Per contract §0 ("if this doc disagrees with the code, the code
wins; fix it in the same PR"), fold the step-0 probe results and
the as-landed impl back into `01_tipc_backend.md`.
Settled the two claims §9 flagged as unverified,
- `SO_ACCEPTCONN` on `AF_TIPC` **works** (answers `1`); we never
needed trio's `except OSError` carve-out.
- dup-name bind → **silent crosstalk is real**: both binds
succeed and dials alternate strictly, so a `.get_random()`
clash is never `EADDRINUSE`.
Corrections where the plan was wrong,
- §5.2's `tipc_event` is **48B not 40B** (`4+4+4+8+28`), and
python exposes `TIPC_WAIT_FOREVER` as `-1` so it needs masking
before packing as `'I'`.
- §7.2's pytest mark goes in `_testing/pytest.py::
pytest_configure()`, NOT `pyproject.toml` — the repo has no
`markers` ini table.
- §7.4's "10k → 10k distinct" is a ~1.2% flaky assert by
birthday bound on a 32b instance space; use `>= n-2` w/ the
arithmetic documented.
- §2.2's `unwrapped_type` and §3.2's `from_addr()` sketch still
showed the 2-tuple + the `'tipc:<stype>:<scope>'` prefix hack
that §2.2 itself had already withdrawn.
Two hazards the plan never anticipated, now recorded in §9,
- an unpublished-name dial answers `EHOSTUNREACH` which python
maps to a **bare `OSError`**, NOT a `ConnectionError` subtype,
so the `_reraise_as_connerr()` wrap is contract-§4 mandatory.
- a connect-then-drop peer answers `ENOTCONN` from
`getpeername()`, which — since `.get_stream_addrs()` runs
BEFORE the handshake — used to kill the whole actor.
Also withdraw §9's "fold a 6-byte digest into `(stype_low,
instance)`" escalation: varying `_stype` per-actor would need
65536 topology subscriptions and kills layer B outright.
(this patch was generated in some part by `claude-code` using `claude-opus-5` (`anthropic`))
Gud Boi
7e20585f59