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
	poll.AcceptFunc = sw.AcceptEx
}

func uninstallTestHooks() {
	wsaSocketFunc = origWSASocket

	// because we have put fd.sysfd into non-blocking mode.
	// However, a call to the File method will put it back into
	// blocking mode. We can't take that risk, so no use of ForkLock here.
	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

	// Submit accept request.
	o.handle = s
	o.rsan = int32(unsafe.Sizeof(rawsa[0]))
	_, err := execIO(o, func(o *operation) error {
		return AcceptFunc(o.fd.Sysfd, o.handle, (*byte)(unsafe.Pointer(&rawsa[0])), 0, uint32(o.rsan), uint32(o.rsan), &o.qty, &o.o)
	})
	if err != nil {
		CloseFunc(s)
		return "acceptex", err
	}