poll.CloseFunc(s)
		return -1, os.NewSyscallError("setnonblock", err)
	}
	return s, nil
}

func newFileFD(f *os.File) (*netFD, error) {
	s, err := dupSocket(f)
	if err != nil {
		return nil, err
	}
	family := syscall.AF_UNSPEC
	sotype, err := syscall.GetsockoptInt(s, syscall.SOL_SOCKET, syscall.SO_TYPE)
	if err != nil {
		poll.CloseFunc(s)

	// Placeholders for saving original socket system calls.
	origWSASocket   = wsaSocketFunc
	origClosesocket = poll.CloseFunc
	origConnect     = connectFunc
	origConnectEx   = poll.ConnectExFunc
	origListen      = listenFunc
	origAccept      = poll.AcceptFunc
)

func installTestHooks() {
	wsaSocketFunc = sw.WSASocket
	poll.CloseFunc = sw.Closesocket
	connectFunc = sw.Connect
	poll.ConnectExFunc = sw.ConnectEx
	listenFunc = sw.Listen

	"sync/atomic"
	"testing"
	"time"
)

var closeHook atomic.Value // func(fd int)

func init() {
	closeFunc := poll.CloseFunc
	poll.CloseFunc = func(fd int) (err error) {
		if v := closeHook.Load(); v != nil {
			if hook := v.(func(int)); hook != nil {
				hook(fd)
			}
		}
		return closeFunc(fd)
	}
}

func TestSplicePipePool(t *testing.T) {
	const N = 64
	var (
		p          *poll.SplicePipe

	"os"
	"sync"
	"syscall"
	"testing"
)

var sw socktest.Switch

func TestMain(m *testing.M) {
	installTestHooks()

	st := m.Run()

	for s := range sw.Sockets() {
		closeFunc(s)
	}
	uninstallTestHooks()
	os.Exit(st)
}

func TestSwitch(t *testing.T) {
	const N = 10
	var wg sync.WaitGroup
	wg.Add(N)
	for i := 0; i < N; i++ {
		go func() {
			defer wg.Done()

	if err == nil {
		syscall.CloseOnExec(s)
	}
	syscall.ForkLock.RUnlock()
	if err != nil {
		return -1, os.NewSyscallError("socket", err)
	}
	if err = syscall.SetNonblock(s, true); err != nil {
		poll.CloseFunc(s)
		return -1, os.NewSyscallError("setnonblock", err)
	}
	return s, nil

	ns, sa, err := AcceptFunc(s)
	if err == nil {
		syscall.CloseOnExec(ns)
	}
	if err != nil {
		return -1, nil, "accept", err
	}
	if err = syscall.SetNonblock(ns, true); err != nil {
		CloseFunc(ns)
		return -1, nil, "setnonblock", err
	}
	return ns, sa, "", nil

	s, err := sysSocket(family, sotype, proto)
	if err != nil {
		return nil, err
	}
	if err = setDefaultSockopts(s, family, sotype, ipv6only); err != nil {
		poll.CloseFunc(s)
		return nil, err
	}
	if fd, err = newFD(s, family, sotype, net); err != nil {
		poll.CloseFunc(s)
		return nil, err
	}

	// This function makes a network file descriptor for the
	// following applications:
	//

		c.forget(graceful)
	}

	if timer == nil {
		closeFunc()
		return false
	}

	// OK, block sending, but only until timer fires.
	select {
	case c.input <- event:
		return true
	case <-timer.C:
		closeFunc()
		return false
	}
}

	return &splicePipe{splicePipeFields: splicePipeFields{rfd: fds[0], wfd: fds[1]}}
}

// destroyPipe destroys a pipe.
func destroyPipe(p *splicePipe) {
	CloseFunc(p.rfd)
	CloseFunc(p.wfd)

		p.ipv4MappedIPv6Enabled = true
		return
	}

	s, err := sysSocket(syscall.AF_INET, syscall.SOCK_STREAM, syscall.IPPROTO_TCP)
	switch err {
	case syscall.EAFNOSUPPORT, syscall.EPROTONOSUPPORT:
	case nil:
		poll.CloseFunc(s)
		p.ipv4Enabled = true
	}
	var probes = []struct {
		laddr TCPAddr
		value int
	}{
		// IPv6 communication capability
		{laddr: TCPAddr{IP: ParseIP("::1")}, value: 1},