Make __mp_main__ an alias for __main__ in all processes to simplify
pickling of classes defined in main module.
diff --git a/Lib/multiprocessing/__init__.py b/Lib/multiprocessing/__init__.py
index 1f3e67c..efad532 100644
--- a/Lib/multiprocessing/__init__.py
+++ b/Lib/multiprocessing/__init__.py
@@ -40,6 +40,13 @@
from multiprocessing.util import SUBDEBUG, SUBWARNING
#
+# Alias for main module -- will be reset by bootstrapping child processes
+#
+
+if '__main__' in sys.modules:
+ sys.modules['__mp_main__'] = sys.modules['__main__']
+
+#
# Exceptions
#
diff --git a/Lib/multiprocessing/forking.py b/Lib/multiprocessing/forking.py
index af6580d..fe4ee33 100644
--- a/Lib/multiprocessing/forking.py
+++ b/Lib/multiprocessing/forking.py
@@ -441,27 +441,17 @@
dirs = [os.path.dirname(main_path)]
assert main_name not in sys.modules, main_name
+ sys.modules.pop('__mp_main__', None)
file, path_name, etc = imp.find_module(main_name, dirs)
try:
- # We would like to do "imp.load_module('__main__', ...)"
- # here. However, that would cause 'if __name__ ==
- # "__main__"' clauses to be executed.
+ # We should not do 'imp.load_module("__main__", ...)'
+ # since that would execute 'if __name__ == "__main__"'
+ # clauses, potentially causing a psuedo fork bomb.
main_module = imp.load_module(
- '__parents_main__', file, path_name, etc
+ '__mp_main__', file, path_name, etc
)
finally:
if file:
file.close()
- sys.modules['__main__'] = main_module
- main_module.__name__ = '__main__'
-
- # Try to make the potentially picklable objects in
- # sys.modules['__main__'] realize they are in the main
- # module -- somewhat ugly.
- for obj in list(main_module.__dict__.values()):
- try:
- if obj.__module__ == '__parents_main__':
- obj.__module__ = '__main__'
- except Exception:
- pass
+ sys.modules['__main__'] = sys.modules['__mp_main__'] = main_module