anchor.diff:           connect_rsa_to_ecdsa/1,
            connect_rsa_to_ed25519/1,
            connect_rsa_to_ed448/1,
  -         connect_rsa_to_rsa/1
  +         connect_rsa_to_rsa/1,
  +
  +         chk_known_hosts/1
           ]).
   
   -include_lib("common_test/include/ct.hrl").
  
positive.code: all() -> 
      [{group, old_format},
       {group, new_format},
       {group, option_space}
      ].
  
  
  
negative.code: 
  
  %%%----------------------------------------------------------------
  chk_known_hosts(Config) ->
      PrivDir = proplists:get_value(priv_dir, Config),
  
      DataDir = filename:join(proplists:get_value(data_dir,Config), "new_format"),
      SysDir = filename:join(PrivDir, "chk_known_hosts_sys_dir"),
      ssh_test_lib:setup_all_host_keys(DataDir, SysDir),
  
      UsrDir = filename:join(PrivDir, "chk_known_hosts_usr_dir"),
      file:make_dir(UsrDir),
      KnownHostsFile = filename:join(UsrDir, "known_hosts"),
  
      DaemonOpts = [{system_dir, SysDir},
                    {user_dir, UsrDir},
                    {password, "bar"}],
  
      UserOpts = [{user_dir, UsrDir},
                  {user, "foo"},
                  {password, "bar"},
                  {silently_accept_hosts, true},
                  {user_interaction, false}
                 ],
  
      {_Pid1, Host1, Port1} = ssh_test_lib:daemon(DaemonOpts),
      {_Pid2, Host2, Port2} = ssh_test_lib:daemon(DaemonOpts),
  
      _C1 = ssh_test_lib:connect(Host1, Port1, UserOpts),
      {ok,KnownHosts1} = file:read_file(KnownHostsFile),
      Sz1 = byte_size(KnownHosts1),
      ct:log("~p bytes KnownHosts1 = ~p", [Sz1, KnownHosts1]),
  
      _C2 = ssh_test_lib:connect(Host2, Port2, UserOpts),
      {ok,KnownHosts2} = file:read_file(KnownHostsFile),
      Sz2 = byte_size(KnownHosts2),
      ct:log("~p bytes KnownHosts2 = ~p", [Sz2, KnownHosts2]),
  
      %% Check that 2nd is appended after the 1st:
      <<KnownHosts1:Sz1/binary, _/binary>> = KnownHosts2,
  
      %% Check that there are exactly two NLs:
      2 = lists:foldl(fun($\n, Sum) -> Sum + 1;
                         (_,   Sum) -> Sum
                      end, 0, binary_to_list(KnownHosts2)),
  
      %% Check that at least one NL terminates both two lines:
      <<_:(Sz1-1)/binary, $\n, _:(Sz2-Sz1-1)/binary, $\n>> = KnownHosts2.
  
  
  %%%----------------------------------------------------------------
  try_connect({skip,Reson}) ->
      {skip,Reson};
  try_connect(Config) ->
  