golang.org/x/sys v0.40.0: unix.NsecToTimeval

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 golang.org/x/sys/unix.NsecToTimeval in pkg:golang/golang.org/x/sys@v0.40.0
Kind: HOW

Use EXACTLY these public packages and versions:
  - pkg:golang/golang.org/x/sys@v0.40.0
Demonstrate these symbols/APIs:
  - golang.org/x/sys/unix.NsecToTimeval

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:sha256:727ede13fe56c8e9b5cb1ed7bdff58dccb74ee9acaeeb5ec9a0f5054cb55d226","contract":["unix.NsecToTimeval converts nanoseconds into a unix.Timeval struct with Sec and Usec fields","unix.NsecToTimeval handles zero nanoseconds resulting in zero Sec and Usec","unix.NsecToTimeval accurately splits subsecond and multi-second time intervals into seconds and microseconds"],"goal":"verify golang.org/x/sys/unix.NsecToTimeval in pkg:golang/golang.org/x/sys@v0.40.0","kind":"HOW","packages":["pkg:golang/golang.org/x/sys@v0.40.0"],"schemaVersion":1,"symbols":["golang.org/x/sys/unix.NsecToTimeval"]},"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@v0.40.0"],"schemaVersion":1,"subject":"pkg:golang/golang.org/x/sys@v0.40.0","symbols":["golang.org/x/sys/unix.NsecToTimeval"],"verifierAdapter":"golang@1"}

module example.com/sample

go 1.24.0

require golang.org/x/sys v0.40.0

golang.org/x/sys v0.40.0 h1:DBZZqJ2Rkml6QMQsZywtnjnnGvHza6BTfYFWY9kjEWQ=
golang.org/x/sys v0.40.0/go.mod h1:OgkHotnGiDImocRcuBABYBEXf8A9a87e/uXjp9XT3ks=

package main

import (
	"fmt"

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

// NanosecondsToTimeval converts an integer nanosecond count into a unix.Timeval.
func NanosecondsToTimeval(nsec int64) unix.Timeval {
	return unix.NsecToTimeval(nsec)
}

func main() {
	nanoseconds := int64(2500000000) // 2.5 seconds
	tv := NanosecondsToTimeval(nanoseconds)
	fmt.Printf("Nanoseconds: %d -> Timeval: {Sec: %d, Usec: %d}\n", nanoseconds, tv.Sec, tv.Usec)
}

{
  "schemaVersion": 1,
  "goal": "verify golang.org/x/sys/unix.NsecToTimeval in pkg:golang/golang.org/x/sys@v0.40.0",
  "kind": "HOW",
  "packages": [
    "pkg:golang/golang.org/x/sys@v0.40.0"
  ],
  "symbols": [
    "golang.org/x/sys/unix.NsecToTimeval"
  ]
}

package main

import (
	"fmt"
	"os"

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

func main() {
	// Assertion 1: unix.NsecToTimeval converts nanoseconds into a unix.Timeval struct with Sec and Usec fields
	nsec1 := int64(2500000000)
	tv1 := unix.NsecToTimeval(nsec1)
	if tv1.Sec != 2 || tv1.Usec != 500000 {
		fmt.Fprintf(os.Stderr, "FAIL: expected Sec=2, Usec=500000, got Sec=%d, Usec=%d\n", tv1.Sec, tv1.Usec)
		os.Exit(1)
	}

	// Assertion 2: unix.NsecToTimeval handles zero nanoseconds resulting in zero Sec and Usec
	tvZero := unix.NsecToTimeval(0)
	if tvZero.Sec != 0 || tvZero.Usec != 0 {
		fmt.Fprintf(os.Stderr, "FAIL: expected zero timeval, got %+v\n", tvZero)
		os.Exit(1)
	}

	// Assertion 3: unix.NsecToTimeval accurately splits subsecond and multi-second time intervals into seconds and microseconds
	tvSub := unix.NsecToTimeval(123456000)
	if tvSub.Sec != 0 || tvSub.Usec != 123456 {
		fmt.Fprintf(os.Stderr, "FAIL: expected Sec=0, Usec=123456, got %+v\n", tvSub)
		os.Exit(1)
	}

	tvMulti := unix.NsecToTimeval(10999999000)
	if tvMulti.Sec != 10 || tvMulti.Usec != 999999 {
		fmt.Fprintf(os.Stderr, "FAIL: expected Sec=10, Usec=999999, got %+v\n", tvMulti)
		os.Exit(1)
	}

	fmt.Println("PASS: unix.NsecToTimeval contract verified successfully")
}