shoney.arickathil
ab8ef64cd9
- five stories under docs/stories/runtime-v2/: 1 streaming subprocess (42's follow-up; five forks incl. the mailbox-cap collision), 2 PTY, 3 signals-as-events (signalfd lean), 4 termios adoption, 5 SCM_RIGHTS fd passing; 00-story states the arc — the plane learned sockets in 8/11/35, files in 6, this adds processes/terminals/signals - build order 1 -> 2 -> 3; 4 and 5 startable alone; all readiness: refine, brainstormed on demand - board: Five tracks; "▸ runtime-v2" pending section; wmux section now points at it; graph section 6 nodes carry runtime-v2 numbers + links - wmux stories re-reference the track; prefix `rt2` claimed - linkcheck: 0 broken Co-Authored-By: Claude Fable 5 <noreply@anthropic.com> (cherry picked from commit e0451cb4889bb3d03429c0276d03c090269a5ced)
47 lines
1.9 KiB
Markdown
47 lines
1.9 KiB
Markdown
---
|
|
track: runtime-v2
|
|
iteration: "4"
|
|
status: pending
|
|
readiness: refine
|
|
---
|
|
|
|
# runtime-v2 4 — termios adoption: raw mode on a terminal we were given
|
|
|
|
> Part of [Story — runtime-v2: the runtime beyond sockets](00-story.md).
|
|
> No incoming edges — startable alone, any time.
|
|
>
|
|
> **The problem.** [2](02-pty.md) creates terminals for children; this
|
|
> adopts the one the PROCESS was given. A wmux client must put its own
|
|
> stdin into raw mode (no echo, no line buffering, keys arrive as they
|
|
> are typed) and — non-negotiably — restore it on every exit path,
|
|
> including a trap. A terminal left raw is the classic way a program
|
|
> makes a user's shell unusable.
|
|
|
|
## Info — the forks (open)
|
|
|
|
1. **Surface size.** Exactly two verbs — `term.raw()` returning a
|
|
restore token and `term.restore(token)` (the lean: wmux needs
|
|
nothing else; tmux itself uses little more than `cfmakeraw`) —
|
|
versus exposing termios flag knobs. YAGNI says two verbs and a
|
|
refusal for the rest.
|
|
2. **Restore guarantee.** Tie restoration to the unwind machinery (the
|
|
42 ownership pattern: fiber dies, terminal restored — a runtime
|
|
obligation) versus caller's-problem-with-a-doc-note. Lean: runtime
|
|
obligation; "no orphan" has a terminal-state sibling: no wrecked tty.
|
|
3. **Scope.** stdin only, versus any tty fd (a client adopting a tty it
|
|
received via [5](05-fd-passing.md) — the wmux SERVER's need). This
|
|
fork decides whether the verb takes an fd argument now or grows one
|
|
later.
|
|
|
|
## Acceptance sketch
|
|
|
|
- Raw on, keystroke arrives unbuffered and unechoed (driven under a
|
|
[2](02-pty.md) PTY in the test — the two iterations prove each other).
|
|
- Restore: `tcgetattr` before equals after, on the normal path AND after
|
|
a deliberate trap while raw.
|
|
- The stop path restores too — SIGTERM while raw leaves a sane terminal.
|
|
|
|
## Consumers
|
|
|
|
wmux 1's client half. The alacritty stage-A harness benefits but does
|
|
not require it.
|