Files
hermes-agent/tests/tools
teknium1 7ce6b504a2 fix(process_registry): use taskkill /T /F for tree-kill on Windows
The Windows branch of `_terminate_host_pid` early-returned after
`os.kill(pid, SIGTERM)` (which Python maps to `TerminateProcess` for
the target handle only), leaving descendant processes — e.g. Chromium
renderer/GPU/network helpers spawned by an `agent-browser` daemon —
running on Windows even after the preceding commit fixed POSIX.

The right Windows primitive is `taskkill /PID <pid> /T /F`:
`/T` walks the tree, `/F` force-terminates. Same approach
`gateway.status.terminate_pid(force=True)` already uses for the
gateway's own shutdown path; reuse the same shape here.

Why NOT extend the POSIX psutil tree-walk to Windows:

  1. Windows doesn't maintain a Unix-style process tree. `psutil.
     Process.children(recursive=True)` walks PPID links that go stale
     when intermediate processes exit, so enumeration is best-effort
     and silently misses orphaned descendants. The whole bug we're
     fixing is orphaned descendants.

  2. `psutil.Process.terminate()` on Windows is `TerminateProcess()`
     for one handle — same single-PID scope as the existing
     `os.kill`. The existing comment in `gateway/status.py::
     terminate_pid` warns this explicitly: 'os.kill SIGTERM is not
     equivalent to a tree-killing hard stop' on Windows.

  3. Headless Chromium has no GUI window, so the softer
     `taskkill /T` without `/F` (which sends WM_CLOSE) won't reach
     it either. `/F` is required.

POSIX path is unchanged. The taskkill subprocess uses the same
`creationflags=windows_hide_flags()` pattern other Windows shellouts
in this codebase use. `FileNotFoundError` / `TimeoutExpired` /
`OSError` fall back to bare `os.kill(SIGTERM)` as cheap insurance.

Tests cover the Windows branch via the codebase's standard
`monkeypatch _IS_WINDOWS` pattern (`references/windows-native-
support.md`), plus POSIX tree-walk order, NoSuchProcess swallow,
and the OSError fallback path. 7 new tests, all green on Linux CI.
2026-05-23 20:30:29 -07:00
..