When a thread touches such an object for the first time, a new thread-local __dict__ is created,
and the __init__ method is run.
But a thread switch can occur here; if the other thread touches the same object, it installs another
__dict__; when the first thread resumes, it updates the dictionary of the second...
This is the deep cause of the failures in test_multiprocessing involving "managers" objects.
Also a 2.5 backport candidate.
behaviours. I left the original test commented out (note
that that test came from #2702, which seems to have a
problem in FreeBSD and Windows, but not in Linux).
I included a new test, to watch over the now-broken
behaviour, I took it from #3179.
Some functions in the msvcrt module are skipped,
and socket.ioctl is enabled only when using a more recent Platform SDK.
(and yes, there are still companies that use a 10-years old compiler)
Added checks for integer overflows, contributed by Google. Some are
only available if asserts are left in the code, in cases where they
can't be triggered from Python code.
occurances of PyBytes_ in the code to their original PyString_ names. The
bytesobject.c file will be renamed back to stringobject.c in a future checkin.
ctypes maintains thread-local storage that has space for two error
numbers: private copies of the system 'errno' value and, on Windows,
the system error code accessed by the GetLastError() and
SetLastError() api functions.
Foreign functions created with CDLL(..., use_errno=True), when called,
swap the system 'errno' value with the private copy just before the
actual function call, and swapped again immediately afterwards. The
'use_errno' parameter defaults to False, in this case 'ctypes_errno'
is not touched.
On Windows, foreign functions created with CDLL(...,
use_last_error=True) or WinDLL(..., use_last_error=True) swap the
system LastError value with the ctypes private copy.
The values are also swapped immeditately before and after ctypes
callback functions are called, if the callbacks are constructed using
the new optional use_errno parameter set to True: CFUNCTYPE(...,
use_errno=TRUE) or WINFUNCTYPE(..., use_errno=True).
New ctypes functions are provided to access the ctypes private copies
from Python:
- ctypes.set_errno(value) and ctypes.set_last_error(value) store
'value' in the private copy and returns the previous value.
- ctypes.get_errno() and ctypes.get_last_error() returns the current
ctypes private copies value.