}
	return c.fd.writeTo(b, sa)
}

func (c *IPConn) writeMsg(b, oob []byte, addr *IPAddr) (n, oobn int, err error) {
	if c.fd.isConnected {
		return 0, 0, ErrWriteToConnected
	}
	if addr == nil {
		return 0, 0, errMissingAddress
	}
	sa, err := addr.sockaddr(c.fd.family)
	if err != nil {
		return 0, 0, err
	}
	return c.fd.writeMsg(b, oob, sa)
}

			answer.Rcode = dns.RcodeSuccess
			if err := resp.WriteMsg(&answer); err != nil {
				t.Fatalf("err: %s", err)
			}
		})
	}
	mux.HandleFunc("giant.", func(resp dns.ResponseWriter, msg *dns.Msg) {
		answer := &dns.Msg{
			Answer: giantResponse,
		}
		answer.SetReply(msg)
		answer.Rcode = dns.RcodeSuccess
		if err := resp.WriteMsg(answer); err != nil {
			t.Fatalf("err: %s", err)
		}
	})

	}
	if addr.Net != sotypeToNet(c.fd.sotype) {
		return 0, syscall.EAFNOSUPPORT
	}
	sa := &syscall.SockaddrUnix{Name: addr.Name}
	return c.fd.writeTo(b, sa)
}

func (c *UnixConn) writeMsg(b, oob []byte, addr *UnixAddr) (n, oobn int, err error) {
	if c.fd.sotype == syscall.SOCK_DGRAM && c.fd.isConnected {
		return 0, 0, ErrWriteToConnected
	}
	var sa syscall.Sockaddr
	if addr != nil {

			if err = fd.pd.waitWrite(fd.isFile); err == nil {
				continue
			}
		}
		if err != nil {
			return 0, err
		}
		return len(p), nil
	}
}

// WriteMsg wraps the sendmsg network call.
func (fd *FD) WriteMsg(p []byte, oob []byte, sa syscall.Sockaddr) (int, int, error) {
	if err := fd.writeLock(); err != nil {
		return 0, 0, err
	}
	defer fd.writeUnlock()

	}
}

func (c *UDPConn) writeMsg(b, oob []byte, addr *UDPAddr) (n, oobn int, err error) {
	if c.fd.isConnected && addr != nil {
		return 0, 0, ErrWriteToConnected
	}
	if !c.fd.isConnected && addr == nil {
		return 0, 0, errMissingAddress
	}
	sa, err := addr.sockaddr(c.fd.family)
	if err != nil {
		return 0, 0, err
	}
	return c.fd.writeMsg(b, oob, sa)
}

			return false
		}
	}

	return true
}

func condFatalf(t *testing.T, network string, format string, args ...any) {
	t.Helper()
	// A few APIs like File and Read/WriteMsg{UDP,IP} are not
	// fully implemented yet on Plan 9 and Windows.
	switch runtime.GOOS {
	case "windows", "js", "wasip1":
		if network == "file+net" {
			t.Logf(format, args...)
			return
		}

	}
	n, err = ffd.readFromInet6(p, sa)
	return n, 0, 0, err
}

func (ffd *fakeNetFD) writeMsg(p []byte, oob []byte, sa syscall.Sockaddr) (n int, oobn int, err error) {
	if len(oob) > 0 {
		return 0, 0, os.NewSyscallError("writeMsg", syscall.ENOTSUP)
	}
	n, err = ffd.writeTo(p, sa)
	return n, 0, err
}

		response.SetReply(req)
		response.Rcode = dns.RcodeServerFailure
		_ = w.WriteMsg(response)
		return
	}

	lp := h.lookupTable.Load()
	hostname := strings.ToLower(req.Question[0].Name)
	if lp == nil {
		if h.respondBeforeSync {
			response = h.upstream(proxy, req, hostname)
			response.Truncate(size(proxy.protocol, req))
			_ = w.WriteMsg(response)
		} else {

			case dns.TypeANY:
				msg.Rcode = dns.RcodeRefused
			default:
				msg.Rcode = dns.RcodeNotImplemented
			}
		} else {
			msg.Rcode = dns.RcodeNameError
		}
	}
	if err := w.WriteMsg(msg); err != nil {
		scopes.Framework.Errorf("failed writing fake DNS response: %v", err)
	}
}

func (s *fakeDNSServer) setHosts(hosts sets.String) {
	s.mu.Lock()
	defer s.mu.Unlock()

// used to manipulate IP-level socket options in oob.
func (c *IPConn) WriteMsgIP(b, oob []byte, addr *IPAddr) (n, oobn int, err error) {
	if !c.ok() {
		return 0, 0, syscall.EINVAL
	}
	n, oobn, err = c.writeMsg(b, oob, addr)
	if err != nil {
		err = &OpError{Op: "write", Net: c.fd.net, Source: c.fd.laddr, Addr: addr.opAddr(), Err: err}
	}
	return
}

func newIPConn(fd *netFD) *IPConn { return &IPConn{conn{fd}} }