Ctypes c_void_p overflow

[Joseph L. Casale]

> I generally avoid c_void_p because its lenient from_param method
> (called to convert arguments) doesn't provide much type safety. If a
> bug causes an incorrect argument to be passed, I prefer getting an
> immediate ctypes.ArgumentError rather than a segfault or data
> corruption. For example, when a C API returns a void pointer as a
> handle for an opaque structure or object, I prefer to handle it as a
> pointer to an empty Structure subclass, as follows:
>
>     class _ContosoHandle(ctypes.Structure):
>         pass
>
>     ContosoHandle = ctypes.POINTER(_ContosoHandle)
>
>     lib.CreateContoso.restype = ContosoHandle
>     lib.DestroyContoso.argtypes = (ContosoHandle,)
>
> ctypes will raise an ArgumentError if DestroyContoso is called with
> arguments such as 123456789 or "Crash Me".

After typing up a response with all the detail, your reply helped me see
the error.

Thank you so much for all that detail, it was very much appreciated!
jlc