golang.org/x/sys v0.41.0: unix.Nanosleep

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.Nanosleep in pkg:golang/golang.org/x/sys@v0.41.0
Kind: HOW

Use EXACTLY these public packages and versions:
  - pkg:golang/golang.org/x/sys@v0.41.0
Demonstrate these symbols/APIs:
  - golang.org/x/sys/unix.Nanosleep

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:sha256:22fb540f621203be852a329c986b520466a0fec8cde0aacb070292297c5fb930","contract":["unix.Nanosleep suspends execution for at least the specified duration when given a valid Timespec","unix.Nanosleep with zero duration returns nil error immediately","unix.Nanosleep accepts a non-nil leftover Timespec pointer on normal completion","unix.Nanosleep returns EINVAL when Nsec is out of the valid range [0, 999999999]","unix.Nanosleep returns EINVAL when Sec is negative"],"goal":"verify golang.org/x/sys/unix.Nanosleep in pkg:golang/golang.org/x/sys@v0.41.0","kind":"HOW","packages":["pkg:golang/golang.org/x/sys@v0.41.0"],"schemaVersion":1,"symbols":["golang.org/x/sys/unix.Nanosleep"]},"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@v0.41.0"],"schemaVersion":1,"subject":"pkg:golang/golang.org/x/sys@v0.41.0","symbols":["golang.org/x/sys/unix.Nanosleep"],"verifierAdapter":"golang@1"}

module sample

go 1.25.0

require golang.org/x/sys v0.41.0 // indirect

golang.org/x/sys v0.41.0 h1:Ivj+2Cp/ylzLiEU89QhWblYnOE9zerudt9Ftecq2C6k=
golang.org/x/sys v0.41.0/go.mod h1:OgkHotnGiDImocRcuBABYBEXf8A9a87e/uXjp9XT3ks=

package main

import (
	"fmt"
	"os"
	"time"

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

// SleepNanosleep pauses the current goroutine/thread for the given duration
// using the low-level unix.Nanosleep syscall.
func SleepNanosleep(d time.Duration) error {
	ts := unix.NsecToTimespec(d.Nanoseconds())
	return unix.Nanosleep(&ts, nil)
}

func main() {
	fmt.Println("Demonstrating unix.Nanosleep...")

	sleepDuration := 50 * time.Millisecond
	start := time.Now()

	if err := SleepNanosleep(sleepDuration); err != nil {
		fmt.Fprintf(os.Stderr, "unix.Nanosleep failed: %v\n", err)
		os.Exit(1)
	}

	elapsed := time.Since(start)
	fmt.Printf("Successfully slept for %v (requested: %v)\n", elapsed, sleepDuration)
}

{
  "schemaVersion": 1,
  "goal": "verify golang.org/x/sys/unix.Nanosleep in pkg:golang/golang.org/x/sys@v0.41.0",
  "kind": "HOW",
  "packages": [
    "pkg:golang/golang.org/x/sys@v0.41.0"
  ],
  "symbols": [
    "golang.org/x/sys/unix.Nanosleep"
  ]
}

package main

import (
	"errors"
	"fmt"
	"os"
	"time"

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

func main() {
	// Assertion 1: unix.Nanosleep suspends execution for at least the specified duration when given a valid Timespec
	req := &unix.Timespec{Sec: 0, Nsec: 20_000_000} // 20ms
	start := time.Now()
	if err := unix.Nanosleep(req, nil); err != nil {
		fmt.Fprintf(os.Stderr, "FAIL: unix.Nanosleep failed for valid duration: %v\n", err)
		os.Exit(1)
	}
	elapsed := time.Since(start)
	if elapsed < 15*time.Millisecond {
		fmt.Fprintf(os.Stderr, "FAIL: unix.Nanosleep slept for less than expected: %v\n", elapsed)
		os.Exit(1)
	}

	// Assertion 2: unix.Nanosleep with zero duration returns nil error immediately
	zeroReq := &unix.Timespec{Sec: 0, Nsec: 0}
	start = time.Now()
	if err := unix.Nanosleep(zeroReq, nil); err != nil {
		fmt.Fprintf(os.Stderr, "FAIL: unix.Nanosleep failed for zero duration: %v\n", err)
		os.Exit(1)
	}
	if elapsed := time.Since(start); elapsed > 500*time.Millisecond {
		fmt.Fprintf(os.Stderr, "FAIL: unix.Nanosleep with zero duration took too long: %v\n", elapsed)
		os.Exit(1)
	}

	// Assertion 3: unix.Nanosleep accepts a non-nil leftover Timespec pointer on normal completion
	var rem unix.Timespec
	remReq := &unix.Timespec{Sec: 0, Nsec: 5_000_000} // 5ms
	if err := unix.Nanosleep(remReq, &rem); err != nil {
		fmt.Fprintf(os.Stderr, "FAIL: unix.Nanosleep with leftover pointer failed: %v\n", err)
		os.Exit(1)
	}

	// Assertion 4: unix.Nanosleep returns EINVAL when Nsec is out of the valid range [0, 999999999]
	invalidNsecNegative := &unix.Timespec{Sec: 0, Nsec: -1}
	if err := unix.Nanosleep(invalidNsecNegative, nil); !errors.Is(err, unix.EINVAL) {
		fmt.Fprintf(os.Stderr, "FAIL: expected EINVAL for negative Nsec, got: %v\n", err)
		os.Exit(1)
	}
	invalidNsecTooLarge := &unix.Timespec{Sec: 0, Nsec: 1_000_000_000}
	if err := unix.Nanosleep(invalidNsecTooLarge, nil); !errors.Is(err, unix.EINVAL) {
		fmt.Fprintf(os.Stderr, "FAIL: expected EINVAL for Nsec >= 1e9, got: %v\n", err)
		os.Exit(1)
	}

	// Assertion 5: unix.Nanosleep returns EINVAL when Sec is negative
	invalidSecNegative := &unix.Timespec{Sec: -1, Nsec: 0}
	if err := unix.Nanosleep(invalidSecNegative, nil); !errors.Is(err, unix.EINVAL) {
		fmt.Fprintf(os.Stderr, "FAIL: expected EINVAL for negative Sec, got: %v\n", err)
		os.Exit(1)
	}

	fmt.Println("PASS: all contract assertions passed")
}