[knihit]

Description

CLI:

• cli_self_update.rs: update --cli's smoke test now retries the exec of the freshly downloaded binary on ExecutableFileBusy (os error 26), instead of failing the update outright.

On Linux, fork() duplicates every file descriptor open anywhere in the process. If another thread forks while the downloaded binary's write handle is still open, the child inherits that handle and holds it until it execs or exits. Until then, exec of the binary fails with "Text file busy", even though the smoke test's own write handle closed well before the exec was attempted. This is a known class of race in the Rust standard library; see rust-lang/rust#114554.

The fix retries the spawn up to 10 times, 100ms apart (about 1 second total), but only when the failure is ExecutableFileBusy or raw os error 26. The retry loop lives in its own function with an injectable spawn/sleep seam, so a unit test can drive it deterministically with a fake exec that fails a set number of times then succeeds, without depending on reproducing the real race.

• Three new unit tests cover the retry: succeeds after a few failures, exhausts all 10 attempts and returns the error, and leaves a non-busy error untouched.
• Version bumped 1.0.3 -> 1.0.5 with a corresponding CHANGELOG.md entry.

Fixes # (issue)

Type of Change

• CLI (cli/) change — Rust

Testing

• If cli/ changed: cd cli && make test passes (Rust + Python + conformance suites)
• New or changed code files carry the required SPDX header (see AGENTS.md's License headers rule); formats without comment syntax (e.g. JSON) are exempt

Full cargo test passes locally: 1725 tests. Ran the full suite 15 times in a row at 64 threads to rule out flakiness from the timing-sensitive retry logic; all 15 runs were green.

Checklist

• My code follows the style guidelines of this project (see AGENTS.md's Code Style & Conventions)
• I have performed a self-review of my own changes
• I have commented my code where necessary
• I have made corresponding changes to the documentation
• My changes generate no new warnings — build is clean, and for cli/ changes, cd cli && make lint passes (cargo clippy -- -D warnings + cargo fmt --check)
• I have added or updated tests that prove my change works (see Testing above for the exact commands)

Agents Affected

None.

Notes for Reviewers

This only affects the self-update path on Linux, where it's possible for a concurrent fork elsewhere in the process to transiently hold the downloaded binary's file descriptor open. The retry window (about 1 second) is a judgment call: long enough to clear the race in practice, short enough that a genuinely broken binary still fails the update promptly.

[knihit]

The retry fix is now in #62, without the version bump. #62 also stops skipping the smoke test in CI.