}
	p.Wait()

	// Use pid of a non-existing process.
	proc, err := os.FindProcess(p.Pid)
	// FindProcess should never return errors on Unix.
	if err != nil {
		t.Fatalf("FindProcess: got error %v, want <nil>", err)
	}
	// FindProcess should never return nil Process.
	if proc == nil {
		t.Fatal("FindProcess: got nil, want non-nil")
	}
	if proc.Status() != os.StatusDone {

		// EINVAL (see waitid in usr/src/uts/common/os/exit.c in
		// illumos). This is configurable via sysconf(_SC_MAXPID), but
		// we'll just take the default.
		pid = 30000-1
	}

	p, err := FindProcess(pid)
	if err != nil {
		t.Fatalf("FindProcess(math.MaxInt32) got err %v, want nil", err)
	}

	if ps, err := p.Wait(); !errors.Is(err, syscall.ECHILD) {
		t.Errorf("Wait() got err %v (ps %+v), want %v", err, ps, syscall.ECHILD)
	}

// it should abandon its work after a signal is received.
func ExampleNotifyContext() {
	ctx, stop := signal.NotifyContext(context.Background(), os.Interrupt)
	defer stop()

	p, err := os.FindProcess(os.Getpid())
	if err != nil {
		log.Fatal(err)
	}

	// On a Unix-like system, pressing Ctrl+C on a keyboard sends a
	// SIGINT signal to the process of the program in execution.
	//

	"os"
	"os/signal"
	"runtime"
	"syscall"
	"testing"
	"time"
)

func TestProcessLiteral(t *testing.T) {
	if runtime.GOOS == "windows" {
		t.Skip("Process literals do not work on Windows. FindProcess/etc must initialize the process handle")
	}
	if runtime.GOARCH == "wasm" {
		t.Skip("Signals send + notify not fully supported om wasm port")
	}

	c := make(chan os.Signal, 1)
	signal.Notify(c, os.Interrupt)

			// to the main test process and its parent.
			for _, pid := range strings.Split(pids, ",") {
				i, err := strconv.Atoi(pid)
				if err != nil {
					t.Fatal(err)
				}
				if p, err := os.FindProcess(i); err == nil {
					p.Signal(os.Interrupt)
					sentInterrupt = true // Only send interrupts once.
				}
			}
		}
		time.Sleep(1 * time.Millisecond)  // Delay the fuzzer a bit to avoid wasting CPU.
	})

	p.Pid = -1

	// Just mark the PID unusable.
	p.pidDeactivate(statusReleased)

	// no need for a finalizer anymore
	runtime.SetFinalizer(p, nil)
	return nil
}

func findProcess(pid int) (p *Process, err error) {
	// NOOP for Plan 9.
	return newPIDProcess(pid), nil
}

// ProcessState stores information about a process, as reported by Wait.
type ProcessState struct {

	case modePID:
		// Just mark the PID unusable.
		p.pidDeactivate(statusReleased)
	}
	// no need for a finalizer anymore
	runtime.SetFinalizer(p, nil)
	return nil
}

func findProcess(pid int) (p *Process, err error) {
	h, err := pidfdFind(pid)
	if err == ErrProcessDone {
		// We can't return an error here since users are not expecting
		// it. Instead, return a process with a "done" state already

	}

	// no need for a finalizer anymore
	runtime.SetFinalizer(p, nil)
	return nil
}

func (p *Process) closeHandle() {
	syscall.CloseHandle(syscall.Handle(p.handle))
}

func findProcess(pid int) (p *Process, err error) {
	const da = syscall.STANDARD_RIGHTS_READ |
		syscall.PROCESS_QUERY_INFORMATION | syscall.SYNCHRONIZE
	h, e := syscall.OpenProcess(da, false, uint32(pid))
	if e != nil {

CL 570681 ("os: make FindProcess use pidfd on Linux") mentions accepted proposal go.dev/issue/51246 (described as fully implemented in Go 1.22) and NeedsInvestigation continuation issue go.dev/issue/62654.