Merge branch 'bmk/201818/nififying_inet_move_test_kernel_to_emu/OTP-14831' into bmk/20180918/nififying_inet/OTP-14831

1 files changed, 4281 insertions, 0 deletions

diff --git a/erts/emulator/test/socket_SUITE.erl b/erts/emulator/test/socket_SUITE.erl
new file mode 100644
index 0000000000..92dd5e7097
--- /dev/null
+++ b/erts/emulator/test/socket_SUITE.erl
@@ -0,0 +1,4281 @@
+%%
+%% %CopyrightBegin%
+%% 
+%% Copyright Ericsson AB 2018-2018. All Rights Reserved.
+%% 
+%% Licensed under the Apache License, Version 2.0 (the "License");
+%% you may not use this file except in compliance with the License.
+%% You may obtain a copy of the License at
+%%
+%%     http://www.apache.org/licenses/LICENSE-2.0
+%%
+%% Unless required by applicable law or agreed to in writing, software
+%% distributed under the License is distributed on an "AS IS" BASIS,
+%% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+%% See the License for the specific language governing permissions and
+%% limitations under the License.
+%% 
+%% %CopyrightEnd%
+%%
+
+-module(socket_SUITE).
+
+-include_lib("common_test/include/ct.hrl").
+-include_lib("common_test/include/ct_event.hrl").
+
+%% Suite exports
+-export([suite/0, all/0, groups/0]).
+-export([init_per_suite/1,    end_per_suite/1,
+         init_per_testcase/2, end_per_testcase/2]).
+
+%% Test cases
+-export([
+         %% API Basic
+         api_b_open_and_close_udp4/1,
+         api_b_open_and_close_tcp4/1,
+         api_b_sendto_and_recvfrom_udp4/1,
+         api_b_sendmsg_and_recvmsg_udp4/1,
+         api_b_send_and_recv_tcp4/1,
+         api_b_sendmsg_and_recvmsg_tcp4/1,
+
+         %% API Options
+         api_opt_simple_otp_options/1,
+         api_opt_simple_otp_controlling_process/1,
+
+         %% API Operation Timeout
+         api_to_connect_tcp4/1,
+         api_to_connect_tcp6/1,
+         api_to_accept_tcp4/1,
+         api_to_accept_tcp6/1,
+         api_to_maccept_tcp4/1,
+         api_to_maccept_tcp6/1,
+         api_to_send_tcp4/1,
+         api_to_send_tcp6/1,
+         api_to_sendto_udp4/1,
+         api_to_sendto_udp6/1,
+         api_to_sendmsg_tcp4/1,
+         api_to_sendmsg_tcp6/1,
+         api_to_recv_udp4/1,
+         api_to_recv_udp6/1,
+         api_to_recv_tcp4/1,
+         api_to_recv_tcp6/1,
+         api_to_recvfrom_udp4/1,
+         api_to_recvfrom_udp6/1,
+         api_to_recvmsg_udp4/1,
+         api_to_recvmsg_udp6/1,
+         api_to_recvmsg_tcp4/1,
+         api_to_recvmsg_tcp6/1,
+
+         %% Socket Closure
+         sc_cpe_socket_cleanup_tcp4/1,
+         sc_cpe_socket_cleanup_tcp6/1,
+         sc_cpe_socket_cleanup_udp4/1,
+         sc_cpe_socket_cleanup_udp6/1,
+         sc_lc_recv_response_tcp4/1,
+         sc_lc_recv_response_tcp6/1,
+         sc_lc_recvmsg_response_tcp4/1,
+         sc_lc_recvmsg_response_tcp6/1,
+         sc_lc_acceptor_response_tcp4/1,
+         sc_lc_acceptor_response_tcp6/1,
+         sc_rc_recv_response_tcp4/1,
+         sc_rc_recv_response_tcp6/1,
+         sc_rc_recvmsg_response_tcp4/1,
+         sc_rc_recvmsg_response_tcp6/1
+
+         %% Tickets
+        ]).
+
+%% Internal exports
+%% -export([]).
+
+-record(ev, {name :: string(),
+             pid  :: pid(),
+             mref :: reference()}).
+-type ev() :: #ev{}.
+-define(MKEV(N,P,R), #ev{name = N, pid = P, mref = R}).
+-type initial_evaluator_state() :: map().
+-type evaluator_state() :: term().
+-type command_fun() :: 
+        fun((State :: evaluator_state()) -> ok) |
+        fun((State :: evaluator_state()) -> {ok, evaluator_state()}) |
+        fun((State :: evaluator_state()) -> {error, term()}).
+
+-type command() :: #{desc  := string(),
+                     cmd   := command_fun()}.
+
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+-define(BASIC_REQ, <<"hejsan">>).
+-define(BASIC_REP, <<"hoppsan">>).
+
+-define(FAIL(R), exit(R)).
+
+-define(SLEEP(T), receive after T -> ok end).
+
+-define(MINS(M), timer:minutes(M)).
+-define(SECS(S), timer:seconds(S)).
+
+-define(TT(T),   ct:timetrap(T)).
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+suite() ->
+    [{ct_hooks,[ts_install_cth]},
+     {timetrap,{minutes,1}}].
+
+all() -> 
+    [
+     {group, api},
+     {group, socket_closure}
+     %% {group, tickets}
+    ].
+
+groups() -> 
+    [{api,                 [], api_cases()},
+     {api_basic,           [], api_basic_cases()},
+     {api_options,         [], api_options_cases()},
+     {api_op_with_timeout, [], api_op_with_timeout_cases()},
+     {socket_closure,      [], socket_closure_cases()},
+     {sc_ctrl_proc_exit,   [], sc_cp_exit_cases()},
+     {sc_local_close,      [], sc_lc_cases()},
+     {sc_remote_close,     [], sc_rc_cases()}
+     %% {tickets,             [], ticket_cases()}
+    ].
+     
+api_cases() ->
+    [
+     {group, api_basic},
+     {group, api_options},
+     {group, api_op_with_timeout}
+    ].
+
+api_basic_cases() ->
+    [
+     api_b_open_and_close_udp4,
+     api_b_open_and_close_tcp4,
+     api_b_sendto_and_recvfrom_udp4,
+     api_b_sendmsg_and_recvmsg_udp4,
+     api_b_send_and_recv_tcp4,
+     api_b_sendmsg_and_recvmsg_tcp4
+    ].
+
+api_options_cases() ->
+    [
+     api_opt_simple_otp_options,
+     api_opt_simple_otp_controlling_process
+    ].
+
+api_op_with_timeout_cases() ->
+    [
+     api_to_connect_tcp4,
+     api_to_connect_tcp6,
+     api_to_accept_tcp4,
+     api_to_accept_tcp6,
+     api_to_maccept_tcp4,
+     api_to_maccept_tcp6,
+     api_to_send_tcp4,
+     api_to_send_tcp6,
+     api_to_sendto_udp4,
+     api_to_sendto_udp6,
+     api_to_sendmsg_tcp4,
+     api_to_sendmsg_tcp6,
+     api_to_recv_udp4,
+     api_to_recv_udp6,
+     api_to_recv_tcp4,
+     api_to_recv_tcp6,
+     api_to_recvfrom_udp4,
+     api_to_recvfrom_udp6,
+     api_to_recvmsg_udp4,
+     api_to_recvmsg_udp6,
+     api_to_recvmsg_tcp4,
+     api_to_recvmsg_tcp6
+    ].
+
+%% These cases tests what happens when the socket is closed, locally or
+%% remotely.
+socket_closure_cases() ->
+    [
+     {group, sc_ctrl_proc_exit},
+     {group, sc_local_close},
+     {group, sc_remote_close}
+    ].
+
+%% These cases are all about socket cleanup after the controlling process
+%% exits *without* calling socket:close/1.
+sc_cp_exit_cases() ->
+    [
+     sc_cpe_socket_cleanup_tcp4,
+     sc_cpe_socket_cleanup_tcp6,
+     sc_cpe_socket_cleanup_udp4,
+     sc_cpe_socket_cleanup_udp6
+    ].
+
+%% These cases tests what happens when the socket is closed locally.
+sc_lc_cases() ->
+    [
+     sc_lc_recv_response_tcp4,
+     sc_lc_recv_response_tcp6,
+
+     sc_lc_recvmsg_response_tcp4,
+     sc_lc_recvmsg_response_tcp6,
+
+     sc_lc_acceptor_response_tcp4,
+     sc_lc_acceptor_response_tcp6
+    ].
+
+%% These cases tests what happens when the socket is closed remotely.
+sc_rc_cases() ->
+    [
+     sc_rc_recv_response_tcp4,
+     sc_rc_recv_response_tcp6,
+
+     sc_rc_recvmsg_response_tcp4,
+     sc_rc_recvmsg_response_tcp6
+    ].
+
+
+%% ticket_cases() ->
+%%     [].
+
+
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+init_per_suite(Config) ->
+    Config.
+
+end_per_suite(_) ->
+    ok.
+
+init_per_testcase(_TC, Config) ->
+    Config.
+
+end_per_testcase(_TC, Config) ->
+    Config.
+
+
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%%                                                                     %%
+%%                           API BASIC                                 %%
+%%                                                                     %%
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+%% Basically open (create) and close an IPv4 UDP (dgram) socket.
+%% With some extra checks...
+api_b_open_and_close_udp4(suite) ->
+    [];
+api_b_open_and_close_udp4(doc) ->
+    [];
+api_b_open_and_close_udp4(_Config) when is_list(_Config) ->
+    ?TT(?SECS(5)),
+    tc_try(api_b_open_and_close_udp4,
+           fun() ->
+                   InitState = #{domain   => inet,
+                                 type     => dgram,
+                                 protocol => udp},
+                   ok = api_b_open_and_close(InitState)
+           end).
+
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+%% Basically open (create) and close an IPv4 TCP (stream) socket.
+%% With some extra checks...
+api_b_open_and_close_tcp4(suite) ->
+    [];
+api_b_open_and_close_tcp4(doc) ->
+    [];
+api_b_open_and_close_tcp4(_Config) when is_list(_Config) ->
+    ?TT(?SECS(5)),
+    tc_try(api_b_open_and_close_tcp4,
+           fun() ->
+                   InitState = #{domain   => inet,
+                                 type     => stream,
+                                 protocol => tcp},
+                   ok = api_b_open_and_close(InitState)
+           end).
+
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+api_b_open_and_close(InitState) ->
+    Seq = 
+        [
+         #{desc => "open",
+           cmd  => fun(#{domain   := Domain,
+                         type     := Type,
+                         protocol := Protocol} = S) -> 
+                           Res = socket:open(Domain, Type, Protocol), 
+                           {ok, {S, Res}} 
+                   end},
+         #{desc => "validate open",
+           cmd  => fun({S, {ok, Sock}}) -> 
+                           NewS = S#{socket => Sock},
+                           {ok, NewS};
+                      ({_, {error, _} = ERROR}) ->
+                           ERROR
+                   end},
+         #{desc => "get domain (maybe)",
+           cmd  => fun(#{socket := Sock} = S) ->
+                           Res = socket:getopt(Sock, socket, domain),
+                           {ok, {S, Res}}
+                   end},
+         #{desc => "validate domain (maybe)",
+           cmd  => fun({#{domain := Domain} = S, {ok, Domain}}) -> 
+                           {ok, S};
+                      ({#{domain := ExpDomain}, {ok, Domain}}) ->
+                           {error, {unexpected_domain, ExpDomain, Domain}};
+                      %% Some platforms do not support this option
+                      ({S, {error, einval}}) ->
+                           {ok, S};
+                      ({_, {error, _} = ERROR}) ->
+                           ERROR
+                   end},
+         #{desc => "get type",
+           cmd  => fun(#{socket := Sock} = State) ->
+                           Res = socket:getopt(Sock, socket, type), 
+                           {ok, {State, Res}}
+                   end},
+         #{desc => "validate type",
+           cmd  => fun({#{type := Type} = State, {ok, Type}}) ->
+                           {ok, State};
+                      ({#{type := ExpType}, {ok, Type}}) ->
+                           {error, {unexpected_type, ExpType, Type}};
+                      ({_, {error, _} = ERROR}) ->
+                           ERROR
+                   end},
+         #{desc => "get protocol",
+           cmd  => fun(#{socket := Sock} = State) ->
+                           Res = socket:getopt(Sock, socket, protocol),
+                           {ok, {State, Res}}
+                   end},
+         #{desc => "validate protocol",
+           cmd  => fun({#{protocol := Protocol} = State, {ok, Protocol}}) ->
+                           {ok, State};
+                      ({#{protocol := ExpProtocol}, {ok, Protocol}}) ->
+                           {error, {unexpected_type, ExpProtocol, Protocol}};
+                      ({_, {error, _} = ERROR}) ->
+                           ERROR
+                   end},
+         #{desc => "get controlling-process",
+           cmd  => fun(#{socket := Sock} = State) ->
+                           Res = socket:getopt(Sock, otp, controlling_process),
+                           {ok, {State, Res}}
+                   end},
+         #{desc => "validate controlling-process",
+           cmd  => fun({State, {ok, Pid}}) ->
+                           case self() of
+                               Pid ->
+                                   {ok, State};
+                               _ ->
+                                   {error, {unexpected_owner, Pid}}
+                           end;
+                      ({_, {error, _} = ERROR}) ->
+                           ERROR
+                   end},
+         #{desc => "close socket",
+           cmd  => fun(#{socket := Sock} = State) ->
+                           Res = socket:close(Sock),
+                           {ok, {State, Res}}
+                   end},
+         #{desc => "validate socket close",
+           cmd  => fun({_, ok}) ->
+                           {ok, normal};
+                      ({_, {error, _} = ERROR}) ->
+                           ERROR
+                   end}],
+    Evaluator = evaluator_start("tester", Seq, InitState),
+    ok = await_evaluator_finish([Evaluator]).
+
+
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+%% Basically send and receive on an IPv4 UDP (dgram) socket using
+%% sendto and recvfrom..
+api_b_sendto_and_recvfrom_udp4(suite) ->
+    [];
+api_b_sendto_and_recvfrom_udp4(doc) ->
+    [];
+api_b_sendto_and_recvfrom_udp4(_Config) when is_list(_Config) ->
+    ?TT(?SECS(5)),
+    tc_try(api_b_sendto_and_recvfrom_udp4,
+           fun() ->
+                   Send = fun(Sock, Data, Dest) ->
+                                  socket:sendto(Sock, Data, Dest)
+                          end,
+                   Recv = fun(Sock) ->
+                                  socket:recvfrom(Sock)
+                          end,
+                   InitState = #{domain => inet,
+                                 send   => Send,
+                                 recv   => Recv},
+                   ok = api_b_send_and_recv_udp(InitState)
+           end).
+
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+%% Basically send and receive on an IPv4 UDP (dgram) socket
+%% using sendmsg and recvmsg.
+api_b_sendmsg_and_recvmsg_udp4(suite) ->
+    [];
+api_b_sendmsg_and_recvmsg_udp4(doc) ->
+    [];
+api_b_sendmsg_and_recvmsg_udp4(_Config) when is_list(_Config) ->
+    ?TT(?SECS(5)),
+    tc_try(api_b_sendmsg_and_recvmsg_udp4,
+           fun() ->
+                   Send = fun(Sock, Data, Dest) ->
+                                  %% CMsgHdr  = #{level => ip,
+                                  %%              type  => tos,
+                                  %%              data  => reliability},
+                                  %% CMsgHdrs = [CMsgHdr],
+                   MsgHdr = #{addr => Dest,
+                              %% ctrl => CMsgHdrs,
+                              iov  => [Data]},
+                                  socket:sendmsg(Sock, MsgHdr)
+                          end,
+                   Recv = fun(Sock) ->
+                                  case socket:recvmsg(Sock) of
+                                      {ok, #{addr  := Source,
+                                             iov   := [Data]}} ->
+                                          {ok, {Source, Data}};
+                                      {error, _} = ERROR ->
+                                          ERROR
+                                  end
+                          end,
+                   InitState = #{domain => inet,
+                                 send   => Send,
+                                 recv   => Recv},
+                   ok = api_b_send_and_recv_udp(InitState)
+           end).
+
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+api_b_send_and_recv_udp(InitState) ->
+    Seq = 
+        [
+         #{desc => "local address",
+           cmd  => fun(#{domain := Domain} = State) ->
+                           LAddr = which_local_addr(Domain),
+                           LSA   = #{family => Domain, addr => LAddr},
+                           {ok, State#{lsa => LSA}}
+                   end},
+         #{desc => "open src socket",
+           cmd  => fun(#{domain := Domain} = State) ->
+                           Sock = sock_open(Domain, dgram, udp),
+                           SASrc = sock_sockname(Sock),
+                           {ok, State#{sock_src => Sock, sa_src => SASrc}}
+                   end},
+         #{desc => "bind src",
+           cmd  => fun(#{sock_src := Sock, lsa := LSA}) ->
+                           sock_bind(Sock, LSA),
+                           ok
+                   end},
+         #{desc => "sockname src socket",
+           cmd  => fun(#{sock_src := Sock} = State) ->
+                           SASrc = sock_sockname(Sock),
+                           %% ei("src sockaddr: ~p", [SASrc]),
+                           {ok, State#{sa_src => SASrc}}
+                   end},
+         #{desc => "open dst socket",
+           cmd  => fun(#{domain := Domain} = State) ->
+                           Sock = sock_open(Domain, dgram, udp),
+                           {ok, State#{sock_dst => Sock}}
+                   end},
+         #{desc => "bind dst",
+           cmd  => fun(#{sock_dst := Sock, lsa := LSA}) ->
+                           sock_bind(Sock, LSA),
+                           ok
+                   end},
+         #{desc => "sockname dst socket",
+           cmd  => fun(#{sock_dst := Sock} = State) ->
+                           SADst = sock_sockname(Sock),
+                           %% ei("dst sockaddr: ~p", [SADst]),
+                           {ok, State#{sa_dst => SADst}}
+                   end},
+         #{desc => "send req (to dst)",
+           cmd  => fun(#{sock_src := Sock, sa_dst := Dst, send := Send}) ->
+                           ok = Send(Sock, ?BASIC_REQ, Dst)
+                   end},
+         #{desc => "recv req (from src)",
+           cmd  => fun(#{sock_dst := Sock, sa_src := Src, recv := Recv}) ->
+                           {ok, {Src, ?BASIC_REQ}} = Recv(Sock),
+                           ok
+                   end},
+         #{desc => "send rep (to src)",
+           cmd  => fun(#{sock_dst := Sock, sa_src := Src, send := Send}) ->
+                           ok = Send(Sock, ?BASIC_REP, Src)
+                   end},
+         #{desc => "recv rep (from dst)",
+           cmd  => fun(#{sock_src := Sock, sa_dst := Dst, recv := Recv}) ->
+                           {ok, {Dst, ?BASIC_REP}} = Recv(Sock),
+                           ok
+                   end},
+         #{desc => "close src socket",
+           cmd  => fun(#{sock_src := Sock}) ->
+                           ok = socket:close(Sock)
+                   end},
+         #{desc => "close dst socket",
+           cmd  => fun(#{sock_dst := Sock}) ->
+                           ok = socket:close(Sock),
+                           {ok, normal}
+                   end}
+        ],
+    Evaluator = evaluator_start("tester", Seq, InitState),
+    ok = await_evaluator_finish([Evaluator]).
+
+
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+%% Basically send and receive using the "common" functions (send and recv)
+%% on an IPv4 TCP (stream) socket.
+api_b_send_and_recv_tcp4(suite) ->
+    [];
+api_b_send_and_recv_tcp4(doc) ->
+    [];
+api_b_send_and_recv_tcp4(_Config) when is_list(_Config) ->
+    ?TT(?SECS(10)),
+    tc_try(api_b_send_and_recv_tcp4,
+           fun() ->
+                   Send = fun(Sock, Data) ->
+                                  socket:send(Sock, Data)
+                          end,
+                   Recv = fun(Sock) ->
+                                  socket:recv(Sock)
+                          end,
+                   InitState = #{domain => inet,
+                                 send   => Send,
+                                 recv   => Recv},
+                   ok = api_b_send_and_recv_tcp(InitState)
+           end).
+
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+%% Basically send and receive using the msg functions (sendmsg and recvmsg)
+%% on an IPv4 TCP (stream) socket.
+api_b_sendmsg_and_recvmsg_tcp4(suite) ->
+    [];
+api_b_sendmsg_and_recvmsg_tcp4(doc) ->
+    [];
+api_b_sendmsg_and_recvmsg_tcp4(_Config) when is_list(_Config) ->
+    ?TT(?SECS(10)),
+    tc_try(api_b_sendmsg_and_recvmsg_tcp4,
+           fun() ->
+                   Send = fun(Sock, Data) ->
+                                  MsgHdr = #{iov => [Data]},
+                                  socket:sendmsg(Sock, MsgHdr)
+                          end,
+                   Recv = fun(Sock) ->
+                                  case socket:recvmsg(Sock) of
+                                      {ok, #{addr  := undefined,
+                                             iov   := [Data]}} ->
+                                          {ok, Data};
+                                      {error, _} = ERROR ->
+                                          ERROR
+                                  end
+                          end,
+                   InitState = #{domain => inet,
+                                 send   => Send,
+                                 recv   => Recv},
+                   ok = api_b_send_and_recv_tcp(InitState)
+           end).
+
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+api_b_send_and_recv_tcp(InitState) ->
+    process_flag(trap_exit, true),
+    ServerSeq = 
+        [
+         #{desc => "which local address",
+           cmd  => fun(#{domain := Domain} = State) ->
+                           LAddr = which_local_addr(Domain),
+                           LSA   = #{family => Domain, addr => LAddr},
+                           {ok, State#{lsa => LSA}}
+                   end},
+         #{desc => "create listen socket",
+           cmd  => fun(#{domain := Domain} = State) ->
+                           case socket:open(Domain, stream, tcp) of
+                               {ok, Sock} ->
+                                   {ok, State#{lsock => Sock}};
+                               {error, _} = ERROR ->
+                                   ERROR
+                           end
+                   end},
+         #{desc => "bind to local address",
+           cmd  => fun(#{lsock := LSock, lsa := LSA} = State) ->
+                           case socket:bind(LSock, LSA) of
+                               {ok, Port} ->
+                                   {ok, State#{lport => Port}};
+                               {error, _} = ERROR ->
+                                   ERROR
+                           end
+                   end},
+         #{desc => "make listen socket",
+           cmd  => fun(#{lsock := LSock}) ->
+                           socket:listen(LSock)
+                   end},
+         #{desc => "announce server port",
+           cmd  => fun(#{parent := Parent, lport := Port}) ->
+                           ei("announcing port to parent (~p)", [Parent]),
+                           Parent ! {server_port, self(), Port},
+                           ok
+                   end},
+         #{desc => "await connection",
+           cmd  => fun(#{lsock := LSock} = State) ->
+                           case socket:accept(LSock) of
+                               {ok, Sock} ->
+                                   ei("accepted: ~n   ~p", [Sock]),
+                                   {ok, State#{tsock => Sock}};
+                               {error, _} = ERROR ->
+                                   ERROR
+                           end
+                   end},
+         #{desc => "await request",
+           cmd  => fun(#{tsock := Sock, recv := Recv}) ->
+                           case Recv(Sock) of
+                               {ok, ?BASIC_REQ} ->
+                                   ok;
+                               {error, _} = ERROR ->
+                                   ERROR
+                           end
+                   end},
+         #{desc => "send reply",
+           cmd  => fun(#{tsock := Sock, send := Send}) ->
+                           Send(Sock, ?BASIC_REP)
+                   end},
+         #{desc => "sleep some",
+           cmd  => fun(_) ->
+                           ?SLEEP(1000),
+                           ok
+                   end},
+         #{desc => "close traffic socket",
+           cmd  => fun(#{tsock := Sock}) ->
+                           socket:close(Sock)
+                   end},
+         #{desc => "close listen socket",
+           cmd  => fun(#{lsock := Sock}) ->
+                           socket:close(Sock)
+                   end},
+         #{desc => "finish",
+           cmd  => fun(_) ->
+                           {ok, normal}
+                   end}
+        ],
+
+    ClientSeq = 
+        [
+         #{desc => "which server (local) address",
+           cmd  => fun(#{domain := Domain, server_port := Port} = State) ->
+                           LAddr = which_local_addr(Domain),
+                           LSA   = #{family => Domain, 
+                                     addr   => LAddr},
+                           SSA   = LSA#{port => Port},
+                           {ok, State#{lsa => LSA, ssa => SSA}}
+                   end},
+         #{desc => "create socket",
+           cmd  => fun(#{domain := Domain} = State) ->
+                           case socket:open(Domain, stream, tcp) of
+                               {ok, Sock} ->
+                                   {ok, State#{sock => Sock}};
+                               {error, _} = ERROR ->
+                                   ERROR
+                           end
+                   end},
+         #{desc => "bind to local address",
+           cmd  => fun(#{sock := Sock, lsa := LSA} = State) ->
+                           case socket:bind(Sock, LSA) of
+                               {ok, Port} ->
+                                   {ok, State#{port => Port}};
+                               {error, _} = ERROR ->
+                                   ERROR
+                           end
+                   end},
+         #{desc => "connect to server",
+           cmd  => fun(#{sock := Sock, ssa := SSA}) ->
+                           socket:connect(Sock, SSA)
+                   end},
+         #{desc => "send request (to server)",
+           cmd  => fun(#{sock := Sock, send := Send}) ->
+                           Send(Sock, ?BASIC_REQ)
+                   end},
+         #{desc => "recv reply (from server)",
+           cmd  => fun(#{sock := Sock, recv := Recv}) ->
+                           {ok, ?BASIC_REP} = Recv(Sock),
+                           ok
+                   end},
+         #{desc => "close socket",
+           cmd  => fun(#{sock := Sock}) ->
+                           socket:close(Sock)
+                   end},
+         #{desc => "finish",
+           cmd  => fun(_) ->
+                           {ok, normal}
+                   end}
+        ],
+
+    i("start server evaluator"),
+    #ev{pid = Pid} = Server = evaluator_start("server", ServerSeq, InitState),
+    i("await server (~p) port", [Pid]),
+    SPort = receive
+                {server_port, Pid, Port} ->
+                    Port
+            end,
+    i("start client evaluator"),
+    Client = evaluator_start("client", ClientSeq, InitState#{server_port => SPort}),
+    i("await evaluator(s)"),
+    ok = await_evaluator_finish([Server, Client]).
+
+
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%%                                                                     %%
+%%                           API OPTIONS                               %%
+%%                                                                     %%
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+%% Perform some simple getopt and setopt with the level = otp options
+api_opt_simple_otp_options(suite) ->
+    [];
+api_opt_simple_otp_options(doc) ->
+    [];
+api_opt_simple_otp_options(_Config) when is_list(_Config) ->
+    ?TT(?SECS(5)),
+    tc_try(api_opt_simple_otp_options,
+           fun() -> api_opt_simple_otp_options() end).
+
+api_opt_simple_otp_options() ->
+    Get = fun(S, Key) ->
+                  socket:getopt(S, otp, Key)
+          end,
+    Set = fun(S, Key, Val) ->
+                  socket:setopt(S, otp, Key, Val)
+          end,
+
+    Seq = 
+        [
+         %% *** Init part ***
+         #{desc => "create socket",
+           cmd  => fun(#{domain   := Domain, 
+                         type     := Type,
+                         protocol := Protocol} = State) ->
+                           Sock = sock_open(Domain, Type, Protocol),
+                           {ok, State#{sock => Sock}}
+                   end},
+         #{desc => "create dummy process",
+           cmd  => fun(State) ->
+                           Pid =  spawn_link(fun() -> 
+                                                     put(sname, "dummy"),
+                                                     receive
+                                                         die -> 
+                                                             exit(normal) 
+                                                     end 
+                                             end),
+                           {ok, State#{dummy => Pid}}
+                   end},
+
+         %% *** Check iow part ***
+         #{desc => "get iow",
+           cmd  => fun(#{sock := Sock} = State) ->
+                           case Get(Sock, iow) of
+                               {ok, IOW} when is_boolean(IOW) ->
+                                   {ok, State#{iow => IOW}};
+                               {ok, InvalidIOW} ->
+                                   {error, {invalid, InvalidIOW}};
+                               {error, _} = ERROR ->
+                                   ERROR
+                           end
+                   end},
+         #{desc => "set (new) iow",
+           cmd  => fun(#{sock := Sock, iow := OldIOW} = State) ->
+                           NewIOW = not OldIOW,
+                           case Set(Sock, iow, NewIOW) of
+                               ok ->
+                                   {ok, State#{iow => NewIOW}};
+                               {error, _} = ERROR ->
+                                   ERROR
+                           end
+                   end},
+         #{desc => "get (new) iow",
+           cmd  => fun(#{sock := Sock, iow := IOW}) ->
+                           case Get(Sock, iow) of
+                               {ok, IOW} ->
+                                   ok;
+                               {ok, InvalidIOW} ->
+                                   {error, {invalid, InvalidIOW}};
+                               {error, _} = ERROR ->
+                                   ERROR
+                           end
+                   end},
+
+         %% *** Check rcvbuf part ***
+         #{desc => "get rcvbuf",
+           cmd  => fun(#{sock := Sock} = State) ->
+                           case Get(Sock, rcvbuf) of
+                               {ok, RcvBuf} when is_integer(RcvBuf) ->
+                                   {ok, State#{rcvbuf => RcvBuf}};
+                               {ok, InvalidRcvBuf} ->
+                                   {error, {invalid, InvalidRcvBuf}};
+                               {error, _} = ERROR ->
+                                   ERROR
+                           end
+                   end},
+         #{desc => "set (new) rcvbuf",
+           cmd  => fun(#{sock := Sock, rcvbuf := OldRcvBuf} = State) ->
+                           NewRcvBuf = 2 * OldRcvBuf,
+                           case Set(Sock, rcvbuf, NewRcvBuf) of
+                               ok ->
+                                   {ok, State#{rcvbuf => NewRcvBuf}};
+                               {error, _} = ERROR ->
+                                   ERROR
+                           end
+                   end},
+         #{desc => "get (new) rcvbuf",
+           cmd  => fun(#{sock := Sock, rcvbuf := RcvBuf}) ->
+                           case Get(Sock, rcvbuf) of
+                               {ok, RcvBuf} ->
+                                   ok;
+                               {ok, InvalidRcvBuf} ->
+                                   {error, {invalid, InvalidRcvBuf}};
+                               {error, _} = ERROR ->
+                                   ERROR
+                           end
+                   end},
+
+         %% *** Check rcvctrlbuf part ***
+         #{desc => "get rcvctrlbuf",
+           cmd  => fun(#{sock := Sock} = State) ->
+                           case Get(Sock, rcvctrlbuf) of
+                               {ok, RcvCtrlBuf} when is_integer(RcvCtrlBuf) ->
+                                   {ok, State#{rcvctrlbuf => RcvCtrlBuf}};
+                               {ok, InvalidRcvCtrlBuf} ->
+                                   {error, {invalid, InvalidRcvCtrlBuf}};
+                               {error, _} = ERROR ->
+                                   ERROR
+                           end
+                   end},
+         #{desc => "set (new) rcvctrlbuf",
+           cmd  => fun(#{sock := Sock, rcvctrlbuf := OldRcvCtrlBuf} = State) ->
+                           NewRcvCtrlBuf = 2 * OldRcvCtrlBuf,
+                           case Set(Sock, rcvctrlbuf, NewRcvCtrlBuf) of
+                               ok ->
+                                   {ok, State#{rcvctrlbuf => NewRcvCtrlBuf}};
+                               {error, _} = ERROR ->
+                                   ERROR
+                           end
+                   end},
+         #{desc => "get (new) rcvctrlbuf",
+           cmd  => fun(#{sock := Sock, rcvctrlbuf := RcvCtrlBuf}) ->
+                           case Get(Sock, rcvctrlbuf) of
+                               {ok, RcvCtrlBuf} ->
+                                   ok;
+                               {ok, InvalidRcvCtrlBuf} ->
+                                   {error, {invalid, InvalidRcvCtrlBuf}};
+                               {error, _} = ERROR ->
+                                   ERROR
+                           end
+                   end},
+         %% *** Check rcvctrlbuf part ***
+         #{desc => "get rcvctrlbuf",
+           cmd  => fun(#{sock := Sock} = State) ->
+                           case Get(Sock, rcvctrlbuf) of
+                               {ok, RcvCtrlBuf} when is_integer(RcvCtrlBuf) ->
+                                   {ok, State#{rcvctrlbuf => RcvCtrlBuf}};
+                               {ok, InvalidRcvCtrlBuf} ->
+                                   {error, {invalid, InvalidRcvCtrlBuf}};
+                               {error, _} = ERROR ->
+                                   ERROR
+                           end
+                   end},
+         #{desc => "set (new) rcvctrlbuf",
+           cmd  => fun(#{sock := Sock, rcvctrlbuf := OldRcvCtrlBuf} = State) ->
+                           NewRcvCtrlBuf = 2 * OldRcvCtrlBuf,
+                           case Set(Sock, rcvctrlbuf, NewRcvCtrlBuf) of
+                               ok ->
+                                   {ok, State#{rcvctrlbuf => NewRcvCtrlBuf}};
+                               {error, _} = ERROR ->
+                                   ERROR
+                           end
+                   end},
+         #{desc => "get (new) rcvctrlbuf",
+           cmd  => fun(#{sock := Sock, rcvctrlbuf := RcvCtrlBuf}) ->
+                           case Get(Sock, rcvctrlbuf) of
+                               {ok, RcvCtrlBuf} ->
+                                   ok;
+                               {ok, InvalidRcvCtrlBuf} ->
+                                   {error, {invalid, InvalidRcvCtrlBuf}};
+                               {error, _} = ERROR ->
+                                   ERROR
+                           end
+                   end},
+
+
+         %% *** Check sndctrlbuf part ***
+         #{desc => "get sndctrlbuf",
+           cmd  => fun(#{sock := Sock} = State) ->
+                           case Get(Sock, sndctrlbuf) of
+                               {ok, SndCtrlBuf} when is_integer(SndCtrlBuf) ->
+                                   {ok, State#{sndctrlbuf => SndCtrlBuf}};
+                               {ok, InvalidSndCtrlBuf} ->
+                                   {error, {invalid, InvalidSndCtrlBuf}};
+                               {error, _} = ERROR ->
+                                   ERROR
+                           end
+                   end},
+         #{desc => "set (new) sndctrlbuf",
+           cmd  => fun(#{sock := Sock, sndctrlbuf := OldSndCtrlBuf} = State) ->
+                           NewSndCtrlBuf = 2 * OldSndCtrlBuf,
+                           case Set(Sock, sndctrlbuf, NewSndCtrlBuf) of
+                               ok ->
+                                   {ok, State#{sndctrlbuf => NewSndCtrlBuf}};
+                               {error, _} = ERROR ->
+                                   ERROR
+                           end
+                   end},
+         #{desc => "get (new) sndctrlbuf",
+           cmd  => fun(#{sock := Sock, sndctrlbuf := SndCtrlBuf}) ->
+                           case Get(Sock, sndctrlbuf) of
+                               {ok, SndCtrlBuf} ->
+                                   ok;
+                               {ok, InvalidSndCtrlBuf} ->
+                                   {error, {invalid, InvalidSndCtrlBuf}};
+                               {error, _} = ERROR ->
+                                   ERROR
+                           end
+                   end},
+
+         %% *** Check controlling-process part ***
+         #{desc => "verify self as controlling-process",
+           cmd  => fun(#{sock := Sock}) ->
+                           Self = self(),
+                           case Get(Sock, controlling_process) of
+                               {ok, Self} ->
+                                   ok;
+                               {ok, InvalidPid} ->
+                                   {error, {invalid, InvalidPid}};
+                               {error, _} = ERROR ->
+                                   ERROR
+                           end
+                   end},
+         #{desc => "set dummy as controlling-process",
+           cmd  => fun(#{sock := Sock, dummy := Dummy}) ->
+                           Set(Sock, controlling_process, Dummy)
+                   end},
+         #{desc => "verify dummy as controlling-process",
+           cmd  => fun(#{sock := Sock, dummy := Dummy}) ->
+                           case Get(Sock, controlling_process) of
+                               {ok, Dummy} ->
+                                   ok;
+                               {ok, InvalidPid} ->
+                                   {error, {invalid, InvalidPid}};
+                               {error, _} = ERROR ->
+                                   ERROR
+                           end
+                   end},
+
+         %% *** We are done ***
+         #{desc => "finish",
+           cmd  => fun(_) ->
+                           {ok, normal}
+                   end}
+        ],
+
+    i("start tcp (stream) evaluator"),
+    InitState1 = #{domain => inet, type => stream, protocol => tcp},
+    Tester1 = evaluator_start("tcp-tester", Seq, InitState1),
+    i("await tcp evaluator"),
+    ok = await_evaluator_finish([Tester1]),
+
+    i("start udp (dgram) socket"),
+    InitState2 = #{domain => inet, type => dgram, protocol => udp},
+    Tester2 = evaluator_start("udp-tester", Seq, InitState2),
+    i("await udp evaluator"),
+    ok = await_evaluator_finish([Tester2]).
+
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+%% Perform some simple getopt and setopt with the level = otp options
+api_opt_simple_otp_controlling_process(suite) ->
+    [];
+api_opt_simple_otp_controlling_process(doc) ->
+    [];
+api_opt_simple_otp_controlling_process(_Config) when is_list(_Config) ->
+    ?TT(?SECS(5)),
+    tc_try(api_opt_simple_otp_controlling_process,
+           fun() -> api_opt_simple_otp_controlling_process() end).
+
+api_opt_simple_otp_controlling_process() ->
+    Get = fun(S, Key) ->
+                  socket:getopt(S, otp, Key)
+          end,
+    Set = fun(S, Key, Val) ->
+                  socket:setopt(S, otp, Key, Val)
+          end,
+
+    ClientSeq =
+        [
+         %% *** Init part ***
+         #{desc => "await start",
+           cmd  => fun(State) ->
+                           receive
+                               {start, Tester, Socket} ->
+                                   {ok, State#{tester => Tester,
+                                               sock   => Socket}}
+                           end
+                   end},
+         #{desc => "verify tester as controlling-process",
+           cmd  => fun(#{tester := Tester, sock := Sock} = _State) ->
+                           case Get(Sock, controlling_process) of
+                               {ok, Tester} ->
+                                   ok;
+                               {ok, InvalidPid} ->
+                                   {error, {invalid, InvalidPid}};
+                               {error, _} = ERROR ->
+                                   ERROR
+                           end
+                   end},
+         #{desc => "attempt invalid controlling-process transfer (to self)",
+           cmd  => fun(#{sock := Sock} = _State) ->
+                           case Set(Sock, controlling_process, self()) of
+                               {error, not_owner} ->
+                                   ok;
+                               ok ->
+                                   {error, unexpected_success};
+                               {error, _} = ERROR ->
+                                   ERROR
+                           end
+                   end},
+         #{desc => "announce ready (1)",
+           cmd  => fun(#{tester := Tester} = _State) ->
+                           Tester ! {ready, self()},
+                           ok
+                   end},
+         #{desc => "await continue",
+           cmd  => fun(#{tester := Tester} = _State) ->
+                           receive
+                               {continue, Tester} ->
+                                   ok
+                           end
+                   end},
+         #{desc => "verify self as controlling-process",
+           cmd  => fun(#{sock := Sock} = _State) ->
+                           Self = self(),
+                           case Get(Sock, controlling_process) of
+                               {ok, Self} ->
+                                   ok;
+                               {ok, InvalidPid} ->
+                                   {error, {invalid, InvalidPid}};
+                               {error, _} = ERROR ->
+                                   ERROR
+                           end
+                   end},
+         #{desc => "attempt controlling-process transfer to tester",
+           cmd  => fun(#{tester := Tester, sock := Sock} = _State) ->
+                           Set(Sock, controlling_process, Tester)
+                   end},
+         #{desc => "attempt invalid controlling-process transfer (to self)",
+           cmd  => fun(#{sock := Sock} = _State) ->
+                           case Set(Sock, controlling_process, self()) of
+                               {error, not_owner} ->
+                                   ok;
+                               ok ->
+                                   {error, unexpected_success};
+                               {error, _} = ERROR ->
+                                   ERROR
+                           end
+                   end},
+         #{desc => "announce ready (2)",
+           cmd  => fun(#{tester := Tester} = _State) ->
+                           Tester ! {ready, self()},
+                           ok
+                   end},
+         #{desc => "await termination",
+           cmd  => fun(#{tester := Tester} = State) ->
+                           receive
+                               {terminate, Tester} ->
+                                   State1 = maps:remove(tester, State),
+                                   State2 = maps:remove(sock, State1),
+                                   {ok, State2}
+                           end
+                   end},
+
+         %% *** We are done ***
+         #{desc => "finish",
+           cmd  => fun(_) ->
+                           {ok, normal}
+                   end}
+        ],
+
+    TesterSeq =
+        [
+         %% *** Init part ***
+         #{desc => "create socket",
+           cmd  => fun(#{domain   := Domain, 
+                         type     := Type,
+                         protocol := Protocol} = State) ->
+                           Sock = sock_open(Domain, Type, Protocol),
+                           {ok, State#{sock => Sock}}
+                   end},
+         #{desc => "verify self as controlling-process",
+           cmd  => fun(#{sock := Sock} = _State) ->
+                           Self = self(),
+                           case Get(Sock, controlling_process) of
+                               {ok, Self} ->
+                                   ok;
+                               {ok, InvalidPid} ->
+                                   {error, {invalid, InvalidPid}};
+                               {error, _} = ERROR ->
+                                   ERROR
+                           end
+                   end},
+         #{desc => "order (client) start",
+           cmd  => fun(#{client := Client, sock := Sock} = _State) ->
+                           Client ! {start, self(), Sock},
+                           ok
+                   end},
+         #{desc => "await (client) ready (1)",
+           cmd  => fun(#{client := Client} = _State) ->
+                           receive
+                               {ready, Client} ->
+                                   ok
+                           end
+                   end},
+         #{desc => "attempt controlling-process transfer to client",
+           cmd  => fun(#{client := Client, sock := Sock} = _State) ->
+                           Set(Sock, controlling_process, Client)
+                   end},
+         #{desc => "verify client as controlling-process",
+           cmd  => fun(#{client := Client, sock := Sock} = _State) ->
+                           case Get(Sock, controlling_process) of
+                               {ok, Client} ->
+                                   ok;
+                               {ok, InvalidPid} ->
+                                   {error, {invalid, InvalidPid}};
+                               {error, _} = ERROR ->
+                                   ERROR
+                           end
+                   end},
+         #{desc => "attempt invalid controlling-process transfer (to self)",
+           cmd  => fun(#{sock := Sock} = _State) ->
+                           case Set(Sock, controlling_process, self()) of
+                               {error, not_owner} ->
+                                   ok;
+                               ok ->
+                                   {error, unexpected_success};
+                               {error, _} = ERROR ->
+                                   ERROR
+                           end
+                   end},
+         #{desc => "order (client) continue",
+           cmd  => fun(#{client := Client} = _State) ->
+                           Client ! {continue, self()},
+                           ok
+                   end},
+         #{desc => "await (client) ready (2)",
+           cmd  => fun(#{client := Client} = _State) ->
+                           receive
+                               {ready, Client} ->
+                                   ok
+                           end
+                   end},
+         #{desc => "verify self as controlling-process",
+           cmd  => fun(#{sock := Sock} = _State) ->
+                           Self = self(),
+                           case Get(Sock, controlling_process) of
+                               {ok, Self} ->
+                                   ok;
+                               {ok, InvalidPid} ->
+                                   {error, {invalid, InvalidPid}};
+                               {error, _} = ERROR ->
+                                   ERROR
+                           end
+                   end},
+         #{desc => "monitor client",
+           cmd  => fun(#{client := Client} = State) ->
+                           MRef = erlang:monitor(process, Client),
+                           {ok, State#{client_mref => MRef}}
+                   end},
+         #{desc => "order (client) terminate",
+           cmd  => fun(#{client := Client} = _State) ->
+                           Client ! {terminate, self()},
+                           ok
+                   end},
+         #{desc => "await (client) down",
+           cmd  => fun(#{client := Client} = State) ->
+                           receive
+                               {'DOWN', _, process, Client, _} ->
+                                   {ok, maps:remove(client, State)}
+                           end
+                   end},
+         #{desc => "close socket",
+           cmd  => fun(#{sock := Sock} = State) ->
+                           sock_close(Sock),
+                           {ok, maps:remove(sock, State)}
+                   end},
+
+         %% *** We are done ***
+         #{desc => "finish",
+           cmd  => fun(_) ->
+                           {ok, normal}
+                   end}
+        ],
+
+    i("start tcp (stream) socket"),
+    ClientInitState1 = #{},
+    #ev{pid = Pid1} = Client1 = evaluator_start("tcp-client", 
+                                                ClientSeq, ClientInitState1),
+    TesterInitState1 = #{domain   => inet, 
+                         type     => stream, 
+                         protocol => tcp,
+                         client   => Pid1},
+    Tester1          = evaluator_start("tcp-tester", TesterSeq, TesterInitState1),
+    i("await tcp evaluator"),
+    ok = await_evaluator_finish([Tester1, Client1]),
+
+    i("start udp (dgram) socket"),
+    ClientInitState2 = #{},
+    #ev{pid = Pid2} = Client2 = evaluator_start("udp-client", 
+                                                ClientSeq, ClientInitState2),
+    TesterInitState2 = #{domain   => inet, 
+                         type     => dgram, 
+                         protocol => udp,
+                         client   => Pid2},
+    Tester2          = evaluator_start("udp-tester", TesterSeq, TesterInitState2),
+    i("await udp evaluator"),
+    ok = await_evaluator_finish([Tester2, Client2]).
+
+
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%%                                                                     %%
+%%                  API OPERATIONS WITH TIMEOUT                        %%
+%%                                                                     %%
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+%% This test case is intended to test the connect timeout option
+%% on an IPv4 TCP (stream) socket.
+api_to_connect_tcp4(suite) ->
+    [];
+api_to_connect_tcp4(doc) ->
+    [];
+api_to_connect_tcp4(_Config) when is_list(_Config) ->
+    tc_try(api_to_connect_tcp4,
+           fun() ->
+                   ?TT(?SECS(10)),
+                   InitState = #{domain => inet, timeout => 5000},
+                   ok = api_to_connect_tcp(InitState)
+           end).
+
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+%% This test case is intended to test the connect timeout option
+%% on an IPv6 TCP (stream) socket.
+api_to_connect_tcp6(suite) ->
+    [];
+api_to_connect_tcp6(doc) ->
+    [];
+api_to_connect_tcp6(_Config) when is_list(_Config) ->
+    tc_try(api_to_connect_tcp6,
+           fun() ->
+                   not_yet_implemented(),
+                   ?TT(?SECS(10)),
+                   InitState = #{domain => inet6, timeout => 5000},
+                   ok = api_to_connect_tcp(InitState)
+           end).
+
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%% We use the backlog (listen) argument to test this.
+%% Note that the behaviour of the TCP "server side" can vary when 
+%% a client connect to a "busy" server (full backlog).
+%% For instance, on FreeBSD (11.2) the reponse when the backlog is full
+%% is a econreset.
+
+api_to_connect_tcp(InitState) ->
+    process_flag(trap_exit, true),
+
+    ServerSeq = 
+        [
+         %% *** Wait for start order part ***
+         #{desc => "await start (from tester)",
+           cmd  => fun(State) ->
+                           receive
+                               {start, Tester} when is_pid(Tester) ->
+                                   {ok, State#{tester => Tester}}
+                           end
+                   end},
+
+         %% *** Init part ***
+         #{desc => "which local address",
+           cmd  => fun(#{domain := Domain} = State) ->
+                           LAddr = which_local_addr(Domain),
+                           LSA   = #{family => Domain, addr => LAddr},
+                           {ok, State#{lsa => LSA}}
+                   end},
+         #{desc => "create listen socket",
+           cmd  => fun(#{domain := Domain} = State) ->
+                           case socket:open(Domain, stream, tcp) of
+                               {ok, Sock} ->
+                                   {ok, State#{lsock => Sock}};
+                               {error, _} = ERROR ->
+                                   ERROR
+                           end
+                   end},
+         #{desc => "bind to local address",
+           cmd  => fun(#{lsock := LSock, lsa := LSA} = State) ->
+                           case socket:bind(LSock, LSA) of
+                               {ok, Port} ->
+                                   {ok, State#{lport => Port}};
+                               {error, _} = ERROR ->
+                                   ERROR
+                           end
+                   end},
+         #{desc => "make listen socket (with backlog = 1)",
+           cmd  => fun(#{lsock := LSock}) ->
+                           socket:listen(LSock, 1)
+                   end},
+         #{desc => "monitor server",
+           cmd  => fun(#{tester := Tester} = State) ->
+                           MRef = erlang:monitor(process, Tester),
+                           {ok, State#{tester_mref => MRef}}
+                   end},
+         #{desc => "announce ready",
+           cmd  => fun(#{tester := Tester, lport := Port}) ->
+                           ei("announcing ready to tester (~p)", [Tester]),
+                           Tester ! {ready, self(), Port},
+                           ok
+                   end},
+         #{desc => "await terminate (from tester)",
+           cmd  => fun(#{tester := Tester} = State) ->
+                           receive
+                               {'DOWN', _, process, Tester, Reason} ->
+                                   ee("Unexpected DOWN regarding tester ~p: "
+                                      "~n   ~p", [Reason]),
+                                   {error, {unexpected_exit, tester}};
+                               {terminate, Tester} ->
+                                   {ok, maps:remove(tester, State)}
+                           end
+                   end},
+
+         %% *** We are done ***
+         #{desc => "finish",
+           cmd  => fun(_) ->
+                           {ok, normal}
+                   end}
+        ],
+
+    TesterSeq =
+        [
+         %% *** Init part ***
+         #{desc => "which local address",
+           cmd  => fun(#{domain := Domain} = State) ->
+                           LAddr = which_local_addr(Domain),
+                           LSA   = #{family => Domain, addr => LAddr},
+                           {ok, State#{lsa => LSA}}
+                   end},
+         #{desc => "create socket 1",
+           cmd  => fun(#{domain := Domain} = State) ->
+                           case socket:open(Domain, stream, tcp) of
+                               {ok, Sock} ->
+                                   {ok, State#{sock1 => Sock}};
+                               {error, _} = ERROR ->
+                                   ERROR
+                           end
+                   end},
+         #{desc => "create socket 2",
+           cmd  => fun(#{domain := Domain} = State) ->
+                           case socket:open(Domain, stream, tcp) of
+                               {ok, Sock} ->
+                                   {ok, State#{sock2 => Sock}};
+                               {error, _} = ERROR ->
+                                   ERROR
+                           end
+                   end},
+         #{desc => "create socket 3",
+           cmd  => fun(#{domain := Domain} = State) ->
+                           case socket:open(Domain, stream, tcp) of
+                               {ok, Sock} ->
+                                   {ok, State#{sock3 => Sock}};
+                               {error, _} = ERROR ->
+                                   ERROR
+                           end
+                   end},
+         #{desc => "bind socket 1 to local address",
+           cmd  => fun(#{sock1 := Sock, lsa := LSA} = _State) ->
+                           case socket:bind(Sock, LSA) of
+                               {ok, _} ->
+                                   ok;
+                               {error, _} = ERROR ->
+                                   ERROR
+                           end
+                   end},
+         #{desc => "bind socket 2 to local address",
+           cmd  => fun(#{sock2 := Sock, lsa := LSA} = _State) ->
+                           case socket:bind(Sock, LSA) of
+                               {ok, _} ->
+                                   ok;
+                               {error, _} = ERROR ->
+                                   ERROR
+                           end
+                   end},
+         #{desc => "bind socket 3 to local address",
+           cmd  => fun(#{sock3 := Sock, lsa := LSA} = _State) ->
+                           case socket:bind(Sock, LSA) of
+                               {ok, _} ->
+                                   ok;
+                               {error, _} = ERROR ->
+                                   ERROR
+                           end
+                   end},
+
+         %% *** Synchronize with the server ***
+         #{desc => "order (server) start",
+           cmd  => fun(#{server := Server}) ->
+                           Server ! {start, self()},
+                           ok
+                   end},
+         #{desc => "await ready (from server)",
+           cmd  => fun(#{server := Server, lsa := LSA} = State) ->
+                           receive
+                               {ready, Server, Port} ->
+                                   {ok, State#{ssa => LSA#{port => Port}}}
+                           end
+                   end},
+
+         %% *** Connect sequence ***
+         #{desc => "order (server) start",
+           cmd  => fun(#{sock1   := Sock1,
+                         sock2   := Sock2,
+                         sock3   := Sock3,
+                         ssa     := SSA,
+                         timeout := To}) ->
+                           Socks = [Sock1, Sock2, Sock3],
+                           api_to_connect_tcp_await_timeout(Socks, To, SSA)
+                   end},
+
+         %% *** Terminate server ***
+         #{desc => "monitor server",
+           cmd  => fun(#{server := Server} = State) ->
+                           MRef = erlang:monitor(process, Server),
+                           {ok, State#{server_mref => MRef}}
+                   end},
+         #{desc => "order (server) terminate",
+           cmd  => fun(#{server := Server} = _State) ->
+                           Server ! {terminate, self()},
+                           ok
+                   end},
+         #{desc => "await (server) down",
+           cmd  => fun(#{server := Server} = State) ->
+                           receive
+                               {'DOWN', _, process, Server, _} ->
+                                   State1 = maps:remove(server, State),
+                                   State2 = maps:remove(ssa, State1),
+                                   {ok, State2}
+                           end
+                   end},
+
+         %% *** Close our sockets ***
+         #{desc => "close socket 3",
+           cmd  => fun(#{sock3 := Sock} = State) ->
+                           sock_close(Sock),
+                           {ok, maps:remove(sock3, State)}
+
+                   end},
+         #{desc => "close socket 2",
+           cmd  => fun(#{sock2 := Sock} = State) ->
+                           sock_close(Sock),
+                           {ok, maps:remove(sock2, State)}
+
+                   end},
+         #{desc => "close socket 1",
+           cmd  => fun(#{sock1 := Sock} = State) ->
+                           sock_close(Sock),
+                           {ok, maps:remove(sock1, State)}
+
+                   end},
+
+         %% *** We are done ***
+         #{desc => "finish",
+           cmd  => fun(_) ->
+                           {ok, normal}
+                   end}
+        ],
+
+    i("create server evaluator"),
+    ServerInitState = InitState,
+    Server          = evaluator_start("server", ServerSeq, ServerInitState),
+
+    i("create tester evaluator"),
+    TesterInitState = InitState#{server => Server#ev.pid},
+    Tester          = evaluator_start("tester", TesterSeq, TesterInitState),
+
+    i("await evaluator(s)"),
+    ok = await_evaluator_finish([Server, Tester]).
+
+
+api_to_connect_tcp_await_timeout(Socks, To, ServerSA) ->
+    api_to_connect_tcp_await_timeout(Socks, To, ServerSA, 1).
+
+api_to_connect_tcp_await_timeout([], _To, _ServerSA, _ID) ->
+    ?FAIL(unexpected_success);
+api_to_connect_tcp_await_timeout([Sock|Socks], To, ServerSA, ID) ->
+    ei("~w: try connect", [ID]),
+    Start = t(),
+    case socket:connect(Sock, ServerSA, To) of
+        {error, timeout} ->
+            ei("expected timeout (~w)", [ID]),
+            Stop  = t(),
+            TDiff = tdiff(Start, Stop),
+            if
+                (TDiff >= To) ->
+                    ok;
+                true ->
+                    {error, {unexpected_timeout, TDiff, To}}
+            end;
+        {error, econnreset = Reason} ->
+            ei("failed connecting: ~p - giving up", [Reason]),
+            ok;
+        {error, Reason} ->
+            ee("failed connecting: ~p", [Reason]),
+            ?FAIL({connect, Reason});
+        ok ->
+            ei("unexpected success (~w) - try next", [ID]),
+            api_to_connect_tcp_await_timeout(Socks, To, ServerSA, ID+1)
+    end.
+        
+
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+%% This test case is intended to test the accept timeout option
+%% on an IPv4 TCP (stream) socket.
+api_to_accept_tcp4(suite) ->
+    [];
+api_to_accept_tcp4(doc) ->
+    [];
+api_to_accept_tcp4(_Config) when is_list(_Config) ->
+    tc_try(api_to_accept_tcp4,
+           fun() ->
+                   ?TT(?SECS(10)),
+                   InitState = #{domain => inet, timeout => 5000},
+                   ok = api_to_accept_tcp(InitState)
+           end).
+
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+%% This test case is intended to test the accept timeout option
+%% on an IPv6 TCP (stream) socket.
+api_to_accept_tcp6(suite) ->
+    [];
+api_to_accept_tcp6(doc) ->
+    [];
+api_to_accept_tcp6(_Config) when is_list(_Config) ->
+    tc_try(api_to_accept_tcp4,
+           fun() ->
+                   not_yet_implemented(),
+                   ?TT(?SECS(10)),
+                   InitState = #{domain => inet6, timeout => 5000},
+                   ok = api_to_accept_tcp(InitState)
+           end).
+
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+api_to_accept_tcp(InitState) ->
+    TesterSeq =
+        [
+         %% *** Init part ***
+         #{desc => "which local address",
+           cmd  => fun(#{domain := Domain} = State) ->
+                           LAddr = which_local_addr(Domain),
+                           LSA   = #{family => Domain, addr => LAddr},
+                           {ok, State#{lsa => LSA}}
+                   end},
+         #{desc => "create (listen) socket",
+           cmd  => fun(#{domain := Domain} = State) ->
+                           case socket:open(Domain, stream, tcp) of
+                               {ok, Sock} ->
+                                   {ok, State#{lsock => Sock}};
+                               {error, _} = ERROR ->
+                                   ERROR
+                           end
+                   end},
+         #{desc => "bind to local address",
+           cmd  => fun(#{lsock := LSock, lsa := LSA} = _State) ->
+                           case socket:bind(LSock, LSA) of
+                               {ok, _} ->
+                                   ok;
+                               {error, _} = ERROR ->
+                                   ERROR
+                           end
+                   end},
+         #{desc => "make listen socket",
+           cmd  => fun(#{lsock := LSock}) ->
+                           socket:listen(LSock)
+                   end},
+
+         %% *** The actual test part ***
+         #{desc => "attempt to accept (without success)",
+           cmd  => fun(#{lsock := LSock, timeout := To} = State) ->
+                           Start = t(),
+                           case socket:accept(LSock, To) of
+                               {error, timeout} ->
+                                   {ok, State#{start => Start, stop => t()}};
+                               {ok, Sock} ->
+                                   (catch socket:close(Sock)),
+                                   {error, unexpected_success};
+                               {error, _} = ERROR ->
+                                   ERROR
+                           end
+                   end},
+         #{desc => "validate timeout time",
+           cmd  => fun(#{start := Start, stop := Stop, timeout := To} = _State) ->
+                           TDiff  = tdiff(Start, Stop),
+                           if
+                               (TDiff >= To) ->
+                                   ok;
+                               true ->
+                                   {error, {unexpected_timeout, TDiff, To}}
+                           end
+                   end},
+
+         %% *** Close (listen) socket ***
+         #{desc => "close (listen) socket",
+           cmd  => fun(#{lsock := LSock} = State) ->
+                           sock_close(LSock),
+                           {ok, maps:remove(sock3, State)}
+                   end},
+
+         %% *** We are done ***
+         #{desc => "finish",
+           cmd  => fun(_) ->
+                           {ok, normal}
+                   end}
+        ],
+
+    i("create tester evaluator"),
+    Tester = evaluator_start("tester", TesterSeq, InitState),
+
+    i("await evaluator"),
+    ok = await_evaluator_finish([Tester]).
+
+
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+%% This test case is intended to test the multi accept timeout option
+%% on an IPv4 TCP (stream) socket with multiple acceptor processes 
+%% (three in this case).
+api_to_maccept_tcp4(suite) ->
+    [];
+api_to_maccept_tcp4(doc) ->
+    [];
+api_to_maccept_tcp4(_Config) when is_list(_Config) ->
+    tc_try(api_to_maccept_tcp4,
+           fun() ->
+                   InitState = #{domain => inet, timeout => 5000},
+                   ok = api_to_maccept_tcp(InitState)
+           end).
+
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+%% This test case is intended to test the accept timeout option
+%% on an IPv6 TCP (stream) socket.
+api_to_maccept_tcp6(suite) ->
+    [];
+api_to_maccept_tcp6(doc) ->
+    [];
+api_to_maccept_tcp6(_Config) when is_list(_Config) ->
+    tc_try(api_to_maccept_tcp4,
+           fun() ->
+                   not_yet_implemented(),
+                   InitState = #{domain => inet6, timeout => 5000},
+                   ok = api_to_maccept_tcp(InitState)
+           end).
+
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+api_to_maccept_tcp(InitState) ->
+    PrimAcceptorSeq =
+        [
+         %% *** Init part ***
+         #{desc => "await start",
+           cmd  => fun(State) ->
+                           receive
+                               {start, Tester} ->
+                                   MRef = erlang:monitor(process, Tester),
+                                   {ok, State#{tester      => Tester,
+                                               tester_mref => MRef}}
+                           end
+                   end},
+         #{desc => "which local address",
+           cmd  => fun(#{domain := Domain} = State) ->
+                           LAddr = which_local_addr(Domain),
+                           LSA   = #{family => Domain, addr => LAddr},
+                           {ok, State#{lsa => LSA}}
+                   end},
+         #{desc => "create (listen) socket",
+           cmd  => fun(#{domain := Domain} = State) ->
+                           case socket:open(Domain, stream, tcp) of
+                               {ok, Sock} ->
+                                   {ok, State#{lsock => Sock}};
+                               {error, _} = ERROR ->
+                                   ERROR
+                           end
+                   end},
+         #{desc => "bind to local address",
+           cmd  => fun(#{lsock := LSock, lsa := LSA} = _State) ->
+                           case socket:bind(LSock, LSA) of
+                               {ok, _} ->
+                                   ok;
+                               {error, _} = ERROR ->
+                                   ERROR
+                           end
+                   end},
+         #{desc => "make listen socket",
+           cmd  => fun(#{lsock := LSock}) ->
+                           socket:listen(LSock)
+                   end},
+
+         #{desc => "announce ready",
+           cmd  => fun(#{lsock := LSock, tester := Tester}) ->
+                           ei("announcing port to tester (~p)", [Tester]),
+                           Tester ! {ready, self(), LSock},
+                           ok
+                   end},
+         #{desc => "await continue",
+           cmd  => fun(#{tester := Tester} = _State) ->
+                           receive
+                               {'DOWN', _, process, Tester, Reason} ->
+                                   ee("Unexpected DOWN regarding tester ~p: "
+                                      "~n   ~p", [Reason]),
+                                   {error, {unexpected_exit, tester}};
+                               {continue, Tester} ->
+                                   ok
+                           end
+                   end},
+
+         %% *** The actual test part ***
+         #{desc => "attempt to accept (without success)",
+           cmd  => fun(#{lsock := LSock, timeout := To} = State) ->
+                           Start = t(),
+                           case socket:accept(LSock, To) of
+                               {error, timeout} ->
+                                   {ok, State#{start => Start, stop => t()}};
+                               {ok, Sock} ->
+                                   (catch socket:close(Sock)),
+                                   {error, unexpected_success};
+                               {error, _} = ERROR ->
+                                   ERROR
+                           end
+                   end},
+         #{desc => "validate timeout time",
+           cmd  => fun(#{start := Start, stop := Stop, timeout := To} = _State) ->
+                           TDiff  = tdiff(Start, Stop),
+                           if
+                               (TDiff >= To) ->
+                                   ok;
+                               true ->
+                                   {error, {unexpected_timeout, TDiff, To}}
+                           end
+                   end},
+         #{desc => "announce ready",
+           cmd  => fun(#{tester := Tester}) ->
+                           ei("announcing port to tester (~p)", [Tester]),
+                           Tester ! {ready, self()},
+                           ok
+                   end},
+         #{desc => "await terminate",
+           cmd  => fun(#{tester := Tester} = _State) ->
+                           receive
+                               {'DOWN', _, process, Tester, Reason} ->
+                                   ee("Unexpected DOWN regarding tester ~p: "
+                                      "~n   ~p", [Reason]),
+                                   {error, {unexpected_exit, tester}};
+                               {terminate, Tester} ->
+                                   ok
+                           end
+                   end},
+
+         %% *** Close (listen) socket ***
+         #{desc => "close (listen) socket",
+           cmd  => fun(#{lsock := LSock} = State) ->
+                           sock_close(LSock),
+                           {ok, maps:remove(lsock, State)}
+                   end},
+
+         %% *** We are done ***
+         #{desc => "finish",
+           cmd  => fun(_) ->
+                           {ok, normal}
+                   end}
+        ],
+
+
+    SecAcceptorSeq =
+        [
+         %% *** Init part ***
+         #{desc => "await start",
+           cmd  => fun(State) ->
+                           receive
+                               {start, Tester, LSock} ->
+                                   MRef = erlang:monitor(process, Tester),
+                                   {ok, State#{tester      => Tester,
+                                               lsock       => LSock,
+                                               tester_mref => MRef}}
+                           end
+                   end},
+         #{desc => "announce ready (1)",
+           cmd  => fun(#{tester := Tester} = _State) ->
+                           Tester ! {ready, self()},
+                           ok
+                   end},
+         #{desc => "await continue",
+           cmd  => fun(#{tester := Tester} = _State) ->
+                           receive
+                               {'DOWN', _, process, Tester, Reason} ->
+                                   ee("Unexpected DOWN regarding tester ~p: "
+                                      "~n   ~p", [Reason]),
+                                   {error, {unexpected_exit, tester, Reason}};
+                               {continue, Tester} ->
+                                   ok
+                           end
+                   end},
+
+         %% *** The actual test part ***
+         #{desc => "attempt to accept (without success)",
+           cmd  => fun(#{lsock := LSock, timeout := To} = State) ->
+                           Start = t(),
+                           case socket:accept(LSock, To) of
+                               {error, timeout} ->
+                                   {ok, State#{start => Start, stop => t()}};
+                               {ok, Sock} ->
+                                   (catch socket:close(Sock)),
+                                   {error, unexpected_success};
+                               {error, _} = ERROR ->
+                                   ERROR
+                           end
+                   end},
+         #{desc => "validate timeout time",
+           cmd  => fun(#{start := Start, stop := Stop, timeout := To} = _State) ->
+                           TDiff  = tdiff(Start, Stop),
+                           if
+                               (TDiff >= To) ->
+                                   ok;
+                               true ->
+                                   {error, {unexpected_timeout, TDiff, To}}
+                           end
+                   end},
+         #{desc => "announce ready (2)",
+           cmd  => fun(#{tester := Tester} = _State) ->
+                           Tester ! {ready, self()},
+                           ok
+                   end},
+         #{desc => "await terminate",
+           cmd  => fun(#{tester := Tester} = _State) ->
+                           receive
+                               {'DOWN', _, process, Tester, Reason} ->
+                                   ee("Unexpected DOWN regarding tester ~p: "
+                                      "~n   ~p", [Reason]),
+                                   {error, {unexpected_exit, tester, Reason}};
+                               {terminate, Tester} ->
+                                   ok
+                           end
+                   end},
+
+         %% *** We are done ***
+         #{desc => "finish",
+           cmd  => fun(_) ->
+                           {ok, normal}
+                   end}
+        ],
+
+
+    TesterSeq =
+        [
+         %% Init part
+         #{desc => "monitor prim-acceptor",
+           cmd  => fun(#{prim_acceptor := Pid} = _State) ->
+                           _MRef = erlang:monitor(process, Pid),
+                           ok
+                   end},
+         #{desc => "monitor sec-acceptor 1",
+           cmd  => fun(#{sec_acceptor1 := Pid} = _State) ->
+                           _MRef = erlang:monitor(process, Pid),
+                           ok
+                   end},
+         #{desc => "monitor sec-acceptor 2",
+           cmd  => fun(#{sec_acceptor2 := Pid} = _State) ->
+                           _MRef = erlang:monitor(process, Pid),
+                           ok
+                   end},
+
+
+         %% Start the prim-acceptor
+         #{desc => "start prim-acceptor",
+           cmd  => fun(#{prim_acceptor := Pid} = _State) ->
+                           Pid ! {start, self()},
+                           ok
+                   end},
+         #{desc => "await prim-acceptor ready (1)",
+           cmd  => fun(#{prim_acceptor := Pid} = State) ->
+                           receive
+                               {'DOWN', _, process, Pid, Reason} ->
+                                   ee("Unexpected DOWN regarding prim-acceptor ~p:"
+                                      "~n   ~p", [Reason]),
+                                   {error, {unexpected_exit, prim_acceptor}};
+                               {ready, Pid, LSock} ->
+                                   {ok, State#{lsock => LSock}}
+                           end
+                   end},
+
+         %% Start sec-acceptor-1
+         #{desc => "start sec-acceptor 1",
+           cmd  => fun(#{sec_acceptor1 := Pid, lsock := LSock} = _State) ->
+                           Pid ! {start, self(), LSock},
+                           ok
+                   end},
+         #{desc => "await sec-acceptor 1 ready (1)",
+           cmd  => fun(#{sec_acceptor1 := Pid} = _State) ->
+                           receive
+                               {'DOWN', _, process, Pid, Reason} ->
+                                   ee("Unexpected DOWN regarding sec-acceptor 1 ~p:"
+                                      "~n   ~p", [Reason]),
+                                   {error, {unexpected_exit, sec_acceptor_1}};
+                               {ready, Pid} ->
+                                   ok
+                           end
+                   end},
+
+         %% Start sec-acceptor-2
+         #{desc => "start sec-acceptor 2",
+           cmd  => fun(#{sec_acceptor2 := Pid, lsock := LSock} = _State) ->
+                           Pid ! {start, self(), LSock},
+                           ok
+                   end},
+         #{desc => "await sec-acceptor 2 ready (1)",
+           cmd  => fun(#{sec_acceptor2 := Pid} = _State) ->
+                           receive
+                               {'DOWN', _, process, Pid, Reason} ->
+                                   ee("Unexpected DOWN regarding sec-acceptor 2 ~p:"
+                                      "~n   ~p", [Reason]),
+                                   {error, {unexpected_exit, sec_acceptor_2}};
+                               {ready, Pid} ->
+                                   ok
+                           end
+                   end},
+
+         %% Activate the acceptor(s)
+         #{desc => "active prim-acceptor",
+           cmd  => fun(#{prim_acceptor := Pid} = _State) ->
+                           Pid ! {continue, self()},
+                           ok
+                   end},
+         #{desc => "active sec-acceptor 1",
+           cmd  => fun(#{sec_acceptor1 := Pid} = _State) ->
+                           Pid ! {continue, self()},
+                           ok
+                   end},
+         #{desc => "active sec-acceptor 2",
+           cmd  => fun(#{sec_acceptor2 := Pid} = _State) ->
+                           Pid ! {continue, self()},
+                           ok
+                   end},
+
+         %% Await acceptor(s) completions
+         #{desc => "await prim-acceptor ready (2)",
+           cmd  => fun(#{prim_acceptor := Pid} = _State) ->
+                           receive
+                               {'DOWN', _, process, Pid, Reason} ->
+                                   ee("Unexpected DOWN regarding prim-acceptor ~p:"
+                                      "~n   ~p", [Reason]),
+                                   {error, {unexpected_exit, prim_acceptor}};
+                               {ready, Pid} ->
+                                   ok
+                           end
+                   end},
+         #{desc => "await sec-acceptor 1 ready (2)",
+           cmd  => fun(#{sec_acceptor1 := Pid} = _State) ->
+                           receive
+                               {'DOWN', _, process, Pid, Reason} ->
+                                   ee("Unexpected DOWN regarding sec-acceptor 1 ~p:"
+                                      "~n   ~p", [Reason]),
+                                   {error, {unexpected_exit, sec_acceptor_1}};
+                               {ready, Pid} ->
+                                   ok
+                           end
+                   end},
+         #{desc => "await sec-acceptor 2 ready (2)",
+           cmd  => fun(#{sec_acceptor2 := Pid} = _State) ->
+                           receive
+                               {'DOWN', _, process, Pid, Reason} ->
+                                   ee("Unexpected DOWN regarding sec-acceptor 2 ~p:"
+                                      "~n   ~p", [Reason]),
+                                   {error, {unexpected_exit, sec_acceptor_2}};
+                               {ready, Pid} ->
+                                   ok
+                           end
+                   end},
+
+
+         %% Terminate the acceptor(s)
+         #{desc => "order prim-acceptor to terminate",
+           cmd  => fun(#{prim_acceptor := Pid} = _State) ->
+                           ei("send terminate command to prim-acceptor (~p)", [Pid]),
+                           Pid ! {terminate, self()},
+                           ok
+                   end},
+         #{desc => "order sec-acceptor 1 to terminate",
+           cmd  => fun(#{sec_acceptor1 := Pid} = _State) ->
+                           ei("send terminate command to sec-acceptor-1 (~p)", [Pid]),
+                           Pid ! {terminate, self()},
+                           ok
+                   end},
+         #{desc => "order sec-acceptor 2 to terminate",
+           cmd  => fun(#{sec_acceptor2 := Pid} = _State) ->
+                           ei("send terminate command to sec-acceptor-2 (~p)", [Pid]),
+                           Pid ! {terminate, self()},
+                           ok
+                   end},
+
+         %% Await acceptor(s) termination
+         #{desc => "await prim-acceptor termination",
+           cmd  => fun(#{prim_acceptor := Pid} = State) ->
+                           receive
+                               {'DOWN', _, process, Pid, _} ->
+                                   State1 = maps:remove(prim_acceptor, State),
+                                   {ok, State1}
+                           end
+                   end},
+         #{desc => "await sec-acceptor 1 termination",
+           cmd  => fun(#{sec_acceptor1 := Pid} = State) ->
+                           receive
+                               {'DOWN', _, process, Pid, _} ->
+                                   State1 = maps:remove(sec_acceptor1, State),
+                                   {ok, State1}
+                           end
+                   end},
+         #{desc => "await sec-acceptor 2 termination",
+           cmd  => fun(#{sec_acceptor2 := Pid} = State) ->
+                           receive
+                               {'DOWN', _, process, Pid, _} ->
+                                   State1 = maps:remove(sec_acceptor2, State),
+                                   {ok, State1}
+                           end
+                   end},
+         
+         %% *** We are done ***
+         #{desc => "finish",
+           cmd  => fun(_) ->
+                           {ok, normal}
+                   end}
+        ],
+
+    i("create prim-acceptor evaluator"),
+    PrimAInitState = InitState,
+    #ev{pid = PPid} = PrimAcceptor = evaluator_start("prim-acceptor", 
+                                                     PrimAcceptorSeq, 
+                                                     PrimAInitState),
+
+    i("create sec-acceptor 1 evaluator"),
+    SecAInitState1 = maps:remove(domain, InitState),
+    #ev{pid = SPid1} = SecAcceptor1 = evaluator_start("sec-acceptor-1", 
+                                                      SecAcceptorSeq, 
+                                                      SecAInitState1),
+    
+    i("create sec-acceptor 2 evaluator"),
+    SecAInitState2 = SecAInitState1,
+    #ev{pid = SPid2} = SecAcceptor2 = evaluator_start("sec-acceptor-2", 
+                                                      SecAcceptorSeq, 
+                                                      SecAInitState2),
+
+    i("create tester evaluator"),
+    TesterInitState = #{prim_acceptor => PPid,
+                        sec_acceptor1 => SPid1,
+                        sec_acceptor2 => SPid2},
+    Tester = evaluator_start("tester", TesterSeq, TesterInitState),
+
+    i("await evaluator(s)"),
+    ok = await_evaluator_finish([PrimAcceptor, SecAcceptor1, SecAcceptor2, Tester]).
+
+
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+%% This test case is intended to test the send timeout option
+%% on an IPv4 TCP (stream) socket.
+api_to_send_tcp4(suite) ->
+    [];
+api_to_send_tcp4(doc) ->
+    [];
+api_to_send_tcp4(_Config) when is_list(_Config) ->
+    tc_try(api_to_send_tcp4,
+           fun() ->
+                   not_yet_implemented()%% ,
+                   %% ok = api_to_send_tcp(inet)
+           end).
+
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+%% This test case is intended to test the send timeout option
+%% on an IPv6 TCP (stream) socket.
+api_to_send_tcp6(suite) ->
+    [];
+api_to_send_tcp6(doc) ->
+    [];
+api_to_send_tcp6(_Config) when is_list(_Config) ->
+    tc_try(api_to_send_tcp6,
+           fun() ->
+                   not_yet_implemented()%% ,
+                   %% ok = api_to_send_tcp(inet6)
+           end).
+
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+%% This test case is intended to test the sendto timeout option
+%% on an IPv4 UDP (dgram) socket.
+api_to_sendto_udp4(suite) ->
+    [];
+api_to_sendto_udp4(doc) ->
+    [];
+api_to_sendto_udp4(_Config) when is_list(_Config) ->
+    tc_try(api_to_sendto_udp4,
+           fun() ->
+                   not_yet_implemented()%% ,
+                   %% ok = api_to_sendto_to_udp(inet)
+           end).
+
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+%% This test case is intended to test the sendto timeout option
+%% on an IPv6 UDP (dgram) socket.
+api_to_sendto_udp6(suite) ->
+    [];
+api_to_sendto_udp6(doc) ->
+    [];
+api_to_sendto_udp6(_Config) when is_list(_Config) ->
+    tc_try(api_to_sendto_udp6,
+           fun() ->
+                   not_yet_implemented()%% ,
+                   %% ok = api_to_sendto_to_udp(inet6)
+           end).
+
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+%% This test case is intended to test the sendmsg timeout option
+%% on an IPv4 TCP (stream) socket.
+api_to_sendmsg_tcp4(suite) ->
+    [];
+api_to_sendmsg_tcp4(doc) ->
+    [];
+api_to_sendmsg_tcp4(_Config) when is_list(_Config) ->
+    tc_try(api_to_sendmsg_tcp4,
+           fun() ->
+                   not_yet_implemented()%% ,
+                   %% ok = api_to_sendmsg_tcp(inet)
+           end).
+
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+%% This test case is intended to test the sendmsg timeout option
+%% on an IPv6 TCP (stream) socket.
+api_to_sendmsg_tcp6(suite) ->
+    [];
+api_to_sendmsg_tcp6(doc) ->
+    [];
+api_to_sendmsg_tcp6(_Config) when is_list(_Config) ->
+    tc_try(api_to_sendmsg_tcp6,
+           fun() ->
+                   not_yet_implemented()%% ,
+                   %% ok = api_to_sendmsg_tcp(inet6)
+           end).
+
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+%% This test case is intended to test the recv timeout option
+%% on an IPv4 UDP (dgram) socket. To test this we must connect
+%% the socket.
+api_to_recv_udp4(suite) ->
+    [];
+api_to_recv_udp4(doc) ->
+    [];
+api_to_recv_udp4(_Config) when is_list(_Config) ->
+    tc_try(api_to_recv_udp4,
+           fun() ->
+                   not_yet_implemented()%%,
+                   %%ok = api_to_recv_udp(inet)
+           end).
+
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+%% This test case is intended to test the recv timeout option
+%% on an IPv6 UDP (dgram) socket. To test this we must connect
+%% the socket.
+api_to_recv_udp6(suite) ->
+    [];
+api_to_recv_udp6(doc) ->
+    [];
+api_to_recv_udp6(_Config) when is_list(_Config) ->
+    tc_try(api_to_recv_udp6,
+           fun() ->
+                   not_yet_implemented()%% ,
+                   %% ok = api_to_recv_udp(inet6)
+           end).
+
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+%% This test case is intended to test the recv timeout option
+%% on an IPv4 TCP (stream) socket.
+api_to_recv_tcp4(suite) ->
+    [];
+api_to_recv_tcp4(doc) ->
+    [];
+api_to_recv_tcp4(_Config) when is_list(_Config) ->
+    tc_try(api_to_recv_tcp4,
+           fun() ->
+                   ?TT(?SECS(10)),
+                   Recv = fun(Sock, To) -> socket:recv(Sock, 0, To) end,
+                   InitState = #{domain  => inet,
+                                 recv    => Recv,
+                                 timeout => 5000},
+                   ok = api_to_receive_tcp(InitState)
+           end).
+
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+%% This test case is intended to test the recv timeout option
+%% on an IPv6 TCP (stream) socket.
+api_to_recv_tcp6(suite) ->
+    [];
+api_to_recv_tcp6(doc) ->
+    [];
+api_to_recv_tcp6(_Config) when is_list(_Config) ->
+    tc_try(api_to_recv_tcp6,
+           fun() ->
+                   not_yet_implemented(),
+                   case socket:supports(ipv6) of
+                       true ->
+                           ?TT(?SECS(10)),
+                           Recv = fun(Sock, To) -> 
+                                          socket:recv(Sock, 0, To)
+                                  end,
+                           InitState = #{domain  => inet6,
+                                         recv    => Recv,
+                                         timeout => 5000},
+                           ok = api_to_receive_tcp(InitState);
+                       false ->
+                           skip("ipv6 not supported")
+                   end
+           end).
+
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+api_to_receive_tcp(InitState) ->
+    process_flag(trap_exit, true),
+
+    ServerSeq = 
+        [
+         %% *** Wait for start order ***
+         #{desc => "await start (from tester)",
+           cmd  => fun(State) ->
+                           receive
+                               {start, Tester} when is_pid(Tester) ->
+                                   {ok, State#{tester => Tester}}
+                           end
+                   end},
+
+         %% *** Init part ***
+         #{desc => "which local address",
+           cmd  => fun(#{domain := Domain} = State) ->
+                           LAddr = which_local_addr(Domain),
+                           LSA   = #{family => Domain, addr => LAddr},
+                           {ok, State#{lsa => LSA}}
+                   end},
+         #{desc => "create listen socket",
+           cmd  => fun(#{domain := Domain} = State) ->
+                           case socket:open(Domain, stream, tcp) of
+                               {ok, Sock} ->
+                                   {ok, State#{lsock => Sock}};
+                               {error, _} = ERROR ->
+                                   ERROR
+                           end
+                   end},
+         #{desc => "bind to local address",
+           cmd  => fun(#{lsock := LSock, lsa := LSA} = State) ->
+                           case socket:bind(LSock, LSA) of
+                               {ok, Port} ->
+                                   {ok, State#{lport => Port}};
+                               {error, _} = ERROR ->
+                                   ERROR
+                           end
+                   end},
+         #{desc => "make listen socket (with backlog = 1)",
+           cmd  => fun(#{lsock := LSock}) ->
+                           socket:listen(LSock, 1)
+                   end},
+         #{desc => "monitor tester",
+           cmd  => fun(#{tester := Tester} = State) ->
+                           MRef = erlang:monitor(process, Tester),
+                           {ok, State#{tester_mref => MRef}}
+                   end},
+         #{desc => "announce ready",
+           cmd  => fun(#{tester := Tester, lport := Port}) ->
+                           Tester ! {ready, self(), Port},
+                           ok
+                   end},
+         #{desc => "await continue",
+           cmd  => fun(#{tester := Tester}) ->
+                           receive
+                               {'DOWN', _, process, Tester, Reason} ->
+                                   {error, {unexpected_exit, tester, Reason}};
+                               {continue, Tester} ->
+                                   ok
+                           end
+                   end},
+
+         %% *** The actual test ***
+         #{desc => "await accept",
+           cmd  => fun(#{lsock := LSock} = State) ->
+                           case socket:accept(LSock) of
+                               {ok, Sock} ->
+                                   %% ok = socket:setopt(Sock, otp, debug, true),
+                                   {ok, State#{sock => Sock}};
+                               {error, _} = ERROR ->
+                                   ERROR
+                           end
+                   end},
+         #{desc => "attempt to recv (without success)",
+           cmd  => fun(#{sock := Sock, recv := Recv, timeout := To} = State) ->
+                           Start = t(),
+                           case Recv(Sock, To) of
+                               {error, timeout} ->
+                                   {ok, State#{start => Start, stop => t()}};
+                               {ok, _Data} ->
+                                   {error, unexpected_success};
+                               {error, _} = ERROR ->
+                                   ERROR
+                           end
+                   end},
+         #{desc => "validate timeout time",
+           cmd  => fun(#{start := Start, stop := Stop, timeout := To} = _State) ->
+                           TDiff  = tdiff(Start, Stop),
+                           if
+                               (TDiff >= To) ->
+                                   ok;
+                               true ->
+                                   {error, {unexpected_timeout, TDiff, To}}
+                           end
+                   end},
+         #{desc => "announce ready (recv timeout success)",
+           cmd  => fun(#{tester := Tester} = _State) ->
+                           Tester ! {ready, self()},
+                           ok
+                   end},
+
+         %% *** Termination ***
+         #{desc => "await terminate",
+           cmd  => fun(#{tester := Tester} = State) ->
+                           receive
+                               {'DOWN', _, process, Tester, Reason} ->
+                                   {error, {unexpected_exit, tester, Reason}};
+                               {terminate, Tester} ->
+                                   {ok, maps:remove(tester, State)}
+                           end
+                   end},
+         %% #{desc => "sleep some (before traffic close)",
+         %%   cmd  => fun(_) ->
+         %%                   ?SLEEP(1000),
+         %%                   ok
+         %%           end},
+         %% #{desc => "monitored-by",
+         %%   cmd  => fun(_) ->
+         %%                   {_, Mons} = process_info(self(), monitored_by),
+         %%                   ei("Monitored By: ~p", [Mons]),
+         %%                   ok
+         %%           end},
+         #{desc => "close (traffic) socket",
+           cmd  => fun(#{sock := Sock} = State) ->
+                           %% ok = socket:setopt(Sock, otp, debug, true),
+                           sock_close(Sock),
+                           {ok, maps:remove(sock, State)}
+                   end},
+         %% #{desc => "monitored-by",
+         %%   cmd  => fun(_) ->
+         %%                   {_, Mons} = process_info(self(), monitored_by),
+         %%                   ei("Monitored By: ~p", [Mons]),
+         %%                   ok
+         %%           end},
+         %% #{desc => "sleep some (before listen close)",
+         %%   cmd  => fun(_) ->
+         %%                   ?SLEEP(1000),
+         %%                   ok
+         %%           end},
+         #{desc => "close (listen) socket",
+           cmd  => fun(#{lsock := LSock} = State) ->
+                           sock_close(LSock),
+                           {ok, maps:remove(lsock, State)}
+                   end},
+         %% #{desc => "sleep some (after listen close)",
+         %%   cmd  => fun(_) ->
+         %%                   ?SLEEP(1000),
+         %%                   ok
+         %%           end},
+
+         %% *** We are done ***
+         #{desc => "finish",
+           cmd  => fun(_) ->
+                           {ok, normal}
+                   end}
+        ],
+
+    ClientSeq =
+        [
+         %% *** Wait for start order part ***
+         #{desc => "await start (from tester)",
+           cmd  => fun(State) ->
+                           receive
+                               {start, Tester, Port} when is_pid(Tester) ->
+                                   {ok, State#{tester      => Tester,
+                                               server_port => Port}}
+                           end
+                   end},
+
+         %% *** Init part ***
+         #{desc => "which local address",
+           cmd  => fun(#{domain := Domain, server_port := Port} = State) ->
+                           LAddr = which_local_addr(Domain),
+                           LSA   = #{family => Domain,
+                                     addr   => LAddr},
+                           SSA   = LSA#{port => Port},
+                           {ok, State#{lsa => LSA, ssa => SSA}}
+                   end},
+         #{desc => "create socket",
+           cmd  => fun(#{domain := Domain} = State) ->
+                           case socket:open(Domain, stream, tcp) of
+                               {ok, Sock} ->
+                                   {ok, State#{sock => Sock}};
+                               {error, _} = ERROR ->
+                                   ERROR
+                           end
+                   end},
+         #{desc => "bind to local address",
+           cmd  => fun(#{sock := Sock, lsa := LSA} = _State) ->
+                           case socket:bind(Sock, LSA) of
+                               {ok, _} ->
+                                   ok;
+                               {error, _} = ERROR ->
+                                   ERROR
+                           end
+                   end},
+         #{desc => "monitor tester",
+           cmd  => fun(#{tester := Tester} = State) ->
+                           MRef = erlang:monitor(process, Tester),
+                           {ok, State#{tester_mref => MRef}}
+                   end},
+         #{desc => "announce ready",
+           cmd  => fun(#{tester := Tester} = _State) ->
+                           Tester ! {ready, self()},
+                           ok
+                   end},
+
+         %% *** The actual test ***
+         #{desc => "await continue (with connect)",
+           cmd  => fun(#{tester := Tester} = _State) ->
+                           receive
+                               {'DOWN', _, process, Tester, Reason} ->
+                                   {error, {unexpected_exit, tester, Reason}};
+                               {continue, Tester} ->
+                                   ok
+                           end
+                   end},
+         #{desc => "connect",
+           cmd  => fun(#{sock := Sock, ssa := SSA}) ->
+                           sock_connect(Sock, SSA),
+                           ok
+                   end},
+
+         %% *** Termination ***
+         #{desc => "await terminate",
+           cmd  => fun(#{tester := Tester} = State) ->
+                           receive
+                               {'DOWN', _, process, Tester, Reason} ->
+                                   {error, {unexpected_exit, tester, Reason}};
+                               {terminate, Tester} ->
+                                   {ok, maps:remove(tester, State)}
+                           end
+                   end},
+         #{desc => "close socket",
+           cmd  => fun(#{sock := Sock} = State) ->
+                           sock_close(Sock),
+                           {ok, maps:remove(sock, State)}
+                   end},
+
+         %% *** We are done ***
+         #{desc => "finish",
+           cmd  => fun(_) ->
+                           {ok, normal}
+                   end}
+        ],
+
+    TesterSeq =
+        [
+         %% *** Init part ***
+         #{desc => "monitor server",
+           cmd  => fun(#{server := Server} = State) ->
+                           MRef = erlang:monitor(process, Server),
+                           {ok, State#{server_mref => MRef}}
+                   end},
+         #{desc => "monitor client",
+           cmd  => fun(#{client := Client} = State) ->
+                           MRef = erlang:monitor(process, Client),
+                           {ok, State#{client_mref => MRef}}
+                   end},
+
+         %% *** Activate server ***
+         #{desc => "start server",
+           cmd  => fun(#{server := Server} = _State) ->
+                           Server ! {start, self()},
+                           ok
+                   end},
+         #{desc => "await server ready (init)",
+           cmd  => fun(#{server := Server} = State) ->
+                           receive
+                               {'DOWN', _, process, Server, Reason} ->
+                                   {error, {unexpected_exit, server, Reason}};
+                               {ready, Server, Port} ->
+                                   {ok, State#{server_port => Port}}
+                           end
+                   end},
+         #{desc => "order server to continue (with accept)",
+           cmd  => fun(#{server := Server} = _State) ->
+                           Server ! {continue, self()},
+                           ok
+                   end},
+
+         %% *** Activate client ***
+         #{desc => "start client",
+           cmd  => fun(#{client := Client, server_port := Port} = _State) ->
+                           Client ! {start, self(), Port},
+                           ok
+                   end},
+         #{desc => "await client ready",
+           cmd  => fun(#{client := Client} = _State) ->
+                           receive
+                               {'DOWN', _, process, Client, Reason} ->
+                                   {error, {unexpected_exit, client, Reason}};
+                               {ready, Client} ->
+                                   ok
+                           end
+                   end},
+
+         %% *** The actual test ***
+         #{desc => "order client to continue (with connect)",
+           cmd  => fun(#{client := Client} = _State) ->
+                           Client ! {continue, self()},
+                           ok
+                   end},
+         #{desc => "await server ready (accept/recv)",
+           cmd  => fun(#{server := Server} = _State) ->
+                           receive
+                               {'DOWN', _, process, Server, Reason} ->
+                                   {error, {unexpected_exit, server, Reason}};
+                               {ready, Server} ->
+                                   ok
+                           end
+                   end},
+
+         %% *** Termination ***
+         #{desc => "order client to terminate",
+           cmd  => fun(#{client := Client} = _State) ->
+                           Client ! {terminate, self()},
+                           ok
+                   end},
+         #{desc => "await client termination",
+           cmd  => fun(#{client := Client} = State) ->
+                           receive
+                               {'DOWN', _, process, Client, _Reason} ->
+                                   State1 = maps:remove(client, State),
+                                   State2 = maps:remove(client_mref, State1),
+                                   {ok, State2}
+                           end
+                   end},
+         #{desc => "order server to terminate",
+           cmd  => fun(#{server := Server} = _State) ->
+                           Server ! {terminate, self()},
+                           ok
+                   end},
+         #{desc => "await server termination",
+           cmd  => fun(#{server := Server} = State) ->
+                           receive
+                               {'DOWN', _, process, Server, _Reason} ->
+                                   State1 = maps:remove(server, State),
+                                   State2 = maps:remove(server_mref, State1),
+                                   State3 = maps:remove(server_port, State2),
+                                   {ok, State3}
+                           end
+                   end},
+
+         %% *** We are done ***
+         #{desc => "finish",
+           cmd  => fun(_) ->
+                           {ok, normal}
+                   end}
+        ],
+
+    
+    i("start server evaluator"),
+    ServerInitState = InitState,
+    #ev{pid = SPid} = Server = evaluator_start("server", 
+                                               ServerSeq, 
+                                               ServerInitState),
+
+    i("start client evaluator"),
+    ClientInitState = InitState,
+    #ev{pid = CPid} = Client = evaluator_start("client", 
+                                               ClientSeq, 
+                                               ClientInitState),
+
+    i("start tester evaluator"),
+    TesterInitState = #{server => SPid, client => CPid},
+    Tester = evaluator_start("tester", TesterSeq, TesterInitState),
+
+    i("await evaluator(s)"),
+    ok = await_evaluator_finish([Server, Client, Tester]).
+
+
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+%% This test case is intended to test the recvfrom timeout option
+%% on an IPv4 UDP (dgram) socket.
+api_to_recvfrom_udp4(suite) ->
+    [];
+api_to_recvfrom_udp4(doc) ->
+    [];
+api_to_recvfrom_udp4(_Config) when is_list(_Config) ->
+    tc_try(api_to_recvfrom_udp4,
+           fun() ->
+                   ?TT(?SECS(10)),
+                   Recv = fun(Sock, To) -> socket:recvfrom(Sock, 0, To) end,
+                   InitState = #{domain  => inet,
+                                 recv    => Recv,
+                                 timeout => 5000},
+                   ok = api_to_receive_udp(InitState)
+           end).
+
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+%% This test case is intended to test the recvfrom timeout option
+%% on an IPv6 UDP (dgram) socket.
+api_to_recvfrom_udp6(suite) ->
+    [];
+api_to_recvfrom_udp6(doc) ->
+    [];
+api_to_recvfrom_udp6(_Config) when is_list(_Config) ->
+    tc_try(api_to_recvfrom_udp6,
+           fun() ->
+                   not_yet_implemented(),
+                   ?TT(?SECS(10)),
+                   Recv = fun(Sock, To) -> socket:recvfrom(Sock, 0, To) end,
+                   InitState = #{domain  => inet6,
+                                 recv    => Recv,
+                                 timeout => 5000},
+                   ok = api_to_receive_udp(InitState)
+           end).
+
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+api_to_receive_udp(InitState) ->
+    TesterSeq =
+        [
+         %% *** Init part ***
+         #{desc => "which local address",
+           cmd  => fun(#{domain := Domain} = State) ->
+                           LAddr = which_local_addr(Domain),
+                           LSA   = #{family => Domain, addr => LAddr},
+                           {ok, State#{lsa => LSA}}
+                   end},
+         #{desc => "create socket",
+           cmd  => fun(#{domain := Domain} = State) ->
+                           case socket:open(Domain, dgram, udp) of
+                               {ok, Sock} ->
+                                   {ok, State#{sock => Sock}};
+                               {error, _} = ERROR ->
+                                   ERROR
+                           end
+                   end},
+         #{desc => "bind to local address",
+           cmd  => fun(#{sock := Sock, lsa := LSA} = _State) ->
+                           case socket:bind(Sock, LSA) of
+                               {ok, _Port} ->
+                                   ok;
+                               {error, _} = ERROR ->
+                                   ERROR
+                           end
+                   end},
+
+         %% *** The actual test ***
+         #{desc => "attempt to read (without success)",
+           cmd  => fun(#{sock := Sock, recv := Recv, timeout := To} = State) ->
+                           Start = t(),
+                           case Recv(Sock, To) of
+                               {error, timeout} ->
+                                   {ok, State#{start => Start, stop => t()}};
+                               {ok, _} ->
+                                   {error, unexpected_sucsess};
+                               {error, _} = ERROR ->
+                                   ERROR
+                           end
+                   end},
+         #{desc => "validate timeout time",
+           cmd  => fun(#{start := Start, stop := Stop, timeout := To} = _State) ->
+                           TDiff  = tdiff(Start, Stop),
+                           if
+                               (TDiff >= To) ->
+                                   ok;
+                               true ->
+                                   {error, {unexpected_timeout, TDiff, To}}
+                           end
+                   end},
+         
+         %% *** Termination ***
+         #{desc => "close socket",
+           cmd  => fun(#{sock := Sock} = _State) ->
+                           sock_close(Sock),
+                           ok
+                   end},
+
+         %% *** We are done ***
+         #{desc => "finish",
+           cmd  => fun(_) ->
+                           {ok, normal}
+                   end}
+        ],
+
+    i("start tester evaluator"),
+    Tester = evaluator_start("tester", TesterSeq, InitState),
+    
+    i("await evaluator"),
+    ok = await_evaluator_finish([Tester]).
+
+
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+%% This test case is intended to test the recvmsg timeout option
+%% on an IPv4 UDP (dgram) socket.
+api_to_recvmsg_udp4(suite) ->
+    [];
+api_to_recvmsg_udp4(doc) ->
+    [];
+api_to_recvmsg_udp4(_Config) when is_list(_Config) ->
+    tc_try(api_to_recvmsg_udp4,
+           fun() ->
+                   ?TT(?SECS(10)),
+                   Recv = fun(Sock, To) -> socket:recvmsg(Sock, To) end,
+                   InitState = #{domain  => inet,
+                                 recv    => Recv,
+                                 timeout => 5000},
+                   ok = api_to_receive_udp(InitState)
+           end).
+
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+%% This test case is intended to test the recvmsg timeout option
+%% on an IPv6 UDP (dgram) socket.
+api_to_recvmsg_udp6(suite) ->
+    [];
+api_to_recvmsg_udp6(doc) ->
+    [];
+api_to_recvmsg_udp6(_Config) when is_list(_Config) ->
+    tc_try(api_to_recvmsg_udp6,
+           fun() ->
+                   not_yet_implemented(),
+                   ?TT(?SECS(10)),
+                   Recv = fun(Sock, To) -> socket:recvmsg(Sock, To) end,
+                   InitState = #{domain  => inet6,
+                                 recv    => Recv,
+                                 timeout => 5000},
+                   ok = api_to_receive_udp(InitState)
+           end).
+
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+%% This test case is intended to test the recvmsg timeout option
+%% on an IPv4 TCP (stream) socket.
+api_to_recvmsg_tcp4(suite) ->
+    [];
+api_to_recvmsg_tcp4(doc) ->
+    [];
+api_to_recvmsg_tcp4(_Config) when is_list(_Config) ->
+    tc_try(api_to_recvmsg_tcp4,
+           fun() ->
+                   ?TT(?SECS(10)),
+                   Recv = fun(Sock, To) -> socket:recvmsg(Sock, To) end,
+                   InitState = #{domain  => inet,
+                                 recv    => Recv,
+                                 timeout => 5000},
+                   ok = api_to_receive_tcp(InitState)
+           end).
+
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+%% This test case is intended to test the recvmsg timeout option
+%% on an IPv6 TCP (stream) socket.
+api_to_recvmsg_tcp6(suite) ->
+    [];
+api_to_recvmsg_tcp6(doc) ->
+    [];
+api_to_recvmsg_tcp6(_Config) when is_list(_Config) ->
+    tc_try(api_to_recvmsg_tcp6,
+           fun() ->
+                   not_yet_implemented(),
+                   ?TT(?SECS(10)),
+                   Recv = fun(Sock, To) -> socket:recvmsg(Sock, To) end,
+                   InitState = #{domain  => inet6,
+                                 recv    => Recv,
+                                 timeout => 5000},
+                   ok = api_to_receive_tcp(InitState)
+           end).
+
+
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%%                                                                     %%
+%%                         SOCKET CLOSURE                              %%
+%%                                                                     %%
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%% This test case is intended to test that the sockets are cleaned up
+%% ("removed") when the controlling process terminates (without explicitly 
+%% calling the close function). For a IPv4 TCP (stream) socket.
+
+sc_cpe_socket_cleanup_tcp4(suite) ->
+    [];
+sc_cpe_socket_cleanup_tcp4(doc) ->
+    [];
+sc_cpe_socket_cleanup_tcp4(_Config) when is_list(_Config) ->
+    tc_try(sc_cpe_socket_cleanup_tcp4,
+           fun() ->
+                   %% not_yet_implemented(),
+                   ?TT(?SECS(5)),
+                   InitState = #{domain   => inet,
+                                 type     => stream,
+                                 protocol => tcp},
+                   ok = sc_cpe_socket_cleanup(InitState)
+           end).
+
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%% This test case is intended to test that the sockets are cleaned up
+%% ("removed") when the controlling process terminates (without explicitly 
+%% calling the close function). For a IPv6 TCP (stream) socket.
+
+sc_cpe_socket_cleanup_tcp6(suite) ->
+    [];
+sc_cpe_socket_cleanup_tcp6(doc) ->
+    [];
+sc_cpe_socket_cleanup_tcp6(_Config) when is_list(_Config) ->
+    tc_try(sc_cpe_socket_cleanup_tcp6,
+           fun() ->
+                   not_yet_implemented(),
+                   ?TT(?SECS(5)),
+                   InitState = #{domain   => inet6,
+                                 type     => stream,
+                                 protocol => tcp},
+                   ok = sc_cpe_socket_cleanup(InitState)
+           end).
+
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%% This test case is intended to test that the sockets are cleaned up
+%% ("removed") when the controlling process terminates (without explicitly 
+%% calling the close function). For a IPv4 UDP (dgram) socket.
+
+sc_cpe_socket_cleanup_udp4(suite) ->
+    [];
+sc_cpe_socket_cleanup_udp4(doc) ->
+    [];
+sc_cpe_socket_cleanup_udp4(_Config) when is_list(_Config) ->
+    tc_try(sc_cpe_socket_cleanup_udp4,
+           fun() ->
+                   ?TT(?SECS(5)),
+                   InitState = #{domain   => inet,
+                                 type     => dgram,
+                                 protocol => udp},
+                   ok = sc_cpe_socket_cleanup(InitState)
+           end).
+
+
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%% This test case is intended to test that the sockets are cleaned up
+%% (removed) when the controlling process terminates (without explicitly 
+%% calling the close function). For a IPv6 UDP (dgram) socket.
+
+sc_cpe_socket_cleanup_udp6(suite) ->
+    [];
+sc_cpe_socket_cleanup_udp6(doc) ->
+    [];
+sc_cpe_socket_cleanup_udp6(_Config) when is_list(_Config) ->
+    tc_try(sc_cpe_socket_cleanup_udp6,
+           fun() ->
+                   not_yet_implemented(),
+                   ?TT(?SECS(5)),
+                   InitState = #{domain   => inet6,
+                                 type     => dgram,
+                                 protocol => udp},
+                   ok = sc_cpe_socket_cleanup(InitState)
+           end).
+
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+sc_cpe_socket_cleanup(InitState) ->
+    OwnerSeq =
+        [
+         %% *** Wait for start order part ***
+         #{desc => "await start (from tester)",
+           cmd  => fun(State) ->
+                           receive
+                               {start, Tester} when is_pid(Tester) ->
+                                   {ok, State#{tester => Tester}}
+                           end
+                   end},
+
+         %% *** Init part ***
+         #{desc => "monitor tester",
+           cmd  => fun(#{tester := Tester} = _State) ->
+                           _MRef = erlang:monitor(process, Tester),
+                           ok
+                   end},
+         #{desc => "create socket",
+           cmd  => fun(#{domain   := Domain, 
+                         type     := Type, 
+                         protocol := Proto} = State) ->
+                           case socket:open(Domain, Type, Proto) of
+                               {ok, Sock} ->
+                                   {ok, State#{sock => Sock}};
+                               {error, _} = ERROR ->
+                                   ERROR
+                           end
+                   end},
+         #{desc => "announce ready",
+           cmd  => fun(#{tester := Tester, sock := Sock} = _State) ->
+                           Tester ! {ready, self(), Sock},
+                           ok
+                   end},
+
+         %% *** The actual test ***
+         %% We intentially leave the socket "as is", no explicit close
+         #{desc => "await terminate (from tester)",
+           cmd  => fun(#{tester := Tester} = State) ->
+                           receive
+                               {'DOWN', _, process, Tester, Reason} ->
+                                   ee("Unexpected DOWN regarding tester ~p: "
+                                      "~n   ~p", [Reason]),
+                                   {error, {unexpected_exit, tester}};
+                               {terminate, Tester} ->
+                                   {ok, maps:remove(tester, State)}
+                           end
+                   end},
+         %% #{desc => "enable (otp) debug",
+         %%   cmd  => fun(#{sock := Sock} = _State) ->
+         %%                   ok = socket:setopt(Sock, otp, debug, true)
+         %%           end},
+
+         %% *** We are done ***
+         #{desc => "finish",
+           cmd  => fun(_) ->
+                           {ok, normal}
+                   end}
+        ],
+
+    TesterSeq =
+        [
+         %% *** Init part ***
+         #{desc => "monitor owner",
+           cmd  => fun(#{owner := Owner} = _State) ->
+                           _MRef = erlang:monitor(process, Owner),
+                           ok
+                   end},
+         #{desc => "order (owner) start",
+           cmd  => fun(#{owner := Pid} = _State) ->
+                           Pid ! {start, self()},
+                           ok
+                   end},
+         #{desc => "await (owner) ready",
+           cmd  => fun(#{owner := Owner} = State) ->
+                           receive
+                               {'DOWN', _, process, Owner, Reason} ->
+                                   ee("Unexpected DOWN regarding owner ~p: "
+                                      "~n   ~p", [Reason]),
+                                   {error, {unexpected_exit, owner}};
+                               {ready, Owner, Sock} ->
+                                   {ok, State#{sock => Sock}}
+                           end
+                   end},
+         #{desc => "verify owner as controlling-process",
+           cmd  => fun(#{owner := Owner, sock := Sock} = _State) ->
+                           case socket:getopt(Sock, otp, controlling_process) of
+                               {ok, Owner} ->
+                                   ok;
+                               {ok, Other} ->
+                                   {error, {unexpected_owner, Other}};
+                               {error, _} = ERROR ->
+                                   ERROR
+                           end
+                   end},
+         #{desc => "order (owner) terminate",
+           cmd  => fun(#{owner := Pid} = _State) ->
+                           Pid ! {terminate, self()},
+                           ok
+                   end},
+         #{desc => "await (owner) termination",
+           cmd  => fun(#{owner := Owner} = _State) ->
+                           receive
+                               {'DOWN', _, process, Owner, _} ->
+                                   ok
+                           end
+                   end},
+         #{desc => "verify no socket (closed)",
+           cmd  => fun(#{owner := Owner, sock := Sock} = _State) ->
+                           case socket:getopt(Sock, otp, controlling_process) of
+                               {ok, Pid} ->
+                                   {error, {unexpected_success, Owner, Pid}};
+                               {error, closed} ->
+                                   ok;
+                               {error, Reason} ->
+                                   ei("expected failure: ~p", [Reason]),
+                                   {error, {unexpected_failure, Reason}}
+                           end
+                   end},
+
+         %% *** We are done ***
+         #{desc => "finish",
+           cmd  => fun(_) ->
+                           {ok, normal}
+                   end}
+        ],
+
+    i("start (socket) owner evaluator"),
+    #ev{pid = Pid} = Owner = evaluator_start("owner", OwnerSeq, InitState),
+
+    i("start tester evaluator"),
+    TesterInitState = #{owner => Pid},
+    Tester = evaluator_start("tester", TesterSeq, TesterInitState),
+
+    i("await evaluator"),
+    ok = await_evaluator_finish([Owner, Tester]).
+
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%% This test case is intended to test what happens when a socket is 
+%% locally closed while a process is calling the recv function.
+%% Socket is IPv4.
+%% 
+%% <KOLLA>
+%% 
+%% We should really have a similar test cases for when the controlling
+%% process exits and there are other processes in recv, accept, and 
+%% all the other functions.
+%% 
+%% </KOLLA>
+
+sc_lc_recv_response_tcp4(suite) ->
+    [];
+sc_lc_recv_response_tcp4(doc) ->
+    [];
+sc_lc_recv_response_tcp4(_Config) when is_list(_Config) ->
+    tc_try(sc_lc_recv_response_tcp4,
+           fun() ->
+                   ?TT(?SECS(10)),
+                   Recv      = fun(Sock) -> socket:recv(Sock) end,
+                   InitState = #{domain   => inet,
+                                 type     => stream,
+                                 protocol => tcp,
+                                 recv     => Recv},
+                   ok = sc_lc_receive_response_tcp(InitState)
+           end).
+
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%% This test case is intended to test what happens when a socket is 
+%% locally closed while the process is calling the recv function.
+%% Socket is IPv6.
+
+sc_lc_recv_response_tcp6(suite) ->
+    [];
+sc_lc_recv_response_tcp6(doc) ->
+    [];
+sc_lc_recv_response_tcp6(_Config) when is_list(_Config) ->
+    tc_try(sc_lc_recv_response_tcp6,
+           fun() ->
+                   not_yet_implemented(),
+                   ?TT(?SECS(10)),
+                   Recv      = fun(Sock) -> socket:recv(Sock) end,
+                   InitState = #{domain   => inet6,
+                                 type     => stream,
+                                 protocol => tcp,
+                                 recv     => Recv},
+                   ok = sc_lc_receive_response_tcp(InitState)
+           end).
+
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+sc_lc_receive_response_tcp(InitState) ->
+    %% This is the server that accepts connections.
+    %% But it is also suppose to close the connection socket, 
+    %% and trigger the read failure for the handler process.
+    AcceptorSeq =
+        [
+         %% *** Wait for start order part ***
+         #{desc => "await start (from tester)",
+           cmd  => fun(State) ->
+                           receive
+                               {start, Tester} when is_pid(Tester) ->
+                                   {ok, State#{tester => Tester}}
+                           end
+                   end},
+         #{desc => "monitor tester",
+           cmd  => fun(#{tester := Tester} = _State) ->
+                           _MRef = erlang:monitor(process, Tester),
+                           ok
+                   end},
+
+         %% *** Init part ***
+         #{desc => "which local address",
+           cmd  => fun(#{domain := Domain} = State) ->
+                           LAddr = which_local_addr(Domain),
+                           LSA   = #{family => Domain, addr => LAddr},
+                           {ok, State#{lsa => LSA}}
+                   end},
+         #{desc => "create (listen) socket",
+           cmd  => fun(#{domain   := Domain, 
+                         type     := Type, 
+                         protocol := Proto} = State) ->
+                           case socket:open(Domain, Type, Proto) of
+                               {ok, Sock} ->
+                                   {ok, State#{lsock => Sock}};
+                               {error, _} = ERROR ->
+                                   ERROR
+                           end
+                   end},
+         #{desc => "bind to local address",
+           cmd  => fun(#{lsock := LSock, lsa := LSA} = State) ->
+                           case socket:bind(LSock, LSA) of
+                               {ok, Port} ->
+                                   {ok, State#{lport => Port}};
+                               {error, _} = ERROR ->
+                                   ERROR
+                           end
+                   end},
+         #{desc => "make listen socket",
+           cmd  => fun(#{lsock := LSock}) ->
+                           socket:listen(LSock)
+                   end},
+         #{desc => "announce ready (init)",
+           cmd  => fun(#{tester := Tester, lport := Port}) ->
+                           Tester ! {ready, self(), Port},
+                           ok
+                   end},
+                           
+         %% The actual test
+         #{desc => "await continue (connection)",
+           cmd  => fun(#{tester := Tester} = State) ->
+                           receive
+                               {'DOWN', _, process, Tester, Reason} ->
+                                   ee("Unexpected DOWN regarding tester ~p: "
+                                      "~n   ~p", [Reason]),
+                                   {error, {unexpected_exit, tester}};
+                               {continue, Tester, Handler} ->
+                                   {ok, State#{handler => Handler}}
+                           end
+                   end},
+         #{desc => "await connection",
+           cmd  => fun(#{lsock := LSock} = State) ->
+                           case socket:accept(LSock) of
+                               {ok, Sock} ->
+                                   ei("connection accepted"),
+                                   {ok, State#{csock => Sock}};
+                               {error, _} = ERROR ->
+                                   ERROR
+                           end
+                   end},
+         #{desc => "transfer new connection to handler",
+           cmd  => fun(#{handler := Handler, csock := Sock}) ->
+                           ok = socket:setopt(Sock, 
+                                              otp, controlling_process, 
+                                              Handler),
+                           Handler ! {connection, Sock},
+                           ok
+                   end},
+         #{desc => "announce ready (connection)",
+           cmd  => fun(#{tester := Tester}) ->
+                           Tester ! {ready, self()},
+                           ok
+                   end},
+         #{desc => "await continue (close)",
+           cmd  => fun(#{tester := Tester} = _State) ->
+                           receive
+                               {'DOWN', _, process, Tester, Reason} ->
+                                   ee("Unexpected DOWN regarding tester ~p: "
+                                      "~n   ~p", [Reason]),
+                                   {error, {unexpected_exit, tester}};
+                               {continue, Tester} ->
+                                   ok
+                           end
+                   end},
+         %% #{desc => "enable debug",
+         %%   cmd  => fun(#{csock := Sock}) ->
+         %%                   socket:setopt(Sock, otp, debug, true)
+         %%           end},
+         #{desc => "close (the connection) socket",
+           cmd  => fun(#{csock := Sock}) ->
+                           socket:close(Sock)
+                   end},
+
+         #{desc => "await terminate",
+           cmd  => fun(#{tester := Tester} = State) ->
+                           receive
+                               {'DOWN', _, process, Tester, Reason} ->
+                                   ee("Unexpected DOWN regarding tester ~p: "
+                                      "~n   ~p", [Reason]),
+                                   {error, {unexpected_exit, tester}};
+                               {terminate, Tester} ->
+                                   {ok, maps:remove(tester, State)}
+                           end
+                   end},
+         #{desc => "socket cleanup",
+           cmd  => fun(#{lsock := Sock} = State) ->
+                           ok = socket:close(Sock),
+                           State1 = maps:remove(csock, State),
+                           State2 = maps:remove(lsock, State1),
+                           State3 = maps:remove(lport, State2),
+                           {ok, State3}
+                   end},
+
+         %% *** We are done ***
+         #{desc => "finish",
+           cmd  => fun(_) ->
+                           {ok, normal}
+                   end}
+        ],
+
+    %% The point of this is to perform the recv for which we are testing the reponse
+    HandlerSeq =
+        [
+         %% *** Wait for start order part ***
+         #{desc => "await start (from tester)",
+           cmd  => fun(State) ->
+                           receive
+                               {start, Tester} when is_pid(Tester) ->
+                                   {ok, State#{tester => Tester}}
+                           end
+                   end},
+         #{desc => "monitor server",
+           cmd  => fun(#{tester := Tester} = _State) ->
+                           _MRef = erlang:monitor(process, Tester),
+                           ok
+                   end},
+         #{desc => "announce ready (init)",
+           cmd  => fun(#{tester := Tester}) ->
+                           Tester ! {ready, self()},
+                           ok
+                   end},
+
+         %% The actual test
+         #{desc => "await connection socket",
+           cmd  => fun(#{tester := Tester} = State) ->
+                           receive
+                               {'DOWN', _, process, Tester, Reason} ->
+                                   ee("Unexpected DOWN regarding tester ~p: "
+                                      "~n   ~p", [Reason]),
+                                   {error, {unexpected_exit, tester}};
+                               {connection, Sock} ->
+                                   {ok, State#{sock => Sock}}
+                           end
+                   end},
+         #{desc => "announce ready (connection)",
+           cmd  => fun(#{tester := Tester}) ->
+                           Tester ! {ready, self()},
+                           ok
+                   end},
+         %% #{desc => "enable debug",
+         %%   cmd  => fun(#{sock := Sock}) ->
+         %%                   socket:setopt(Sock, otp, debug, true)
+         %%           end},
+         %% #{desc => "monitored-by",
+         %%   cmd  => fun(_) ->
+         %%                   {_, Mons} = process_info(self(), monitored_by),
+         %%                   ei("Monitored By: ~p", [Mons]),
+         %%                   ok
+         %%           end},
+         #{desc => "attempt recv",
+           cmd  => fun(#{sock := Sock, recv := Recv} = State) ->
+                           case Recv(Sock) of
+                               {ok, _Data} ->
+                                   ee("Unexpected data received"),
+                                   {error, unexpected_data};
+                               {error, closed} ->
+                                   State1 = maps:remove(sock, State),
+                                   {ok, State1};
+                               {error, Reason} = ERROR ->
+                                   ee("Unexpected read faulure: "
+                                      "~n   ~p", [Reason]),
+                                   ERROR
+                           end
+                   end},
+         %% #{desc => "monitored-by",
+         %%   cmd  => fun(_) ->
+         %%                   {_, Mons} = process_info(self(), monitored_by),
+         %%                   ei("Monitored By: ~p", [Mons]),
+         %%                   ok
+         %%           end},
+         #{desc => "announce ready (close)",
+           cmd  => fun(#{tester := Tester}) ->
+                           Tester ! {ready, self()},
+                           ok
+                   end},
+         #{desc => "sleep some",
+           cmd  => fun(_) ->
+                           ?SLEEP(1000),
+                           ok
+                   end},
+         %% #{desc => "monitored-by",
+         %%   cmd  => fun(_) ->
+         %%                   {_, Mons} = process_info(self(), monitored_by),
+         %%                   ei("Monitored By: ~p", [Mons]),
+         %%                   ok
+         %%           end},
+         #{desc => "await terminate",
+           cmd  => fun(#{tester := Tester} = _State) ->
+                           receive
+                               {'DOWN', _, process, Tester, Reason} ->
+                                   ee("Unexpected DOWN regarding tester ~p: "
+                                      "~n   ~p", [Reason]),
+                                   {error, {unexpected_exit, tester}};
+                               {terminate, Tester} ->
+                                   ok
+                           end
+                   end},
+
+
+         %% *** We are done ***
+         #{desc => "finish",
+           cmd  => fun(_) ->
+                           {ok, normal}
+                   end}
+        ],
+
+    %% The point of this is basically just to create the connection.
+    ClientSeq =
+        [
+         %% *** Wait for start order part ***
+         #{desc => "await start (from tester)",
+           cmd  => fun(State) ->
+                           receive
+                               {start, Tester} when is_pid(Tester) ->
+                                   {ok, State#{tester => Tester}}
+                           end
+                   end},
+
+         %% Init
+         #{desc => "which local address",
+           cmd  => fun(#{domain := Domain} = State) ->
+                           LAddr = which_local_addr(Domain),
+                           LSA   = #{family => Domain, addr => LAddr},
+                           {ok, State#{lsa => LSA}}
+                   end},
+         #{desc => "create socket",
+           cmd  => fun(#{domain   := Domain, 
+                         type     := Type, 
+                         protocol := Proto} = State) ->
+                           case socket:open(Domain, Type, Proto) of
+                               {ok, Sock} ->
+                                   {ok, State#{sock => Sock}};
+                               {error, _} = ERROR ->
+                                   ERROR
+                           end
+                   end},
+         #{desc => "bind socket to local address",
+           cmd  => fun(#{sock := Sock, lsa := LSA} = _State) ->
+                           case socket:bind(Sock, LSA) of
+                               {ok, _} ->
+                                   ok;
+                               {error, _} = ERROR ->
+                                   ERROR
+                           end
+                   end},
+         #{desc => "announce ready",
+           cmd  => fun(#{tester := Tester} = _State) ->
+                           Tester ! {ready, self()},
+                           ok
+                   end},
+
+         %% The actual test
+         #{desc => "await continue",
+           cmd  => fun(#{tester := Tester} = State) ->
+                           receive
+                               {'DOWN', _, process, Tester, Reason} ->
+                                   ee("Unexpected DOWN regarding tester ~p: "
+                                      "~n   ~p", [Tester, Reason]),
+                                   {error, {unexpected_exit, tester, Reason}};
+                               {continue, Tester, Port} ->
+                                   {ok, State#{lport => Port}}
+                           end
+                   end},
+         #{desc => "connect to server",
+           cmd  => fun(#{sock := Sock, lsa := LSA, lport := LPort}) ->
+                           socket:connect(Sock, LSA#{port => LPort})
+                   end},
+         #{desc => "announce ready (connection)",
+           cmd  => fun(#{tester := Tester} = _State) ->
+                           Tester ! {ready, self()},
+                           ok
+                   end},
+
+         %% Cleaning up
+         #{desc => "await terminate (from tester)",
+           cmd  => fun(#{tester := Tester} = State) ->
+                           receive
+                               {'DOWN', _, process, Tester, Reason} ->
+                                   ee("Unexpected DOWN regarding tester ~p: "
+                                      "~n   ~p", [Tester, Reason]),
+                                   {error, {unexpected_exit, tester}};
+                               {terminate, Tester} ->
+                                   {ok, maps:remove(tester, State)}
+                           end
+                   end},
+         #{desc => "close socket",
+           cmd  => fun(#{sock := Sock} = State) ->
+                           sock_close(Sock),
+                           {ok, maps:remove(sock, State)}
+                   end},
+
+         %% *** We are done ***
+         #{desc => "finish",
+           cmd  => fun(_) ->
+                           {ok, normal}
+                   end}
+        ],
+
+    TesterSeq =
+        [
+         %% *** Init part ***
+         #{desc => "monitor acceptor",
+           cmd  => fun(#{acceptor := Pid} = _State) ->
+                           _MRef = erlang:monitor(process, Pid),
+                           ok
+                   end},
+         #{desc => "monitor handler",
+           cmd  => fun(#{handler := Pid} = _State) ->
+                           _MRef = erlang:monitor(process, Pid),
+                           ok
+                   end},
+         #{desc => "monitor client",
+           cmd  => fun(#{client := Pid} = _State) ->
+                           _MRef = erlang:monitor(process, Pid),
+                           ok
+                   end},
+
+         %% Start the acceptor
+         #{desc => "order acceptor start",
+           cmd  => fun(#{acceptor := Pid} = _State) ->
+                           Pid ! {start, self()},
+                           ok
+                   end},
+         #{desc => "await acceptor ready (init)",
+           cmd  => fun(#{acceptor := Pid} = State) ->
+                           receive
+                               {'DOWN', _, process, Pid, Reason} ->
+                                   ee("Unexpected DOWN regarding acceptor ~p: "
+                                      "~n   ~p", [Pid, Reason]),
+                                   {error, {unexpected_exit, acceptor}};
+                               {ready, Pid, Port} ->
+                                   {ok, State#{lport => Port}}
+                           end
+                   end},
+
+         %% Start the handler
+         #{desc => "order handler start",
+           cmd  => fun(#{handler := Pid} = _State) ->
+                           Pid ! {start, self()},
+                           ok
+                   end},
+         #{desc => "await handler ready (init)",
+           cmd  => fun(#{handler := Pid} = _State) ->
+                           receive
+                               {'DOWN', _, process, Pid, Reason} ->
+                                   ee("Unexpected DOWN regarding handler ~p: "
+                                      "~n   ~p", [Pid, Reason]),
+                                   {error, {unexpected_exit, acceptor}};
+                               {ready, Pid} ->
+                                   ok
+                           end
+                   end},
+
+         %% Start the client
+         #{desc => "order client start",
+           cmd  => fun(#{client := Pid} = _State) ->
+                           Pid ! {start, self()},
+                           ok
+                   end},
+         #{desc => "await client ready (init)",
+           cmd  => fun(#{client := Pid} = _State) ->
+                           receive
+                               {'DOWN', _, process, Pid, Reason} ->
+                                   ee("Unexpected DOWN regarding cient ~p: "
+                                      "~n   ~p", [Pid, Reason]),
+                                   {error, {unexpected_exit, acceptor}};
+                               {ready, Pid} ->
+                                   ok
+                           end
+                   end},
+
+         %% The actual test
+         #{desc => "order acceptor to continue",
+           cmd  => fun(#{acceptor := Pid, handler := Handler} = _State) ->
+                           Pid ! {continue, self(), Handler},
+                           ok
+                   end},
+         #{desc => "order client to continue",
+           cmd  => fun(#{client := Pid, lport := Port} = _State) ->
+                           Pid ! {continue, self(), Port},
+                           ok
+                   end},
+         #{desc => "await acceptor ready (connection)",
+           cmd  => fun(#{acceptor := Pid} = _State) ->
+                           receive
+                               {'DOWN', _, process, Pid, Reason} ->
+                                   ee("Unexpected DOWN regarding acceptor ~p: "
+                                      "~n   ~p", [Pid, Reason]),
+                                   {error, {unexpected_exit, acceptor}};
+                               {ready, Pid} ->
+                                   ok
+                           end
+                   end},
+         #{desc => "await client ready (connection)",
+           cmd  => fun(#{client := Pid} = _State) ->
+                           receive
+                               {'DOWN', _, process, Pid, Reason} ->
+                                   ee("Unexpected DOWN regarding client ~p: "
+                                      "~n   ~p", [Pid, Reason]),
+                                   {error, {unexpected_exit, acceptor}};
+                               {ready, Pid} ->
+                                   ok
+                           end
+                   end},
+         #{desc => "await handler ready (connection)",
+           cmd  => fun(#{handler := Pid} = _State) ->
+                           receive
+                               {'DOWN', _, process, Pid, Reason} ->
+                                   ee("Unexpected DOWN regarding handler ~p: "
+                                      "~n   ~p", [Reason]),
+                                   {error, {unexpected_exit, acceptor}};
+                               {ready, Pid} ->
+                                   ok
+                           end
+                   end},
+         #{desc => "sleep some",
+           cmd  => fun(_State) ->
+                           ?SLEEP(1000),
+                           ok
+                   end},
+         #{desc => "order acceptor to continue (close)",
+           cmd  => fun(#{acceptor := Pid} = _State) ->
+                           Pid ! {continue, self()},
+                           ok
+                   end},
+         #{desc => "await handler ready (close)",
+           cmd  => fun(#{handler := Pid} = _State) ->
+                           receive
+                               {'DOWN', _, process, Pid, Reason} ->
+                                   ee("Unexpected DOWN regarding handler ~p: "
+                                      "~n   ~p", [Pid, Reason]),
+                                   {error, {unexpected_exit, acceptor}};
+                               {ready, Pid} ->
+                                   ok
+                           end
+                   end},
+
+         %% Terminations
+         #{desc => "order handler to terminate",
+           cmd  => fun(#{handler := Pid} = _State) ->
+                           Pid ! {terminate, self()},
+                           ok
+                   end},
+         #{desc => "await handler termination",
+           cmd  => fun(#{handler := Pid} = State) ->
+                           receive
+                               {'DOWN', _, process, Pid, _} ->
+                                   {ok, maps:remove(handler, State)}
+                           end
+                   end},
+         #{desc => "order client to terminate",
+           cmd  => fun(#{client := Pid} = _State) ->
+                           Pid ! {terminate, self()},
+                           ok
+                   end},
+         #{desc => "await client termination",
+           cmd  => fun(#{client := Pid} = State) ->
+                           receive
+                               {'DOWN', _, process, Pid, _} ->
+                                   {ok, maps:remove(client, State)}
+                           end
+                   end},
+         #{desc => "order acceptor to terminate",
+           cmd  => fun(#{acceptor := Pid} = _State) ->
+                           Pid ! {terminate, self()},
+                           ok
+                   end},
+         #{desc => "await acceptor termination",
+           cmd  => fun(#{acceptor := Pid} = State) ->
+                           receive
+                               {'DOWN', _, process, Pid, _} ->
+                                   {ok, maps:remove(acceptor, State)}
+                           end
+                   end},
+
+
+         %% *** We are done ***
+         #{desc => "finish",
+           cmd  => fun(_) ->
+                           {ok, normal}
+                   end}
+        ],
+
+    i("start acceptor evaluator"),
+    AccInitState = InitState,
+    #ev{pid = APid} = Acceptor = evaluator_start("acceptor", 
+                                                 AcceptorSeq, 
+                                                 AccInitState),
+
+    i("start handler evaluator"),
+    HandlerInitState = #{recv => maps:get(recv, InitState)},
+    #ev{pid = HPid} = Handler = evaluator_start("handler", 
+                                                HandlerSeq, 
+                                                HandlerInitState),
+
+    i("start client evaluator"),
+    ClientInitState = InitState,
+    #ev{pid = CPid} = Client = evaluator_start("client", 
+                                               ClientSeq, 
+                                               ClientInitState),
+
+    i("start tester evaluator"),
+    TesterInitState = #{acceptor => APid,
+                        handler  => HPid,
+                        client   => CPid},
+    Tester = evaluator_start("tester", TesterSeq, TesterInitState),
+
+    i("await evaluator"),
+    ok = await_evaluator_finish([Acceptor, Handler, Client, Tester]).
+
+
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%% This test case is intended to test what happens when a socket is 
+%% remotely closed while the process is calling the recv function.
+%% Socket is IPv4.
+
+sc_rc_recv_response_tcp4(suite) ->
+    [];
+sc_rc_recv_response_tcp4(doc) ->
+    [];
+sc_rc_recv_response_tcp4(_Config) when is_list(_Config) ->
+    tc_try(sc_rc_recv_response_tcp4,
+           fun() ->
+                   not_yet_implemented(),
+                   ?TT(?SECS(10)),
+                   Recv      = fun(Sock) -> socket:recv(Sock) end,
+                   InitState = #{domain   => inet,
+                                 type     => stream,
+                                 protocol => tcp,
+                                 recv     => Recv},
+                   ok = sc_rc_receive_response_tcp(InitState)
+           end).
+
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%% This test case is intended to test what happens when a socket is 
+%% remotely closed while the process is calling the recv function.
+%% Socket is IPv6.
+
+sc_rc_recv_response_tcp6(suite) ->
+    [];
+sc_rc_recv_response_tcp6(doc) ->
+    [];
+sc_rc_recv_response_tcp6(_Config) when is_list(_Config) ->
+    tc_try(sc_rc_recv_response_tcp6,
+           fun() ->
+                   not_yet_implemented(),
+                   ?TT(?SECS(10)),
+                   Recv      = fun(Sock) -> socket:recv(Sock) end,
+                   InitState = #{domain   => inet6,
+                                 type     => stream,
+                                 protocol => tcp,
+                                 recv     => Recv},
+                   ok = sc_rc_receive_response_tcp(InitState)
+           end).
+
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+sc_rc_receive_response_tcp(_InitState) ->
+    ok.
+
+
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%% This test case is intended to test what happens when a socket is 
+%% locally closed while the process is calling the recvmsg function.
+%% Socket is IPv4.
+
+sc_lc_recvmsg_response_tcp4(suite) ->
+    [];
+sc_lc_recvmsg_response_tcp4(doc) ->
+    [];
+sc_lc_recvmsg_response_tcp4(_Config) when is_list(_Config) ->
+    tc_try(sc_lc_recvmsg_response_tcp4,
+           fun() ->
+                   ?TT(?SECS(10)),
+                   Recv      = fun(Sock) -> socket:recvmsg(Sock) end,
+                   InitState = #{domain   => inet,
+                                 type     => stream,
+                                 protocol => tcp,
+                                 recv     => Recv},
+                   ok = sc_lc_receive_response_tcp(InitState)
+           end).
+
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%% This test case is intended to test what happens when a socket is 
+%% locally closed while the process is calling the recvmsg function.
+%% Socket is IPv6.
+
+sc_lc_recvmsg_response_tcp6(suite) ->
+    [];
+sc_lc_recvmsg_response_tcp6(doc) ->
+    [];
+sc_lc_recvmsg_response_tcp6(_Config) when is_list(_Config) ->
+    tc_try(sc_recvmsg_response_tcp6,
+           fun() ->
+                   not_yet_implemented(),
+                   ?TT(?SECS(10)),
+                   Recv      = fun(Sock) -> socket:recvmsg(Sock) end,
+                   InitState = #{domain   => inet6,
+                                 type     => stream,
+                                 protocol => tcp,
+                                 recv     => Recv},
+                   ok = sc_lc_receive_response_tcp(InitState)
+           end).
+
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%% This test case is intended to test what happens when a socket is 
+%% remotely closed while the process is calling the recvmsg function.
+%% Socket is IPv4.
+
+sc_rc_recvmsg_response_tcp4(suite) ->
+    [];
+sc_rc_recvmsg_response_tcp4(doc) ->
+    [];
+sc_rc_recvmsg_response_tcp4(_Config) when is_list(_Config) ->
+    tc_try(sc_rc_recvmsg_response_tcp4,
+           fun() ->
+                   not_yet_implemented(),
+                   ?TT(?SECS(10)),
+                   Recv      = fun(Sock) -> socket:recvmsg(Sock) end,
+                   InitState = #{domain   => inet,
+                                 type     => stream,
+                                 protocol => tcp,
+                                 recv     => Recv},
+                   ok = sc_rc_receive_response_tcp(InitState)
+           end).
+
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%% This test case is intended to test what happens when a socket is 
+%% remotely closed while the process is calling the recvmsg function.
+%% Socket is IPv6.
+
+sc_rc_recvmsg_response_tcp6(suite) ->
+    [];
+sc_rc_recvmsg_response_tcp6(doc) ->
+    [];
+sc_rc_recvmsg_response_tcp6(_Config) when is_list(_Config) ->
+    tc_try(sc_rc_recvmsg_response_tcp6,
+           fun() ->
+                   not_yet_implemented(),
+                   ?TT(?SECS(10)),
+                   Recv      = fun(Sock) -> socket:recvmsg(Sock) end,
+                   InitState = #{domain   => inet6,
+                                 type     => stream,
+                                 protocol => tcp,
+                                 recv     => Recv},
+                   ok = sc_rc_receive_response_tcp(InitState)
+           end).
+
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%% This test case is intended to test what happens when a socket is 
+%% locally closed while the process is calling the accept function.
+%% We test what happens with a non-controlling_process also, since we 
+%% git the setup anyway.
+%% Socket is IPv4.
+
+sc_lc_acceptor_response_tcp4(suite) ->
+    [];
+sc_lc_acceptor_response_tcp4(doc) ->
+    [];
+sc_lc_acceptor_response_tcp4(_Config) when is_list(_Config) ->
+    tc_try(sc_lc_acceptor_response_tcp4,
+           fun() ->
+                   not_yet_implemented(),
+                   ?TT(?SECS(10)),
+                   InitState = #{domain   => inet,
+                                 type     => stream,
+                                 protocol => tcp},
+                   ok = sc_lc_acceptor_response_tcp(InitState)
+           end).
+
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%% This test case is intended to test what happens when a socket is 
+%% locally closed while the process is calling the accept function.
+%% We test what happens with a non-controlling_process also, since we 
+%% git the setup anyway.
+%% Socket is IPv6.
+
+sc_lc_acceptor_response_tcp6(suite) ->
+    [];
+sc_lc_acceptor_response_tcp6(doc) ->
+    [];
+sc_lc_acceptor_response_tcp6(_Config) when is_list(_Config) ->
+    tc_try(sc_lc_acceptor_response_tcp6,
+           fun() ->
+                   not_yet_implemented(),
+                   ?TT(?SECS(10)),
+                   InitState = #{domain   => inet,
+                                 type     => stream,
+                                 protocol => tcp},
+                   ok = sc_lc_acceptor_response_tcp(InitState)
+           end).
+
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+sc_lc_acceptor_response_tcp(_InitState) ->
+    ok.
+
+
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+%% This gets the local address (not 127.0...)
+%% We should really implement this using the (new) net module,
+%% but until that gets the necessary functionality...
+which_local_addr(Domain) ->
+    case inet:getifaddrs() of
+        {ok, IFL} ->
+            which_addr(Domain, IFL);
+        {error, Reason} ->
+            ?FAIL({inet, getifaddrs, Reason})
+    end.
+
+which_addr(_Domain, []) ->
+    ?FAIL(no_address);
+which_addr(Domain, [{Name, IFO}|_IFL]) when (Name =/= "lo") ->
+    which_addr2(Domain, IFO);
+which_addr(Domain, [_|IFL]) ->
+    which_addr(Domain, IFL).
+
+which_addr2(_Domain, []) ->
+    ?FAIL(no_address);
+which_addr2(inet = _Domain, [{addr, Addr}|_IFO]) when (size(Addr) =:= 4) ->
+    Addr;
+which_addr2(inet6 = _Domain, [{addr, Addr}|_IFO]) when (size(Addr) =:= 8) ->
+    Addr;
+which_addr2(Domain, [_|IFO]) ->
+    which_addr2(Domain, IFO).
+   
+
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+%% An evaluator is a process that executes a command sequence.
+%% A test case will consist of atleast one evaluator (one for
+%% each actor).
+%% The evaluator process *always* run locally. Which means that
+%% it will act as a "proxy" for remote nodes in necessary.
+%% When the command sequence has been processed, the final state
+%% will be used as exit reason.
+%% A successful command shall evaluate to ok | {ok, NewState} 
+
+-spec evaluator_start(Name, Seq, Init) -> ev() when
+      Name :: string(),
+      Seq  :: [command()],
+      Init :: initial_evaluator_state().
+                             
+evaluator_start(Name, Seq, Init) 
+  when is_list(Name) andalso is_list(Seq) andalso (Seq =/= []) ->
+    Init2 = Init#{parent => self()},
+    {Pid, MRef} = erlang:spawn_monitor(
+                    fun() -> evaluator_init(Name, Seq, Init2) end),
+    ?MKEV(Name, Pid, MRef).
+
+evaluator_init(Name, Seq, Init) ->
+    put(sname, Name),
+    evaluator_loop(1, Seq, Init).
+
+evaluator_loop(_ID, [], FinalState) ->
+    exit(FinalState);
+evaluator_loop(ID, [#{desc := Desc,
+                      cmd  := Cmd}|Cmds], State) when is_function(Cmd, 1) ->
+    ei("evaluate command ~2w: ~s", [ID, Desc]),
+    try Cmd(State) of
+        ok ->
+            evaluator_loop(ID + 1, Cmds, State);
+        {ok, NewState} ->
+            evaluator_loop(ID + 1, Cmds, NewState);
+        {error, Reason} ->
+            ee("command ~w failed: "
+               "~n   Reason: ~p", [ID, Reason]),
+            exit({command_failed, ID, Reason, State})
+    catch
+        C:E:S ->
+            ee("command ~w crashed: "
+               "~n   Class:      ~p"
+               "~n   Error:      ~p"
+               "~n   Call Stack: ~p", [ID, C, E, S]),
+            exit({command_crashed, ID, {C,E,S}, State})
+    end.
+
+await_evaluator_finish(Evs) ->
+    await_evaluator_finish(Evs, []).
+
+await_evaluator_finish([], []) ->
+    ok;
+await_evaluator_finish([], Fails) ->
+    Fails;
+await_evaluator_finish(Evs, Fails) ->
+    receive
+        {'DOWN', _MRef, process, Pid, normal} ->
+            case lists:keysearch(Pid, #ev.pid, Evs) of
+                {value, #ev{name = Name}} ->
+                    i("evaluator '~s' (~p) success", [Name, Pid]),
+                    NewEvs = lists:keydelete(Pid, #ev.pid, Evs),
+                    await_evaluator_finish(NewEvs, Fails);
+                false ->
+                    i("unknown process ~p died (normal)", [Pid]),
+                    await_evaluator_finish(Evs, Fails)
+                end;
+        {'DOWN', _MRef, process, Pid, Reason} ->
+            case lists:keysearch(Pid, #ev.pid, Evs) of
+                {value, #ev{name = Name}} ->
+                    i("evaluator '~s' (~p) failed", [Name, Pid]),
+                    NewEvs = lists:keydelete(Pid, #ev.pid, Evs),
+                    await_evaluator_finish(NewEvs, [{Pid, Reason}|Fails]);
+                false ->
+                    i("unknown process ~p died: "
+                      "~n   ~p", [Pid, Reason]),
+                    await_evaluator_finish(Evs, Fails)
+                end
+    end.
+
+
+ei(F) ->
+    ei(F, []).
+ei(F, A) ->
+    eprint("", F, A).
+
+ee(F) ->
+    ee(F, []).
+ee(F, A) ->
+    eprint("<ERROR> ", F, A).
+
+eprint(Prefix, F, A) ->
+    %% The two prints is to get the output both in the shell (for when
+    %% "personal" testing is going on) and in the logs.
+    FStr = f("[~s][~s][~p] ~s" ++ F, 
+             [formated_timestamp(), get(sname), self(), Prefix | A]),
+    io:format(user, FStr ++ "~n", []),
+    io:format(FStr, []).
+
+
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+sock_open(Domain, Type, Proto) ->
+    try socket:open(Domain, Type, Proto) of
+        {ok, Socket} ->
+            Socket;
+        {error, Reason} ->
+            ?FAIL({open, Reason})
+    catch
+        C:E:S ->
+            ?FAIL({open, C, E, S})
+    end.
+
+
+sock_bind(Sock, SockAddr) ->
+    try socket:bind(Sock, SockAddr) of
+        {ok, Port} ->
+            Port;
+        {error, Reason} ->
+            i("sock_bind -> error: ~p", [Reason]),
+            ?FAIL({bind, Reason})
+    catch
+        C:E:S ->
+            i("sock_bind -> failed: ~p, ~p, ~p", [C, E, S]),
+            ?FAIL({bind, C, E, S})
+    end.
+
+sock_connect(Sock, SockAddr) ->
+    try socket:connect(Sock, SockAddr) of
+        ok ->
+            ok;
+        {error, Reason} ->
+            ?FAIL({connect, Reason})
+    catch
+        C:E:S ->
+            ?FAIL({connect, C, E, S})
+    end.
+    
+sock_sockname(Sock) ->
+    try socket:sockname(Sock) of
+        {ok, SockAddr} ->
+            SockAddr;
+        {error, Reason} ->
+            ?FAIL({sockname, Reason})
+    catch
+        C:E:S ->
+            ?FAIL({sockname, C, E, S})
+    end.
+    
+
+%% sock_listen(Sock) ->
+%%     sock_listen2(fun() -> socket:listen(Sock) end).
+
+%% sock_listen(Sock, BackLog) ->
+%%     sock_listen2(fun() -> socket:listen(Sock, BackLog) end).
+
+%% sock_listen2(Listen) ->
+%%     try Listen() of
+%%         ok ->
+%%             ok;
+%%         {error, Reason} ->
+%%             ?FAIL({listen, Reason})
+%%     catch
+%%         C:E:S ->
+%%             ?FAIL({listen, C, E, S})
+%%     end.
+
+
+%% sock_accept(LSock) ->
+%%     try socket:accept(LSock) of
+%%         {ok, Sock} ->
+%%             Sock;
+%%         {error, Reason} ->
+%%             i("sock_accept -> error: ~p", [Reason]),
+%%             ?FAIL({accept, Reason})
+%%     catch
+%%         C:E:S ->
+%%             i("sock_accept -> failed: ~p, ~p, ~p", [C, E, S]),
+%%             ?FAIL({accept, C, E, S})
+%%     end.
+
+
+sock_close(Sock) ->
+    try socket:close(Sock) of
+        ok ->
+            ok;
+        {error, Reason} ->
+            i("sock_close -> error: ~p", [Reason]),
+            ?FAIL({close, Reason})
+    catch
+        C:E:S ->
+            i("sock_close -> failed: ~p, ~p, ~p", [C, E, S]),
+            ?FAIL({close, C, E, S})
+    end.
+
+
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+not_yet_implemented() ->
+    skip("not yet implemented").
+
+skip(Reason) ->
+    throw({skip, Reason}).
+
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+t() ->
+    os:timestamp().
+
+
+tdiff({A1, B1, C1} = _T1x, {A2, B2, C2} = _T2x) ->
+    T1 = A1*1000000000+B1*1000+(C1 div 1000), 
+    T2 = A2*1000000000+B2*1000+(C2 div 1000), 
+    T2 - T1.
+
+
+formated_timestamp() ->
+    format_timestamp(os:timestamp()).
+
+format_timestamp({_N1, _N2, _N3} = TS) ->
+    {_Date, Time}   = calendar:now_to_local_time(TS),
+    %% {YYYY,MM,DD}   = Date,
+    {Hour,Min,Sec} = Time,
+    %% FormatTS = 
+    %%     io_lib:format("~.4w-~.2.0w-~.2.0w ~.2.0w:~.2.0w:~.2.0w.~w",
+    %%                   [YYYY, MM, DD, Hour, Min, Sec, N3]),  
+    FormatTS = io_lib:format("~.2.0w:~.2.0w:~.2.0w", [Hour, Min, Sec]),  
+    lists:flatten(FormatTS).
+
+   
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+set_tc_name(N) when is_atom(N) ->
+    set_tc_name(atom_to_list(N));
+set_tc_name(N) when is_list(N) ->
+    put(tc_name, N).
+
+%% get_tc_name() ->
+%%     get(tc_name).
+
+tc_begin(TC) ->
+    set_tc_name(TC),
+    tc_print("begin ***",
+             "~n----------------------------------------------------~n", "").
+    
+tc_end(Result) when is_list(Result) ->
+    tc_print("done: ~s", [Result], 
+             "", "----------------------------------------------------~n~n"),
+    ok.
+
+
+tc_try(Case, Fun) when is_atom(Case) andalso is_function(Fun, 0) ->
+    tc_begin(Case),
+    try 
+        begin
+            Fun(),
+            tc_end("ok")
+        end
+    catch
+        throw:{skip, _} = SKIP ->
+            tc_end("skipping"),
+            SKIP;
+        Class:Error:Stack ->
+            tc_end("failed"),
+            erlang:raise(Class, Error, Stack)
+    end.
+
+
+tc_print(F, Before, After) ->
+    tc_print(F, [], Before, After).
+
+tc_print(F, A, Before, After) ->
+    Name = tc_which_name(),
+    FStr = f("*** [~s][~s][~p] " ++ F ++ "~n", 
+             [formated_timestamp(),Name,self()|A]),
+    io:format(user, Before ++ FStr ++ After, []).
+
+tc_which_name() ->
+    case get(tc_name) of
+        undefined ->
+            case get(sname) of
+                undefined ->
+                    "";
+                SName when is_list(SName) ->
+                    SName
+            end;
+        Name when is_list(Name) ->
+            Name
+    end.
+    
+    
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+f(F, A) ->
+    lists:flatten(io_lib:format(F, A)).
+
+%% p(F) ->
+%%     p(F, []).
+
+%% p(F, A) ->
+%%     p(F, A, "", "").
+
+%% p(F, A, Before, After) when is_list(Before) andalso is_list(After) ->
+%%     TcName = 
+%%         case get(tc_name) of
+%%             undefined ->
+%%                 case get(sname) of
+%%                     undefined ->
+%%                         "";
+%%                     SName when is_list(SName) ->
+%%                         SName
+%%                 end;
+%%             Name when is_list(Name) ->
+%%                 Name
+%%         end,
+%%     FStr = f("*** [~s][~s][~p] " ++ F ++ "~n", 
+%%              [formated_timestamp(),TcName,self()|A]),
+%%     i(Before ++ FStr ++ After, []).
+
+
+i(F) ->
+    i(F, []).
+
+i(F, A) ->
+    FStr = f("[~s] " ++ F, [formated_timestamp()|A]),
+    io:format(user, FStr ++ "~n", []),
+    io:format(FStr, []).
+