golang.org/x/sys v0.2.0: unix.EINVAL

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.EINVAL in pkg:golang/golang.org/x/sys@v0.2.0
Kind: HOW

Use EXACTLY these public packages and versions:
  - pkg:golang/golang.org/x/sys@v0.2.0
Demonstrate these symbols/APIs:
  - golang.org/x/sys/unix.EINVAL

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:a4134e3a47c6f45f452ed58aa95e89b148e9a278c12e7389093a3f95677c7696","contract":["unix.EINVAL has the numeric value 22 matching the Linux POSIX EINVAL errno","unix.EINVAL.Error() returns \"invalid argument\"","unix.ErrnoName(unix.EINVAL) returns \"EINVAL\"","errors.Is matches unix.EINVAL against both unix.EINVAL and syscall.EINVAL while rejecting unrelated errnos","unix.EINVAL.Timeout() and unix.EINVAL.Temporary() both return false","unix.Nanosleep with a negative nanosecond field fails with an error matching unix.EINVAL"],"goal":"verify golang.org/x/sys/unix.EINVAL in pkg:golang/golang.org/x/sys@v0.2.0","kind":"HOW","packages":["pkg:golang/golang.org/x/sys@v0.2.0"],"schemaVersion":1,"symbols":["golang.org/x/sys/unix.EINVAL"]},"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@v0.2.0"],"schemaVersion":1,"subject":"pkg:golang/golang.org/x/sys@v0.2.0","symbols":["golang.org/x/sys/unix.EINVAL"],"verifierAdapter":"golang@1"}

module sample

go 1.22

require golang.org/x/sys v0.2.0

golang.org/x/sys v0.2.0 h1:ljd4t30dBnAvMZaQCevtY0xLLD0A+bRZXbgLMLU1F/A=
golang.org/x/sys v0.2.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=

{
  "schemaVersion": 1,
  "goal": "verify golang.org/x/sys/unix.EINVAL in pkg:golang/golang.org/x/sys@v0.2.0",
  "kind": "HOW",
  "packages": [
    "pkg:golang/golang.org/x/sys@v0.2.0"
  ],
  "symbols": [
    "golang.org/x/sys/unix.EINVAL"
  ]
}

package main

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

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

func fail(format string, args ...any) {
	fmt.Fprintf(os.Stderr, "FAIL: "+format+"\n", args...)
	os.Exit(1)
}

func main() {
	// 1. Numeric value of unix.EINVAL on Linux is 22.
	if int(unix.EINVAL) != 22 {
		fail("expected int(unix.EINVAL) == 22, got %d", int(unix.EINVAL))
	}

	// 2. Error() string representation is "invalid argument".
	if got := unix.EINVAL.Error(); got != "invalid argument" {
		fail("expected unix.EINVAL.Error() == %q, got %q", "invalid argument", got)
	}

	// 3. ErrnoName resolves unix.EINVAL to "EINVAL".
	if name := unix.ErrnoName(unix.EINVAL); name != "EINVAL" {
		fail("expected unix.ErrnoName(unix.EINVAL) == %q, got %q", "EINVAL", name)
	}

	// 4. errors.Is matches unix.EINVAL and syscall.EINVAL, and rejects unrelated errnos.
	var err error = unix.EINVAL
	if !errors.Is(err, unix.EINVAL) {
		fail("expected errors.Is(err, unix.EINVAL) to be true")
	}
	if !errors.Is(err, syscall.EINVAL) {
		fail("expected errors.Is(err, syscall.EINVAL) to be true")
	}
	if errors.Is(err, unix.ENOENT) {
		fail("expected errors.Is(err, unix.ENOENT) to be false")
	}

	// 5. Timeout() and Temporary() both report false for unix.EINVAL.
	if unix.EINVAL.Timeout() {
		fail("expected unix.EINVAL.Timeout() to be false")
	}
	if unix.EINVAL.Temporary() {
		fail("expected unix.EINVAL.Temporary() to be false")
	}

	// 6. Calling unix.Nanosleep with a negative Nsec field returns unix.EINVAL.
	req := unix.Timespec{Sec: 0, Nsec: -1}
	callErr := unix.Nanosleep(&req, nil)
	if callErr == nil {
		fail("expected unix.Nanosleep with negative Nsec to fail")
	}
	if !errors.Is(callErr, unix.EINVAL) {
		fail("expected unix.Nanosleep error %v to match unix.EINVAL", callErr)
	}

	fmt.Println("PASS")
}