tractor/tractor/spawn
Gud Boi 16402164cc Scaffold `child_sigint` modes for forkserver
Add configuration surface for future child-side SIGINT
plumbing in `subint_forkserver_proc` without wiring up the
actual trio-native SIGINT bridge — lifting one entry-guard
clause will flip the `'trio'` branch live once the
underlying fork-prelude plumbing is implemented.

Deats,
- new `ChildSigintMode = Literal['ipc', 'trio']` type +
  `_DEFAULT_CHILD_SIGINT = 'ipc'` module-level default.
  Docstring block enumerates both:
  - `'ipc'` (default, currently the only implemented mode):
    no child-side SIGINT handler — `trio.run()` is on the
    fork-inherited non-main thread where
    `signal.set_wakeup_fd()` is main-thread-only, so
    cancellation flows exclusively via the parent's
    `Portal.cancel_actor()` IPC path. Known gap: orphan
    children don't respond to SIGINT
    (`test_orphaned_subactor_sigint_cleanup_DRAFT`)
  - `'trio'` (scaffolded only): manual SIGINT → trio-cancel
    bridge in the fork-child prelude so external Ctrl-C
    reaches stuck grandchildren even w/ a dead parent
- `subint_forkserver_proc` pulls `child_sigint` out of
  `proc_kwargs` (matches how `trio_proc` threads config to
  `open_process`, keeps `start_actor(proc_kwargs=...)` as
  the ergonomic entry point); validates membership + raises
  `NotImplementedError` for `'trio'` at the backend-entry
  guard
- `_child_target` grows a `match child_sigint:` arm that
  slots in the future `'trio'` impl without restructuring
  — today only the `'ipc'` case is reachable
- module docstring "Still-open work" list grows a bullet
  pointing at this config + the xfail'd orphan-SIGINT test

No behavioral change on the default path — `'ipc'` is the
existing flow. Scaffolding only.

(this patch was generated in some part by [`claude-code`][claude-code-gh])
[claude-code-gh]: https://github.com/anthropics/claude-code

(cherry picked from commit dcd5c1ff40)
2026-06-24 19:54:25 -04:00
..
__init__.py Restore fn-arg `_runtime_vars` in `trio_proc` teardown 2026-04-23 18:30:11 -04:00
_entry.py Tidy `spawn/` subpkg docstrings and imports 2026-04-17 19:03:00 -04:00
_forkserver_override.py Mv core mods to `runtime/`, `spawn/`, `discovery/` subpkgs 2026-04-02 17:59:13 -04:00
_mp.py Tidy `spawn/` subpkg docstrings and imports 2026-04-17 19:03:00 -04:00
_mp_fixup_main.py Fix typos + typing in `_mp_fixup_main` 2026-04-10 20:58:54 -04:00
_reap.py Add `tractor.spawn._reap.unlink_uds_bind_addrs()` 2026-06-17 17:39:44 -04:00
_spawn.py Wire `subint_forkserver` as first-class backend 2026-06-24 19:54:25 -04:00
_subint.py Doc `subint_fork` as blocked by CPython post-fork 2026-06-24 19:54:25 -04:00
_subint_fork.py Doc `subint_fork` as blocked by CPython post-fork 2026-06-24 19:54:25 -04:00
_subint_forkserver.py Scaffold `child_sigint` modes for forkserver 2026-06-24 19:54:25 -04:00
_trio.py Add `tractor.spawn._reap.unlink_uds_bind_addrs()` 2026-06-17 17:39:44 -04:00