retoorandClaude Sonnet 5
9dbd1fe667
- Plexer: always-active terminal multiplexing. NativePlexerController/ TmuxPlexerController share one interface, chosen by which env var is already set (TAI_PLEXER_SOCKET vs TMUX_PANE); NativePlexerBackend is the pty.fork()-based wrapper (raw mode, SIGWINCH resize forwarding, a Unix-socket control protocol, continuous session logging, a Ctrl+A prefix key distinct from tmux's own Ctrl+B). Auto-wraps new interactive shells via a .bashrc hook mirroring the existing command-not-found install pattern, gated on $TMUX/$TAI_PLEXER_ACTIVE/ a $HOME/.tai-no-plexer bypass. New plexer_send/read/type/status tools, env-gated on a detected controller. - tests/container.py + docker-compose.yml + tests/docker/Dockerfile: a disposable podman/docker image for the tests that must never touch a real machine (installing the plexer hook into a real ~/.bashrc, a live tmux session). Required suite (test_seal.py, test_tai.py, tests/plexer.py, tests/bashrc.py) gates the result; tests/rag.py runs as best-effort since its real-LLM dependency can't be satisfied inside a disposable container with no nested engine. - tests/bashrc.py: real end-to-end hook install + bash -i auto-wrap, anti-recursion, tmux-active skip, non-interactive skip, a live TmuxPlexerController test, and an install/uninstall round-trip. - tests/plexer.py: NativePlexerBackend under a real pty, plus a dedicated robustness pass (file permissions, >64KB payload framing, a malformed control request, a genuine self-deadlock fix in the write-to-child path). - tai_test.py: the shared async process-driving framework (pipe/pty transport, group-wide kill-and-reap, a StdinBridge for --interactive) both test files build on. - ChatClient last-resort backend: when there's no local opencode CLI but the sandbox box is already running, install opencode into it (official Node tarball, not apt -- apt's nodejs/npm pull in webpack/babel/jest as transitive deps) and route through it instead of giving up. Only reachable after the first retry round already failed everything else; never creates the box itself. TmuxPlexerController.status() fixed to use `list-panes` instead of `display-message -p`, which silently fell back to the default pane instead of erroring against a dead target. - Fix 4 pre-existing test_tai.py bugs surfaced by running it in a clean environment for the first time: two stale mock signatures (subprocess.run's stdout= kwarg, Chat.complete's deadline= kwarg), one $TMUX-dependent catalog assertion, one tty-dependent color assertion. - research/: a sourced research archive (Source Dossier/Citation Card/Conclusion tiers) backing the above design decisions, with its own audit.py consistency checker. - .gitignore: fix a blanket *.md rule that was about to silently drop the entire research/ archive from version control; add __pycache__/ and the one-off debug transcript this session started from. Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
51 lines
3.0 KiB
Markdown
51 lines
3.0 KiB
Markdown
# Ptyprocess — Ptyprocess 0.7 documentation
|
|
|
|
## Metadata
|
|
|
|
| Field | Value |
|
|
|---|---|
|
|
| Institute | Molodetz Institute — Research & Retrieval Division |
|
|
| Subject | async-pty-process-testing |
|
|
| Document type | Source Dossier |
|
|
| Tier | 1 |
|
|
| Source title | Ptyprocess — Ptyprocess 0.7 documentation |
|
|
| Source URL | https://ptyprocess.readthedocs.io/en/latest/ |
|
|
| Source publisher / author | ptyprocess maintainers (readthedocs project) |
|
|
| Source type | vendor docs |
|
|
| Source date (published) | Unknown — not stated |
|
|
| Date researched | 2026-10-09 |
|
|
| Researched by | tai (agent), model: Claude Sonnet 5, on behalf of retoor |
|
|
| Research method | web search synthesis |
|
|
| Confidence | Medium |
|
|
| Status | Active |
|
|
|
|
## Summary
|
|
|
|
Ptyprocess is a Python library for spawning a child process attached to a real pseudo-terminal (pty) rather than plain pipes. Its documentation describes the behavioral guarantees a real pty gives you that a pipe cannot: unified stdio, window-size tracking with SIGWINCH delivery, and line-discipline signal generation (Ctrl-C becomes SIGINT).
|
|
|
|
## Key findings
|
|
|
|
- When a program runs under ptyprocess, all three of its standard streams (stdin/stdout/stderr) are connected to a single pty, not three separate pipes.
|
|
- Ptyprocess tracks the terminal's window size and notifies the child process with a SIGWINCH signal when it changes.
|
|
- In cooked (line-buffered) terminal mode, the kernel's tty line discipline turns a Ctrl-C keystroke (byte 0x03) into a SIGINT delivered to the foreground process group — this only happens because the device is a real pty, not a pipe.
|
|
|
|
## Pros / strengths
|
|
|
|
- Documents, in one place, exactly which "feels like a real terminal" behaviors a pty provides that a pipe does not — this is the core justification for why `tai_test.py` needed pty support at all, since `tai.py`'s own code branches on `sys.stdin.isatty()`.
|
|
- The SIGWINCH and line-discipline-SIGINT points are concrete, testable claims, not vague marketing.
|
|
|
|
## Cons / limitations / caveats
|
|
|
|
- The dossier is based on a web-search synthesis of the documentation, not a full read of the library's source or a hands-on trial of ptyprocess itself — `tai_test.py` does not depend on ptyprocess as a library, only on the general pty behavior it documents (which was reimplemented directly against the stdlib `pty` module).
|
|
- Says nothing about asyncio integration; ptyprocess itself is a synchronous/blocking library.
|
|
|
|
## Relevance to tai
|
|
|
|
Directly informed the decision to give `tai_test.py`'s pty mode a real pseudo-terminal rather than a pipe, since `tai.py` branches on `isatty()` for approval prompts and readline behavior. The SIGWINCH/Ctrl-C-SIGINT behaviors this source describes are explicitly **not** relied on by `tai_test.py` — see the companion dossier on the `start_new_session`/controlling-terminal pitfall (`github-agents-issue1-controlling-terminal.md`) and the framework's own documented limitation in its module docstring.
|
|
|
|
## Changelog
|
|
|
|
| Date | Change |
|
|
|---|---|
|
|
| 2026-10-09 | Initial dossier created. |
|