Fixes#9559.
When `shell_snapshot` runs, it may execute user startup files (e.g.
`.bashrc`). If those files read from stdin (or if stdin is an
interactive TTY under job control), the snapshot subprocess can block or
receive `SIGTTIN` (as reported over SSH).
This change explicitly sets `stdin` to `Stdio::null()` for the snapshot
subprocess, so it can't read from the terminal.
Regression test added that would hang/timeout without this change.
Tests: `ulimit -n 4096 && cargo test -p codex-core`.
cc @dongdongbh @etraut-openai
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Co-authored-by: Skylar Graika <sgraika127@gmail.com>
## What
Record a model-visible `<turn_aborted>` marker in history when a turn is
interrupted, and treat it as a session prefix.
## Why
When a turn is interrupted, Codex emits `TurnAborted` but previously did
not persist anything model-visible in the conversation history. On the
next user turn, the model can’t tell the previous work was aborted and
may resume/repeat earlier actions (including duplicated side effects
like re-opening PRs).
Fixes: https://github.com/openai/codex/issues/9042
## How
On `TurnAbortReason::Interrupted`, append a hidden user message
containing a `<turn_aborted>…</turn_aborted>` marker and flush.
Treat `<turn_aborted>` like `<environment_context>` for session-prefix
filtering.
Add a regression test to ensure follow-up turns don’t repeat side
effects from an aborted turn.
## Testing
`just fmt`
`just fix -p codex-core`
`cargo test -p codex-core -- --test-threads=1`
`cargo test --all-features -- --test-threads=1`
---------
Co-authored-by: Skylar Graika <sgraika127@gmail.com>
Co-authored-by: jif-oai <jif@openai.com>
Co-authored-by: Eric Traut <etraut@openai.com>
