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-rw-r--r--lib/kernel/doc/src/gen_tcp.xml5
-rw-r--r--lib/kernel/src/gen_sctp.erl30
-rw-r--r--lib/kernel/src/gen_tcp.erl36
-rw-r--r--lib/kernel/src/gen_udp.erl34
-rw-r--r--lib/kernel/test/gen_sctp_SUITE.erl59
-rw-r--r--lib/kernel/test/gen_tcp_api_SUITE.erl57
-rw-r--r--lib/kernel/test/gen_tcp_misc_SUITE.erl17
-rw-r--r--lib/kernel/test/gen_udp_SUITE.erl60
-rw-r--r--lib/kernel/test/inet_SUITE.erl30
9 files changed, 272 insertions, 56 deletions
diff --git a/lib/kernel/doc/src/gen_tcp.xml b/lib/kernel/doc/src/gen_tcp.xml
index 032dcc5251..8e7192a496 100644
--- a/lib/kernel/doc/src/gen_tcp.xml
+++ b/lib/kernel/doc/src/gen_tcp.xml
@@ -4,7 +4,7 @@
<erlref>
<header>
<copyright>
- <year>1997</year><year>2009</year>
+ <year>1997</year><year>2010</year>
<holder>Ericsson AB. All Rights Reserved.</holder>
</copyright>
<legalnotice>
@@ -284,9 +284,10 @@ socket()
<type>
<v>Socket = socket()</v>
<v>Length = int()</v>
- <v>Packet = [char()] | binary()</v>
+ <v>Packet = [char()] | binary() | HttpPacket</v>
<v>Timeout = int() | infinity</v>
<v>Reason = closed | posix()</v>
+ <v>HttpPacket = see the description of <c>HttpPacket</c> in <seealso marker="erts:erlang#decode_packet/3">erlang:decode_packet/3</seealso></v>
</type>
<desc>
<p>This function receives a packet from a socket in passive
diff --git a/lib/kernel/src/gen_sctp.erl b/lib/kernel/src/gen_sctp.erl
index a1542ab507..cccfa75005 100644
--- a/lib/kernel/src/gen_sctp.erl
+++ b/lib/kernel/src/gen_sctp.erl
@@ -39,7 +39,7 @@ open() ->
open([]).
open(Opts) when is_list(Opts) ->
- Mod = mod(Opts),
+ Mod = mod(Opts, undefined),
case Mod:open(Opts) of
{error,badarg} ->
erlang:error(badarg, [Opts]);
@@ -234,17 +234,27 @@ controlling_process(S, Pid) ->
%% Utilites
%%
-%% Get the SCTP moudule
-mod() -> inet_db:sctp_module().
+%% Get the SCTP module, but IPv6 address overrides default IPv4
+mod(Address) ->
+ case inet_db:sctp_module() of
+ inet_sctp when tuple_size(Address) =:= 8 ->
+ inet6_sctp;
+ Mod ->
+ Mod
+ end.
%% Get the SCTP module, but option sctp_module|inet|inet6 overrides
-mod([{sctp_module,Mod}|_]) ->
+mod([{sctp_module,Mod}|_], _Address) ->
Mod;
-mod([inet|_]) ->
+mod([inet|_], _Address) ->
inet_sctp;
-mod([inet6|_]) ->
+mod([inet6|_], _Address) ->
inet6_sctp;
-mod([_|Opts]) ->
- mod(Opts);
-mod([]) ->
- mod().
+mod([{ip, Address}|Opts], _) ->
+ mod(Opts, Address);
+mod([{ifaddr, Address}|Opts], _) ->
+ mod(Opts, Address);
+mod([_|Opts], Address) ->
+ mod(Opts, Address);
+mod([], Address) ->
+ mod(Address).
diff --git a/lib/kernel/src/gen_tcp.erl b/lib/kernel/src/gen_tcp.erl
index 7401b06a64..16a87d71b6 100644
--- a/lib/kernel/src/gen_tcp.erl
+++ b/lib/kernel/src/gen_tcp.erl
@@ -1,7 +1,7 @@
%%
%% %CopyrightBegin%
%%
-%% Copyright Ericsson AB 1997-2009. All Rights Reserved.
+%% Copyright Ericsson AB 1997-2010. All Rights Reserved.
%%
%% The contents of this file are subject to the Erlang Public License,
%% Version 1.1, (the "License"); you may not use this file except in
@@ -46,7 +46,7 @@ connect(Address, Port, Opts, Time) ->
end.
connect1(Address,Port,Opts,Timer) ->
- Mod = mod(Opts),
+ Mod = mod(Opts, Address),
case Mod:getaddrs(Address,Timer) of
{ok,IPs} ->
case Mod:getserv(Port) of
@@ -73,7 +73,7 @@ try_connect([], _Port, _Opts, _Timer, _Mod, Err) ->
%% Listen on a tcp port
%%
listen(Port, Opts) ->
- Mod = mod(Opts),
+ Mod = mod(Opts, undefined),
case Mod:getserv(Port) of
{ok,TP} ->
Mod:listen(TP, Opts);
@@ -173,20 +173,30 @@ controlling_process(S, NewOwner) ->
%% Create a port/socket from a file descriptor
%%
fdopen(Fd, Opts) ->
- Mod = mod(Opts),
+ Mod = mod(Opts, undefined),
Mod:fdopen(Fd, Opts).
-%% Get the tcp_module
-mod() -> inet_db:tcp_module().
+%% Get the tcp_module, but IPv6 address overrides default IPv4
+mod(Address) ->
+ case inet_db:tcp_module() of
+ inet_tcp when tuple_size(Address) =:= 8 ->
+ inet6_tcp;
+ Mod ->
+ Mod
+ end.
%% Get the tcp_module, but option tcp_module|inet|inet6 overrides
-mod([{tcp_module,Mod}|_]) ->
+mod([{tcp_module,Mod}|_], _Address) ->
Mod;
-mod([inet|_]) ->
+mod([inet|_], _Address) ->
inet_tcp;
-mod([inet6|_]) ->
+mod([inet6|_], _Address) ->
inet6_tcp;
-mod([_|Opts]) ->
- mod(Opts);
-mod([]) ->
- mod().
+mod([{ip, Address}|Opts], _) ->
+ mod(Opts, Address);
+mod([{ifaddr, Address}|Opts], _) ->
+ mod(Opts, Address);
+mod([_|Opts], Address) ->
+ mod(Opts, Address);
+mod([], Address) ->
+ mod(Address).
diff --git a/lib/kernel/src/gen_udp.erl b/lib/kernel/src/gen_udp.erl
index 6bded4bda6..99020c7b6c 100644
--- a/lib/kernel/src/gen_udp.erl
+++ b/lib/kernel/src/gen_udp.erl
@@ -1,7 +1,7 @@
%%
%% %CopyrightBegin%
%%
-%% Copyright Ericsson AB 1997-2009. All Rights Reserved.
+%% Copyright Ericsson AB 1997-2010. All Rights Reserved.
%%
%% The contents of this file are subject to the Erlang Public License,
%% Version 1.1, (the "License"); you may not use this file except in
@@ -29,7 +29,7 @@ open(Port) ->
open(Port, []).
open(Port, Opts) ->
- Mod = mod(Opts),
+ Mod = mod(Opts, undefined),
{ok,UP} = Mod:getserv(Port),
Mod:open(UP, Opts).
@@ -97,21 +97,31 @@ controlling_process(S, NewOwner) ->
%% Create a port/socket from a file descriptor
%%
fdopen(Fd, Opts) ->
- Mod = mod(),
+ Mod = mod(Opts, undefined),
Mod:fdopen(Fd, Opts).
-%% Get the udp_module
-mod() -> inet_db:udp_module().
+%% Get the udp_module, but IPv6 address overrides default IPv4
+mod(Address) ->
+ case inet_db:udp_module() of
+ inet_udp when tuple_size(Address) =:= 8 ->
+ inet6_udp;
+ Mod ->
+ Mod
+ end.
%% Get the udp_module, but option udp_module|inet|inet6 overrides
-mod([{udp_module,Mod}|_]) ->
+mod([{udp_module,Mod}|_], _Address) ->
Mod;
-mod([inet|_]) ->
+mod([inet|_], _Address) ->
inet_udp;
-mod([inet6|_]) ->
+mod([inet6|_], _Address) ->
inet6_udp;
-mod([_|Opts]) ->
- mod(Opts);
-mod([]) ->
- mod().
+mod([{ip, Address}|Opts], _) ->
+ mod(Opts, Address);
+mod([{ifaddr, Address}|Opts], _) ->
+ mod(Opts, Address);
+mod([_|Opts], Address) ->
+ mod(Opts, Address);
+mod([], Address) ->
+ mod(Address).
diff --git a/lib/kernel/test/gen_sctp_SUITE.erl b/lib/kernel/test/gen_sctp_SUITE.erl
index eb06d4324b..9aa94a0868 100644
--- a/lib/kernel/test/gen_sctp_SUITE.erl
+++ b/lib/kernel/test/gen_sctp_SUITE.erl
@@ -27,12 +27,12 @@
-export(
[basic/1,
api_open_close/1,api_listen/1,api_connect_init/1,api_opts/1,
- xfer_min/1,xfer_active/1,def_sndrcvinfo/1]).
+ xfer_min/1,xfer_active/1,def_sndrcvinfo/1,implicit_inet6/1]).
all(suite) ->
[basic,
api_open_close,api_listen,api_connect_init,api_opts,
- xfer_min,xfer_active,def_sndrcvinfo].
+ xfer_min,xfer_active,def_sndrcvinfo,implicit_inet6].
init_per_testcase(_Func, Config) ->
Dog = test_server:timetrap(test_server:seconds(15)),
@@ -551,3 +551,58 @@ api_opts(Config) when is_list(Config) ->
{{error,einval},{unix,sunos}} ->
ok
end.
+
+implicit_inet6(Config) when is_list(Config) ->
+ ?line Hostname = ok(inet:gethostname()),
+ ?line
+ case gen_sctp:open(0, [inet6]) of
+ {ok,S1} ->
+ ?line
+ case inet:getaddr(Hostname, inet6) of
+ {ok,Host} ->
+ ?line Loopback = {0,0,0,0,0,0,0,1},
+ ?line io:format("~s ~p~n", ["Loopback",Loopback]),
+ ?line implicit_inet6(S1, Loopback),
+ ?line ok = gen_sctp:close(S1),
+ %%
+ ?line Localhost =
+ ok(inet:getaddr("localhost", inet6)),
+ ?line io:format("~s ~p~n", ["localhost",Localhost]),
+ ?line S2 =
+ ok(gen_sctp:open(0, [{ip,Localhost}])),
+ ?line implicit_inet6(S2, Localhost),
+ ?line ok = gen_sctp:close(S2),
+ %%
+ ?line io:format("~s ~p~n", [Hostname,Host]),
+ ?line S3 =
+ ok(gen_sctp:open(0, [{ifaddr,Host}])),
+ ?line implicit_inet6(S3, Host),
+ ?line ok = gen_sctp:close(S1);
+ {error,eafnosupport} ->
+ ?line ok = gen_sctp:close(S1),
+ {skip,"Can not look up IPv6 address"}
+ end;
+ _ ->
+ {skip,"IPv6 not supported"}
+ end.
+
+implicit_inet6(S1, Addr) ->
+ ?line ok = gen_sctp:listen(S1, true),
+ ?line P1 = ok(inet:port(S1)),
+ ?line S2 = ok(gen_sctp:open(0, [inet6])),
+ ?line P2 = ok(inet:port(S2)),
+ ?line #sctp_assoc_change{state=comm_up} =
+ ok(gen_sctp:connect(S2, Addr, P1, [])),
+ ?line case ok(gen_sctp:recv(S1)) of
+ {Addr,P2,[],#sctp_assoc_change{state=comm_up}} ->
+ ok
+ end,
+ ?line case ok(inet:sockname(S1)) of
+ {Addr,P1} -> ok;
+ {{0,0,0,0,0,0,0,0},P1} -> ok
+ end,
+ ?line case ok(inet:sockname(S2)) of
+ {Addr,P2} -> ok;
+ {{0,0,0,0,0,0,0,0},P2} -> ok
+ end,
+ ?line ok = gen_sctp:close(S2).
diff --git a/lib/kernel/test/gen_tcp_api_SUITE.erl b/lib/kernel/test/gen_tcp_api_SUITE.erl
index 11d19aaa82..94637290a1 100644
--- a/lib/kernel/test/gen_tcp_api_SUITE.erl
+++ b/lib/kernel/test/gen_tcp_api_SUITE.erl
@@ -1,7 +1,7 @@
%%
%% %CopyrightBegin%
%%
-%% Copyright Ericsson AB 1998-2009. All Rights Reserved.
+%% Copyright Ericsson AB 1998-2010. All Rights Reserved.
%%
%% The contents of this file are subject to the Erlang Public License,
%% Version 1.1, (the "License"); you may not use this file except in
@@ -30,10 +30,11 @@
t_connect/1, t_connect_bad/1,
t_recv/1, t_recv_timeout/1, t_recv_eof/1,
t_shutdown_write/1, t_shutdown_both/1, t_shutdown_error/1,
- t_fdopen/1]).
+ t_fdopen/1, t_implicit_inet6/1]).
all(suite) -> [t_accept, t_connect, t_recv, t_shutdown_write,
- t_shutdown_both, t_shutdown_error, t_fdopen].
+ t_shutdown_both, t_shutdown_error, t_fdopen,
+ t_implicit_inet6].
init_per_testcase(_Func, Config) ->
Dog = test_server:timetrap(test_server:seconds(60)),
@@ -156,6 +157,54 @@ t_fdopen(Config) when is_list(Config) ->
ok.
+%%% implicit inet6 option to api functions
+
+t_implicit_inet6(Config) when is_list(Config) ->
+ ?line Hostname = ok(inet:gethostname()),
+ ?line
+ case gen_tcp:listen(0, [inet6]) of
+ {ok,S1} ->
+ ?line
+ case inet:getaddr(Hostname, inet6) of
+ {ok,Host} ->
+ ?line Loopback = {0,0,0,0,0,0,0,1},
+ ?line io:format("~s ~p~n", ["Loopback",Loopback]),
+ ?line implicit_inet6(S1, Loopback),
+ ?line ok = gen_tcp:close(S1),
+ %%
+ ?line Localhost =
+ ok(inet:getaddr("localhost", inet6)),
+ ?line io:format("~s ~p~n", ["localhost",Localhost]),
+ ?line S2 = ok(gen_tcp:listen(0, [{ip,Localhost}])),
+ ?line implicit_inet6(S2, Localhost),
+ ?line ok = gen_tcp:close(S2),
+ %%
+ ?line io:format("~s ~p~n", [Hostname,Host]),
+ ?line S3 = ok(gen_tcp:listen(0, [{ifaddr,Host}])),
+ ?line implicit_inet6(S3, Host),
+ ?line ok = gen_tcp:close(S1);
+ {error,eafnosupport} ->
+ ?line ok = gen_tcp:close(S1),
+ {skip,"Can not look up IPv6 address"}
+ end;
+ _ ->
+ {skip,"IPv6 not supported"}
+ end.
+
+implicit_inet6(S, Addr) ->
+ ?line P = ok(inet:port(S)),
+ ?line S2 = ok(gen_tcp:connect(Addr, P, [])),
+ ?line P2 = ok(inet:port(S2)),
+ ?line S1 = ok(gen_tcp:accept(S)),
+ ?line P1 = P = ok(inet:port(S1)),
+ ?line {Addr,P2} = ok(inet:peername(S1)),
+ ?line {Addr,P1} = ok(inet:peername(S2)),
+ ?line {Addr,P1} = ok(inet:sockname(S1)),
+ ?line {Addr,P2} = ok(inet:sockname(S2)),
+ ?line ok = gen_tcp:close(S2),
+ ?line ok = gen_tcp:close(S1).
+
+
%%% Utilities
@@ -217,3 +266,5 @@ unused_ip(A, B, C, D) ->
{ok, _} -> unused_ip(A, B, C, D+1);
{error, _} -> {ok, {A, B, C, D}}
end.
+
+ok({ok,V}) -> V.
diff --git a/lib/kernel/test/gen_tcp_misc_SUITE.erl b/lib/kernel/test/gen_tcp_misc_SUITE.erl
index 5d726a3b1b..d73c5fab56 100644
--- a/lib/kernel/test/gen_tcp_misc_SUITE.erl
+++ b/lib/kernel/test/gen_tcp_misc_SUITE.erl
@@ -1,19 +1,19 @@
%%
%% %CopyrightBegin%
-%%
-%% Copyright Ericsson AB 1998-2009. All Rights Reserved.
-%%
+%%
+%% Copyright Ericsson AB 1998-2010. All Rights Reserved.
+%%
%% The contents of this file are subject to the Erlang Public License,
%% Version 1.1, (the "License"); you may not use this file except in
%% compliance with the License. You should have received a copy of the
%% Erlang Public License along with this software. If not, it can be
%% retrieved online at http://www.erlang.org/.
-%%
+%%
%% Software distributed under the License is distributed on an "AS IS"
%% basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
%% the License for the specific language governing rights and limitations
%% under the License.
-%%
+%%
%% %CopyrightEnd%
%%
-module(gen_tcp_misc_SUITE).
@@ -957,12 +957,11 @@ http_bad_packet(Config) when is_list(Config) ->
http_worker(S) ->
case gen_tcp:recv(S, 0, 30000) of
+ {ok,{http_error,Error}} ->
+ io:format("Http error: ~s\n", [Error]);
{ok,Data} ->
io:format("Data: ~p\n", [Data]),
- http_worker(S);
- {error,Rsn} ->
- io:format("Error: ~p\n", [Rsn]),
- ok
+ http_worker(S)
end.
http_bad_client(Port) ->
diff --git a/lib/kernel/test/gen_udp_SUITE.erl b/lib/kernel/test/gen_udp_SUITE.erl
index fa1991872b..44dd8607b9 100644
--- a/lib/kernel/test/gen_udp_SUITE.erl
+++ b/lib/kernel/test/gen_udp_SUITE.erl
@@ -1,7 +1,7 @@
%%
%% %CopyrightBegin%
%%
-%% Copyright Ericsson AB 1998-2009. All Rights Reserved.
+%% Copyright Ericsson AB 1998-2010. All Rights Reserved.
%%
%% The contents of this file are subject to the Erlang Public License,
%% Version 1.1, (the "License"); you may not use this file except in
@@ -34,12 +34,12 @@
-export([send_to_closed/1,
buffer_size/1, binary_passive_recv/1, bad_address/1,
- read_packets/1, open_fd/1, connect/1]).
+ read_packets/1, open_fd/1, connect/1, implicit_inet6/1]).
all(suite) ->
[send_to_closed,
buffer_size, binary_passive_recv, bad_address, read_packets,
- open_fd, connect].
+ open_fd, connect, implicit_inet6].
init_per_testcase(_Case, Config) ->
?line Dog=test_server:timetrap(?default_timeout),
@@ -425,3 +425,57 @@ connect(Config) when is_list(Config) ->
ok = gen_udp:send(S2, <<16#deadbeef:32>>),
{error,econnrefused} = gen_udp:recv(S2, 0, 5),
ok.
+
+implicit_inet6(Config) when is_list(Config) ->
+ ?line Hostname = ok(inet:gethostname()),
+ ?line Active = {active,false},
+ ?line
+ case gen_udp:open(0, [inet6,Active]) of
+ {ok,S1} ->
+ ?line
+ case inet:getaddr(Hostname, inet6) of
+ {ok,Host} ->
+ ?line Loopback = {0,0,0,0,0,0,0,1},
+ ?line io:format("~s ~p~n", ["Loopback",Loopback]),
+ ?line implicit_inet6(S1, Active, Loopback),
+ ?line ok = gen_udp:close(S1),
+ %%
+ ?line Localhost =
+ ok(inet:getaddr("localhost", inet6)),
+ ?line io:format("~s ~p~n", ["localhost",Localhost]),
+ ?line S2 =
+ ok(gen_udp:open(0, [{ip,Localhost},Active])),
+ ?line implicit_inet6(S2, Active, Localhost),
+ ?line ok = gen_udp:close(S2),
+ %%
+ ?line io:format("~s ~p~n", [Hostname,Host]),
+ ?line S3 =
+ ok(gen_udp:open(0, [{ifaddr,Host},Active])),
+ ?line implicit_inet6(S3, Active, Host),
+ ?line ok = gen_udp:close(S1);
+ {error,eafnosupport} ->
+ ?line ok = gen_udp:close(S1),
+ {skip,"Can not look up IPv6 address"}
+ end;
+ _ ->
+ {skip,"IPv6 not supported"}
+ end.
+
+implicit_inet6(S1, Active, Addr) ->
+ ?line P1 = ok(inet:port(S1)),
+ ?line S2 = ok(gen_udp:open(0, [inet6,Active])),
+ ?line P2 = ok(inet:port(S2)),
+ ?line ok = gen_udp:connect(S2, Addr, P1),
+ ?line ok = gen_udp:connect(S1, Addr, P2),
+ ?line {Addr,P2} = ok(inet:peername(S1)),
+ ?line {Addr,P1} = ok(inet:peername(S2)),
+ ?line {Addr,P1} = ok(inet:sockname(S1)),
+ ?line {Addr,P2} = ok(inet:sockname(S2)),
+ ?line ok = gen_udp:send(S1, Addr, P2, "ping"),
+ ?line {Addr,P1,"ping"} = ok(gen_udp:recv(S2, 1024, 1000)),
+ ?line ok = gen_udp:send(S2, Addr, P1, "pong"),
+ ?line {Addr,P2,"pong"} = ok(gen_udp:recv(S1, 1024)),
+ ?line ok = gen_udp:close(S2).
+
+
+ok({ok,V}) -> V.
diff --git a/lib/kernel/test/inet_SUITE.erl b/lib/kernel/test/inet_SUITE.erl
index eb8f918491..f4f27933a5 100644
--- a/lib/kernel/test/inet_SUITE.erl
+++ b/lib/kernel/test/inet_SUITE.erl
@@ -26,7 +26,8 @@
t_gethostbyaddr_v6/1, t_getaddr_v6/1, t_gethostbyname_v6/1,
ipv4_to_ipv6/1, host_and_addr/1, parse/1, t_gethostnative/1,
gethostnative_parallell/1, cname_loop/1,
- gethostnative_soft_restart/1,gethostnative_debug_level/1,getif/1]).
+ gethostnative_soft_restart/1,gethostnative_debug_level/1,getif/1,
+ getif_ifr_name_overflow/1,getservbyname_overflow/1]).
-export([get_hosts/1, get_ipv6_hosts/1, parse_hosts/1, parse_address/1,
kill_gethost/0, parallell_gethost/0]).
@@ -39,7 +40,7 @@ all(suite) ->
ipv4_to_ipv6, host_and_addr, parse,t_gethostnative,
gethostnative_parallell, cname_loop,
gethostnative_debug_level,gethostnative_soft_restart,
- getif].
+ getif,getif_ifr_name_overflow,getservbyname_overflow].
init_per_testcase(_Func, Config) ->
Dog = test_server:timetrap(test_server:seconds(60)),
@@ -876,6 +877,17 @@ getif(Config) when is_list(Config) ->
?line {ok,Address} = inet:getaddr(Hostname, inet),
?line {ok,Loopback} = inet:getaddr("localhost", inet),
?line {ok,Interfaces} = inet:getiflist(),
+ ?line HWAs =
+ lists:sort(
+ lists:foldl(
+ fun (I, Acc) ->
+ case inet:ifget(I, [hwaddr]) of
+ {ok,[{hwaddr,A}]} -> [A|Acc];
+ {ok,[]} -> Acc
+ end
+ end, [], Interfaces)),
+ ?line io:format("HWAs = ~p~n", [HWAs]),
+ ?line length(HWAs) > 0 orelse ?t:fail(no_HWAs),
?line Addresses =
lists:sort(
lists:foldl(
@@ -891,6 +903,20 @@ getif(Config) when is_list(Config) ->
?line true = ip_member(Loopback, Addresses),
?line ok.
+getif_ifr_name_overflow(doc) ->
+ "Test long interface names do not overrun buffer";
+getif_ifr_name_overflow(Config) when is_list(Config) ->
+ %% emulator should not crash
+ ?line {ok,[]} = inet:ifget(lists:duplicate(128, "x"), [addr]),
+ ok.
+
+getservbyname_overflow(doc) ->
+ "Test long service names do not overrun buffer";
+getservbyname_overflow(Config) when is_list(Config) ->
+ %% emulator should not crash
+ ?line {error,einval} = inet:getservbyname(list_to_atom(lists:flatten(lists:duplicate(128, "x"))), tcp),
+ ok.
+
%% Works just like lists:member/2, except that any {127,_,_,_} tuple
%% matches any other {127,_,_,_}. We do this to handle Linux systems
%% that use (for instance) 127.0.1.1 as the IP address for the hostname.