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

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.EBADF 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.EBADF

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:sha256:3918d9c2badeea5d0085169e66dbc1180e12cb31e06d2c1306d2125c1bc473dc","contract":["unix.EBADF represents errno 9 with error string \"bad file descriptor\"","unix.Close with negative file descriptor returns unix.EBADF","unix.Read with invalid file descriptor fails with unix.EBADF","unix.Fstat with invalid file descriptor fails with unix.EBADF","errors.Is matches unix.EBADF with syscall.EBADF","unix.EBADF reports false for Temporary and Timeout errors"],"goal":"verify golang.org/x/sys/unix.EBADF 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.EBADF"]},"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.EBADF"],"verifierAdapter":"golang@1"}

module sample

go 1.24.0

require golang.org/x/sys v0.41.0

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

{
  "schemaVersion": 1,
  "goal": "verify golang.org/x/sys/unix.EBADF 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.EBADF"
  ]
}

package main

import (
	"errors"
	"fmt"
	"os"
	"syscall"

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

func main() {
	if err := runTests(); err != nil {
		fmt.Fprintf(os.Stderr, "Contract test failed: %v\n", err)
		os.Exit(1)
	}
	fmt.Println("All contract tests passed successfully.")
}

func runTests() error {
	// 1. unix.EBADF represents errno 9 with error string "bad file descriptor"
	if uintptr(unix.EBADF) != 9 {
		return fmt.Errorf("expected unix.EBADF to be 9, got %d", uintptr(unix.EBADF))
	}
	if unix.EBADF.Error() != "bad file descriptor" {
		return fmt.Errorf("expected error string 'bad file descriptor', got %q", unix.EBADF.Error())
	}

	// 2. unix.Close with negative file descriptor returns unix.EBADF
	closeErr := unix.Close(-1)
	if closeErr == nil {
		return fmt.Errorf("expected unix.Close(-1) to fail, got nil")
	}
	if !errors.Is(closeErr, unix.EBADF) {
		return fmt.Errorf("expected unix.Close(-1) error to be unix.EBADF, got %v", closeErr)
	}

	// 3. unix.Read with invalid file descriptor fails with unix.EBADF
	buf := make([]byte, 16)
	_, readErr := unix.Read(-1, buf)
	if readErr == nil {
		return fmt.Errorf("expected unix.Read(-1) to fail, got nil")
	}
	if !errors.Is(readErr, unix.EBADF) {
		return fmt.Errorf("expected unix.Read(-1) error to be unix.EBADF, got %v", readErr)
	}

	// 4. unix.Fstat with invalid file descriptor fails with unix.EBADF
	var stat unix.Stat_t
	fstatErr := unix.Fstat(-1, &stat)
	if fstatErr == nil {
		return fmt.Errorf("expected unix.Fstat(-1) to fail, got nil")
	}
	if !errors.Is(fstatErr, unix.EBADF) {
		return fmt.Errorf("expected unix.Fstat(-1) error to be unix.EBADF, got %v", fstatErr)
	}

	// 5. errors.Is matches unix.EBADF with syscall.EBADF
	if !errors.Is(unix.EBADF, syscall.EBADF) {
		return fmt.Errorf("expected errors.Is(unix.EBADF, syscall.EBADF) to be true")
	}
	if !errors.Is(syscall.EBADF, unix.EBADF) {
		return fmt.Errorf("expected errors.Is(syscall.EBADF, unix.EBADF) to be true")
	}

	// 6. unix.EBADF reports false for Temporary and Timeout errors
	if unix.EBADF.Temporary() {
		return fmt.Errorf("expected unix.EBADF.Temporary() to be false")
	}
	if unix.EBADF.Timeout() {
		return fmt.Errorf("expected unix.EBADF.Timeout() to be false")
	}

	return nil
}