t.Error("internal.poll.SendFile called with unexpected FD")
	}
}

func TestSendfile(t *testing.T) {
	ln := newLocalListener(t, "tcp")
	defer ln.Close()

	errc := make(chan error, 1)
	go func(ln Listener) {
		// Wait for a connection.
		conn, err := ln.Accept()
		if err != nil {
			errc <- err
			close(errc)
			return
		}

		go func() {
			defer close(errc)

		t.Skipf("not supported on %s", runtime.GOOS)
	}

	ln, err := Listen("tcp", "127.0.0.1:0")
	if err != nil {
		t.Fatal(err)
	}
	defer ln.Close()
	var server Conn
	errc := make(chan error, 1)
	go func() {
		var err error
		server, err = ln.Accept()
		errc <- err
	}()
	client, err := Dial("tcp", ln.Addr().String())
	if err != nil {
		t.Fatal(err)
	}
	defer client.Close()

	case "plan9":
		t.Skipf("not supported on %s", runtime.GOOS)
	}

	ln := newLocalListener(t, "tcp")
	defer ln.Close()

	if err := ln.(*TCPListener).SetDeadline(noDeadline); err != nil {
		t.Error(err)
	}
	if err := ln.(*TCPListener).SetDeadline(time.Now().Add(10 * time.Millisecond)); err != nil {
		t.Error(err)
	}
	c, err := ln.Accept()
	if err == nil {
		c.Close()
	}

				t.Skipf("network %s is not testable on the current platform", network)
			}
			t.Parallel()

			ln := newLocalListener(t, network)
			switch network {
			case "unix", "unixpacket":
				defer os.Remove(ln.Addr().String())
			}
			defer ln.Close()

			c, err := Dial(ln.Addr().Network(), ln.Addr().String())
			if err != nil {
				t.Fatal(err)
			}
			switch network {
			case "unix", "unixpacket":

		}
	}()

	if ln, err := Listen("tcp", ""); err == nil {
		ln.Close()
	}
	if ln, err := ListenPacket("udp", ""); err == nil {
		ln.Close()
	}
	if ln, err := ListenTCP("tcp", nil); err == nil {
		ln.Close()
	}
	if ln, err := ListenUDP("udp", nil); err == nil {
		ln.Close()
	}
	if ln, err := ListenIP("ip:icmp", nil); err == nil {
		ln.Close()
	}
}

		},
		port: port,
	}, nil
}

func (ls *localServer) transponder(ln Listener, ch chan<- error) {
	defer close(ch)

	switch ln := ln.(type) {
	case *TCPListener:
		ln.SetDeadline(time.Now().Add(someTimeout))
	case *UnixListener:
		ln.SetDeadline(time.Now().Add(someTimeout))
	}
	c, err := ln.Accept()
	if err != nil {
		if perr := parseAcceptError(err); perr != nil {
			ch <- perr
		}

	})

	handler := func(ls *localServer, ln Listener) {
		for {
			c, err := ln.Accept()
			if err != nil {
				return
			}
			c.Close()
		}
	}
	ln := newLocalListener(t, "tcp", &ListenConfig{
		KeepAlive: -1, // prevent calling hook from accepting
	})
	ls := (&streamListener{Listener: ln}).newLocalServer()
	defer ls.teardown()
	if err := ls.buildup(handler); err != nil {

		}
	}
	ln.initializedChildren = true
}

// calculateDepths uses the children field of loops
// to determine the nesting depth (outer=1) of each
// loop.  This is helpful for finding exit edges.
func (ln *loopnest) calculateDepths() {
	if ln.initializedDepth {
		return
	}
	ln.assembleChildren()
	for _, l := range ln.loops {
		if l.outer == nil {
			l.setDepth(1)
		}
	}
	ln.initializedDepth = true

			t.Error(perr)
		}
	} else {
		c.Close()
		t.Error("should fail")
	}
	ln, err := FileListener(f)
	if err != nil {
		if ln != nil {
			t.Errorf("FileListener returned non-nil interface %T(%v) with err != nil", ln, ln)
		}
		if perr := parseCommonError(err); perr != nil {
			t.Error(perr)
		}
	} else {
		ln.Close()
		t.Error("should fail")
	}
	pc, err := FilePacketConn(f)
	if err != nil {

		}

		for _, name := range allNames {
			ln, ok := filter[name]
			if !ok {
				ln = listenerName{RequestedNames: sets.New[string]()}
			}
			ln.RequestedNames.Insert(requestedName)

			// only build the portmap if we aren't filtering this name yet, or if the existing filter is non-empty
			if hasPort && (!ok || len(ln.Ports) != 0) {
				if ln.Ports == nil {
					ln.Ports = map[string]struct{}{}
				}