---
model: gpt-5.6-sol
service: opencode
timestamp: 2026-08-28T04:51:19Z
git_ref: fb6d81d3
diff_cmd: git diff HEAD~1..HEAD
---

# Raw output - detect child death before parent handshake

The human asked to continue WireGuard Layer C after child entrypoints
learned to consume inherited network namespace capabilities.

## Generated code

> `git diff HEAD~1..HEAD -- tractor/spawn/_spawn.py tractor/spawn/_trio.py tests/test_spawning.py`

Race a spawned child's initial parent handshake against its process
wait operation. Return the established channel when the handshake wins;
raise `ActorFailure` with the exit status when the process dies first.
Use the race in the Trio exec backend instead of waiting indefinitely
on `IPCServer.wait_for_peer()`.

Add deterministic Trio tests for handshake-first, death-first,
simultaneous, and waiter-error schedules, controlling readiness with
events rather than sleeps. Exercise the full Trio backend with a fake
dead process to prove pre-publication event registration and exact
failed-startup cleanup.

## Scope boundary

This prerequisite prevents pre-connection namespace-entry failures
from hanging their parent. Namespace FD transfer itself remains the
next commit.