Make child-process tests portable across operating systems

[AlexeyKuznetsov-DD]

What Does This Do

Adds PortableCommand so tests can run echo, cat, sleep, and a non-terminating command without OS-specific call sites. POSIX keeps native utilities; Windows uses a small child JVM.

Migrates ProcessSupervisorTest and ShellCommandExecutorTest to the portable commands.

Motivation

Make child-process tests OS-independent without relying on Windows shell builtins or changing existing POSIX behavior.

Additional Notes

Validated the helper on the default JVM and Java 8, plus both migrated test classes: 43 focused test executions passed.

Contributor Checklist

• Format the title according to the contribution guidelines
• Assign the type: and (comp: or inst:) labels in addition to any other useful labels
• Avoid using close, fix, or any linking keywords when referencing an issue
  Use solves instead, and assign the PR milestone to the issue
• Update the CODEOWNERS file on source file addition, migration, or deletion
• Update public documentation with any new configuration flags or behaviors
• Once approved, use merge queue to merge the PR

Jira ticket: N/A

[dd-octo-sts]

🟢 Java Benchmark SLOs — All performance SLOs passed

Suite	Status
Startup	🟢 pass

SLO thresholds are defined here based on automatically generated metrics. A warning is raised when results are within 5% of the threshold.

PR vs. master results

Scenario	Candidate	master	Δ (95% CI of mean)
startup:insecure-bank:iast:Agent	14.74 s	14.64 s	[-0.2%; +1.6%] (no difference)
startup:insecure-bank:tracing:Agent	13.57 s	13.66 s	[-1.3%; +0.0%] (no difference)
startup:petclinic:appsec:Agent	15.73 s	16.73 s	[-11.3%; -0.6%] (unstable)
startup:petclinic:iast:Agent	16.88 s	16.89 s	[-0.8%; +0.7%] (no difference)
startup:petclinic:profiling:Agent	16.50 s	16.87 s	[-3.4%; -1.0%] (maybe better)
startup:petclinic:sca:Agent	16.90 s	16.67 s	[+0.4%; +2.3%] (maybe worse)
startup:petclinic:tracing:Agent	16.04 s	16.10 s	[-1.4%; +0.7%] (no difference)

Commit: 0d673408 · CI Pipeline · Benchmarking Platform UI

---

Load and DaCapo benchmarks can be triggered manually in the GitLab pipeline. Results will appear in the Benchmarking Platform UI after completion.

[chatgpt-codex-connector]

Codex Review Summary

This comment shows the latest Codex review activity on this pull request.

Review	Status	Commit	Review trigger
📝 Code Review	✅ Completed 2026-09-01T23:16:44.721286Z	2562626	Draft marked ready

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[chatgpt-codex-connector]

💡 Codex Review

Here are some automated review suggestions for this pull request.

Reviewed commit: 256262607b

ℹ️ About Codex in GitHub

Your team has set up Codex to review pull requests in this repo. Reviews are triggered when you

• Open a pull request for review
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• Comment "@codex review".

If Codex has suggestions, it will comment; otherwise it will react with 👍.

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[datadog-prod-us1-6]

The new echo helper changes valid values across operating systems. POSIX treats option-like values as flags, and Windows can write non-ASCII text in a charset that the migrated consumer does not use.

_{Open Bits AI session}

_{🤖 Datadog Autotest · Commit 2562626 · What is Autotest? · @DataDog review to ask questions · Any feedback? Reach out in #autotest}

[dougqh]

I see the bots have a few suggestions, but overall, this looks good to me.

[AlexeyKuznetsov-DD]

I see the bots have a few suggestions, but overall, this looks good to me.

Yep, I will process suggestions from bot before merge.