error I noticed that Skype4Py is based on x32 version of Python, which means in order to resolve this issue you will need to stop using x64 versions of Python when using this module.

Answer 2

Modern operating systems detect when a program tries to read non-existent memory (including the very beginning and very end of the otherwise-valid memory range) and throws a memory-access exception. This is designed to detect use of uninitialized pointers. Whatever binary your Skype library is based on must be broken. It's a shame that modern programs still need this kind of hand-holding!

I'm actually a little surprised that you saw a Python backtrace instead of a C backtrace, though. Either the Python library is being really clever here, or I'm wrong.