bpo-35797: Fix default executable used by the multiprocessing module (GH-11676)
(cherry picked from commit 4e02f8f8b4baab63f927cfd87b401200ba2969e9)
Co-authored-by: Steve Dower <steve.dower@microsoft.com>
diff --git a/Lib/multiprocessing/spawn.py b/Lib/multiprocessing/spawn.py
index 1f4f3f4..693f2fb 100644
--- a/Lib/multiprocessing/spawn.py
+++ b/Lib/multiprocessing/spawn.py
@@ -29,12 +29,19 @@
if sys.platform != 'win32':
WINEXE = False
WINSERVICE = False
+ _WINENV = False
else:
- WINEXE = (sys.platform == 'win32' and getattr(sys, 'frozen', False))
+ WINEXE = getattr(sys, 'frozen', False)
WINSERVICE = sys.executable.lower().endswith("pythonservice.exe")
+ _WINENV = '__PYVENV_LAUNCHER__' in os.environ
if WINSERVICE:
_python_exe = os.path.join(sys.exec_prefix, 'python.exe')
+elif _WINENV:
+ # bpo-35797: When running in a venv, we need to bypass the redirect
+ # executor and launch our base Python.
+ import _winapi
+ _python_exe = _winapi.GetModuleFileName(0)
else:
_python_exe = sys.executable