golang.org/x/sys v0.24.0: unix.BytePtrToString

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.BytePtrToString in pkg:golang/golang.org/x/sys@v0.24.0
Kind: HOW

Use EXACTLY these public packages and versions:
  - pkg:golang/golang.org/x/sys@v0.24.0
Demonstrate these symbols/APIs:
  - golang.org/x/sys/unix.BytePtrToString

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:sha256:155baa321f74504b7c748d5deada56e6e10959f68cced09659285784a97e66fd","contract":["unix.BytePtrToString(nil) returns an empty string","unix.BytePtrToString returns an empty string when pointing directly to a NUL byte","unix.BytePtrToString converts a NUL-terminated byte sequence to a string and stops at the first NUL byte","unix.BytePtrToString converts a NUL-terminated slice offset pointer up to its NUL terminator"],"goal":"verify golang.org/x/sys/unix.BytePtrToString in pkg:golang/golang.org/x/sys@v0.24.0","kind":"HOW","packages":["pkg:golang/golang.org/x/sys@v0.24.0"],"schemaVersion":1,"symbols":["golang.org/x/sys/unix.BytePtrToString"]},"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@v0.24.0"],"schemaVersion":1,"subject":"pkg:golang/golang.org/x/sys@v0.24.0","symbols":["golang.org/x/sys/unix.BytePtrToString"],"verifierAdapter":"golang@1"}

module example.com/sample

go 1.22

require golang.org/x/sys v0.24.0

golang.org/x/sys v0.24.0 h1:Twjiwq9dn6R1fQcyiK+wQyHWfaz/BJB+YIpzU/Cv3Xg=
golang.org/x/sys v0.24.0/go.mod h1:/VUhepiaJMQUp4+oa/7Zr1D23ma6VTLIYjOOTFZPUcA=

package main

import (
	"fmt"

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

func main() {
	raw := []byte{'u', 'n', 'i', 'x', 0, 'x'}
	fmt.Println(unix.BytePtrToString(&raw[0]))
}

{
  "schemaVersion": 1,
  "goal": "verify golang.org/x/sys/unix.BytePtrToString in pkg:golang/golang.org/x/sys@v0.24.0",
  "kind": "HOW",
  "packages": [
    "pkg:golang/golang.org/x/sys@v0.24.0"
  ],
  "symbols": [
    "golang.org/x/sys/unix.BytePtrToString"
  ]
}

package main

import (
	"fmt"
	"os"

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

func main() {
	// 1. Nil pointer returns empty string
	if got := unix.BytePtrToString(nil); got != "" {
		fmt.Fprintf(os.Stderr, "expected empty string for nil pointer, got %q\n", got)
		os.Exit(1)
	}

	// 2. Pointer to immediate NUL byte returns empty string
	emptyBuf := []byte{0, 'a', 'b'}
	if got := unix.BytePtrToString(&emptyBuf[0]); got != "" {
		fmt.Fprintf(os.Stderr, "expected empty string for leading NUL byte, got %q\n", got)
		os.Exit(1)
	}

	// 3. Converts NUL-terminated ASCII/UTF-8 byte sequence and stops at first NUL
	buf := []byte{'a', 'l', 'p', 'h', 'a', 0, 'b', 'e', 't', 'a', 0}
	if got := unix.BytePtrToString(&buf[0]); got != "alpha" {
		fmt.Fprintf(os.Stderr, "expected \"alpha\", got %q\n", got)
		os.Exit(1)
	}

	// 4. Converts substring starting from an interior pointer up to its NUL terminator
	if got := unix.BytePtrToString(&buf[6]); got != "beta" {
		fmt.Fprintf(os.Stderr, "expected \"beta\", got %q\n", got)
		os.Exit(1)
	}
}