shoney.arickathil
6e997759e5
- five stories status: done; 00-story records the one-run landing - spec History: three implementation amendments (Signal record not scalar, caller-owned stdio fds, handler-latch instead of signalfd) - board NEXT PLAN entry with measured findings (zero transport code added; the tty-across-the-socket handover proven; the double-raw refusal restoring the terminal — the "bug" that was the design working); section rows flipped; graph nodes green - CODE-LOGIC.md: the runtime-v2 section - full belt quoted on the board: suites 0 fail both flavors (test_proc 193/0, test_term 60/0), woc 557/0, subprocess 12/0, site 23/0 Co-Authored-By: Claude Fable 5 <noreply@anthropic.com> (cherry picked from commit bc1b4f070693eb755ad6a9fd0c853fb3e2bda347)
2.4 KiB
| track | iteration | status | readiness |
|---|---|---|---|
| runtime-v2 | 3 | done | ready |
runtime-v2 3 — signals as events: SIGWINCH into a mailbox
Part of Story — runtime-v2: the runtime beyond sockets. The seam iteration 42 deliberately deferred "to its real consumer" — this is that consumer arriving. A terminal application's resize IS a signal (SIGWINCH), and nothing today can turn a signal into anything a program observes except the SIGTERM/SIGINT stop latch.
The problem. Signals are process-global, delivered on an arbitrary thread, and allowed to do almost nothing — the exact opposite of a shard-owned mailbox message. The runtime already crossed this bridge once: the stop flag is a signal made safe by latching. This iteration generalizes that shape without handing user code a signal handler.
Info — the forks, settled (brainstorm 2026-09-01; spec:
2026-09-01-runtime-v2-design.md)
signal.on(sig, addr)— a standing subscription delivering the SIGNAL NUMBER as a scalar message. No moved-message ownership rules: scalars copy, so a repeating SIGWINCH needs no per-delivery payload.- signalfd on shard 0's plane — one more registered fd with a
sentinel
user_data(the wake-eventfd precedent); reads drainsignalfd_siginforecords and fan out ordinary sends. - Offerable set: SIGWINCH, SIGCHLD, SIGHUP, SIGUSR1, SIGUSR2. SIGTERM/SIGINT registration is refused by name — the stop latch stays the engine's, iteration 40 is load-bearing.
- Coalescing disclosed, not sequenced — what SIGWINCH consumers expect anyway.
Also settled: this iteration is STANDALONE — the old edge from PTY was only the resize pairing; signalfd needs nothing from iteration 2.
Acceptance sketch
- Resize the controlling terminal of a test child: the registered actor receives the message; the grid-owning code calls 2's resize onward — the wmux wiring, proven in miniature.
- SIGCHLD registration does not disturb 42's pidfd machinery (they coexist; the pidfd stays the reap path).
- SIGTERM still stops the engine with the full drain — the iteration 40 battery unchanged.
Consumers
wmux 1 (SIGWINCH fan-out to panes). Everything else can wait — this iteration exists exactly once a real consumer does, per 42's deferral.