Repository navigation
Process creation after debugging session not possible: teardown needed #2014
Description
Environment data
- debugpy version: latest
- OS and version: Windows 11
- Python version 314 (but issue is not python-version related)
- Using VS Code
Actual behavior
Connect to VSCode. Then apply
test = subprocess.Popen(
["C:\Python314\python.exe", "-c", "import sys; sys.exit(0)"],
creationflags=creationflags,
)
test.wait()
print(test.returncode)
this does not work because subprocess was patched. Also not after teardown of the debugging session:
from debugpy._vendored.pydevd.pydevd import stoptrace
stoptrace() to continue running the process. Now, subprocess.popen() does not work any more at al.
.... still subprocess.Popen will not work
Expected behavior
subprocess.Popen() should work
Steps to reproduce:
After debugging started, the following won't work. Make sure NOT to issue
debugpy.configure(subProcess=False) in order to reproduce this:
test = subprocess.Popen(
["C:\Python314\python.exe", "-c", "import sys; sys.exit(0)"],
creationflags=creationflags,
)
test.wait()
print(test.returncode)
SOLUTION
pydevd's patch_new_process_functions() patches _winapi.CreateProcess to intercept child process creation for subprocess debugging, but stoptrace() never unpatches it.
The effect is that you can't spawn processes after a debugging session is torn down and you want to resume your program without restart. The solution is a restoration on teardown:
from debugpy._vendored.pydevd.pydevd import stoptrace
stoptrace()
debugpy.server.api.listen.called = False # reset state so it can reconnect later
try:
import _winapi as _subprocess
except ImportError:
import _subprocess
if hasattr(_subprocess, 'original_CreateProcess'):
_subprocess.CreateProcess = _subprocess.original_CreateProcess
del _subprocess.original_CreateProcess
Activity
rchiodo commentedon Mar 23, 2026
I think what you're suggesting is that if this code was done at detach:
It would work?
Lexcon commentedon Mar 23, 2026