golang.org/x/sys v0.0.0-20200323222414-85ca7c5b95cd: unix.Getpid, unix.Uname, cpu.X86

Clean-room public code sample — generation instructions

Write a brand-new, minimal, self-contained code sample in this clean-room directory.
Do not copy, paraphrase, or reference any existing project source. Work only from this spec.

A csx.json manifest scaffold already exists. Do not recreate it from memory. Preserve its case.goal, packages and symbols; fill its empty case.contract with exact assertions and correct its environment, commands and verifierAdapter for the files you generate.

Goal: verify pkg:golang/golang.org/x/sys@v0.0.0-20200323222414-85ca7c5b95cd
Kind: HOW

Use EXACTLY these public packages and versions:
  - pkg:golang/golang.org/x/sys@v0.0.0-20200323222414-85ca7c5b95cd

Rules:
  - One focused purpose; the smallest project that proves the goal.
  - Include a contract test (test/contract.*) that runs OFFLINE and exits 0 exactly when the goal behavior works.
  - Pin every dependency with a lockfile so resolution is reproducible.
  - No secrets, credentials, or tokens. No real URLs (only example.com or localhost). No absolute paths.
  - No personal names, emails, company names, or project identifiers of any kind.
  - No binaries and no generated output (node_modules, dist, target, venv, .git, .env).
  - Keep it under 200 files and 256KB packed.

{"case":{"caseId":"case:sha256:cd19f27a2890f498c4ee1326f8e68910b92865429a66e88cd54c4cbb6081b1f2","contract":["unix.Getpid returns a positive integer equal to os.Getpid within the calling process","unix.Uname populates a unix.Utsname struct with non-empty Sysname, Machine, and Release fields and returns nil error","cpu.X86 exposes x86/amd64 CPU feature flag fields such as HasSSE2"],"goal":"verify pkg:golang/golang.org/x/sys@v0.0.0-20200323222414-85ca7c5b95cd","kind":"HOW","packages":["pkg:golang/golang.org/x/sys@v0.0.0-20200323222414-85ca7c5b95cd"],"schemaVersion":1,"symbols":["unix.Getpid","unix.Uname","cpu.X86"]},"contractCommand":["go","run","./test"],"environment":{"arch":"x64","distro":"ubuntu","ecosystem":"golang","libc":"glibc","libcVersion":"2.39","os":"linux","osVersionBucket":"24","packageManager":"go","schemaVersion":1},"license":"MIT-0","packages":["pkg:golang/golang.org/x/sys@v0.0.0-20200323222414-85ca7c5b95cd"],"schemaVersion":1,"subject":"pkg:golang/golang.org/x/sys@v0.0.0-20200323222414-85ca7c5b95cd","symbols":["unix.Getpid","unix.Uname","cpu.X86"],"verifierAdapter":"golang@1"}

module example.com/sample

go 1.21

require golang.org/x/sys v0.0.0-20200323222414-85ca7c5b95cd

golang.org/x/sys v0.0.0-20200323222414-85ca7c5b95cd h1:xhmwyvizuTgC2qz7ZlMluP20uW+C3Rm0FD/WLDX8884=
golang.org/x/sys v0.0.0-20200323222414-85ca7c5b95cd/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=

{
  "schemaVersion": 1,
  "goal": "verify pkg:golang/golang.org/x/sys@v0.0.0-20200323222414-85ca7c5b95cd",
  "kind": "HOW",
  "packages": [
    "pkg:golang/golang.org/x/sys@v0.0.0-20200323222414-85ca7c5b95cd"
  ]
}

package main

import (
	"bytes"
	"fmt"
	"os"

	"golang.org/x/sys/cpu"
	"golang.org/x/sys/unix"
)

func cstr(b []byte) string {
	idx := bytes.IndexByte(b, 0)
	if idx < 0 {
		return string(b)
	}
	return string(b[:idx])
}

func main() {
	pid := unix.Getpid()
	if pid <= 0 || pid != os.Getpid() {
		fmt.Fprintf(os.Stderr, "unexpected pid: got %d, want %d\n", pid, os.Getpid())
		os.Exit(1)
	}

	var uts unix.Utsname
	if err := unix.Uname(&uts); err != nil {
		fmt.Fprintf(os.Stderr, "unix.Uname error: %v\n", err)
		os.Exit(1)
	}
	sysname := cstr(uts.Sysname[:])
	machine := cstr(uts.Machine[:])
	release := cstr(uts.Release[:])
	if sysname == "" || machine == "" || release == "" {
		fmt.Fprintf(os.Stderr, "expected non-empty utsname fields, got sysname=%q machine=%q release=%q\n", sysname, machine, release)
		os.Exit(1)
	}

	copyX86 := cpu.X86
	copyX86.HasSSE2 = true
	if !copyX86.HasSSE2 {
		fmt.Fprintln(os.Stderr, "expected copyX86.HasSSE2 to be true")
		os.Exit(1)
	}
}