%%
%% %CopyrightBegin%
%%
%% Copyright Ericsson AB 1998-2018. 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(gen_tcp_api_SUITE).
%% Tests the documented API for the gen_tcp functions. The "normal" cases
%% are not tested here, because they are tested indirectly in this and
%% and other test suites.
-include_lib("common_test/include/ct.hrl").
-include_lib("kernel/include/inet.hrl").
-export([all/0, suite/0,groups/0,init_per_suite/1, end_per_suite/1,
init_per_group/2,end_per_group/2,
init_per_testcase/2, end_per_testcase/2,
t_connect_timeout/1, t_accept_timeout/1,
t_connect_bad/1,
t_recv_timeout/1, t_recv_eof/1, t_recv_delim/1,
t_shutdown_write/1, t_shutdown_both/1, t_shutdown_error/1,
t_shutdown_async/1,
t_fdopen/1, t_fdconnect/1, t_implicit_inet6/1,
t_local_basic/1, t_local_unbound/1, t_local_fdopen/1,
t_local_fdopen_listen/1, t_local_fdopen_listen_unbound/1,
t_local_fdopen_connect/1, t_local_fdopen_connect_unbound/1,
t_local_abstract/1, t_accept_inet6_tclass/1]).
-export([getsockfd/0,closesockfd/1]).
suite() ->
[{ct_hooks,[ts_install_cth]},
{timetrap,{minutes,1}}].
all() ->
[{group, t_accept}, {group, t_connect}, {group, t_recv},
t_shutdown_write, t_shutdown_both, t_shutdown_error,
t_shutdown_async, t_fdopen, t_fdconnect, t_implicit_inet6,
t_accept_inet6_tclass,
{group, t_local}].
groups() ->
[{t_accept, [], [t_accept_timeout]},
{t_connect, [], [t_connect_timeout, t_connect_bad]},
{t_recv, [], [t_recv_timeout, t_recv_eof, t_recv_delim]},
{t_local, [],
[t_local_basic, t_local_unbound, t_local_fdopen,
t_local_fdopen_listen, t_local_fdopen_listen_unbound,
t_local_fdopen_connect, t_local_fdopen_connect_unbound,
t_local_abstract]}].
init_per_suite(Config) ->
Config.
end_per_suite(_Config) ->
ok.
init_per_group(t_local, Config) ->
case gen_tcp:connect({local,<<"/">>}, 0, []) of
{error,eafnosupport} ->
{skip, "AF_LOCAL not supported"};
{error,_} ->
Config
end;
init_per_group(_GroupName, Config) ->
Config.
end_per_group(t_local, _Config) ->
delete_local_filenames();
end_per_group(_, _Config) ->
ok.
init_per_testcase(Func, Config)
when Func =:= undefined -> % Insert your testcase name here
dbg:tracer(),
dbg:p(self(), c),
dbg:tpl(prim_inet, cx),
dbg:tpl(local_tcp, cx),
dbg:tpl(inet, cx),
dbg:tpl(gen_tcp, cx),
Config;
init_per_testcase(_Func, Config) ->
Config.
end_per_testcase(_Func, _Config) ->
dbg:stop().
%%% gen_tcp:accept/1,2
%% Test that gen_tcp:accept/2 (with timeout) works.
t_accept_timeout(Config) when is_list(Config) ->
{ok, L} = gen_tcp:listen(0, []),
timeout({gen_tcp, accept, [L, 200]}, 0.2, 1.0).
%%% gen_tcp:connect/X
%% Test that gen_tcp:connect/4 (with timeout) works.
t_connect_timeout(Config) when is_list(Config) ->
%%BadAddr = {134,138,177,16},
%%TcpPort = 80,
{ok, BadAddr} = unused_ip(),
TcpPort = 45638,
ok = io:format("Connecting to ~p, port ~p", [BadAddr, TcpPort]),
connect_timeout({gen_tcp,connect,[BadAddr,TcpPort,[],200]}, 0.2, 5.0).
%% Test that gen_tcp:connect/3 handles non-existings hosts, and other
%% invalid things.
t_connect_bad(Config) when is_list(Config) ->
NonExistingPort = 45638, % Not in use, I hope.
{error, Reason1} = gen_tcp:connect(localhost, NonExistingPort, []),
io:format("Error for connection attempt to port not in use: ~p",
[Reason1]),
{error, Reason2} = gen_tcp:connect("non-existing-host-xxx", 7, []),
io:format("Error for connection attempt to non-existing host: ~p",
[Reason2]),
ok.
%%% gen_tcp:recv/X
%% Test that gen_tcp:recv/3 (with timeout works).
t_recv_timeout(Config) when is_list(Config) ->
{ok, L} = gen_tcp:listen(0, []),
{ok, Port} = inet:port(L),
{ok, Client} = gen_tcp:connect(localhost, Port, [{active, false}]),
{ok, _A} = gen_tcp:accept(L),
timeout({gen_tcp, recv, [Client, 0, 200]}, 0.2, 5.0).
%% Test that end of file on a socket is reported correctly.
t_recv_eof(Config) when is_list(Config) ->
{ok, L} = gen_tcp:listen(0, []),
{ok, Port} = inet:port(L),
{ok, Client} = gen_tcp:connect(localhost, Port, [{active, false}]),
{ok, A} = gen_tcp:accept(L),
ok = gen_tcp:close(A),
{error, closed} = gen_tcp:recv(Client, 0),
ok.
%% Test using message delimiter $X.
t_recv_delim(Config) when is_list(Config) ->
{ok, L} = gen_tcp:listen(0, []),
{ok, Port} = inet:port(L),
Opts = [{active,false},{packet,line},{line_delimiter,$X}],
{ok, Client} = gen_tcp:connect(localhost, Port, Opts),
{ok, A} = gen_tcp:accept(L),
ok = gen_tcp:send(A, "abcXefgX"),
{ok, "abcX"} = gen_tcp:recv(Client, 0, 200),
{ok, "efgX"} = gen_tcp:recv(Client, 0, 200),
ok = gen_tcp:close(Client),
ok = gen_tcp:close(A),
ok.
%%% gen_tcp:shutdown/2
t_shutdown_write(Config) when is_list(Config) ->
{ok, L} = gen_tcp:listen(0, []),
{ok, Port} = inet:port(L),
{ok, Client} = gen_tcp:connect(localhost, Port, [{active, false}]),
{ok, A} = gen_tcp:accept(L),
ok = gen_tcp:shutdown(A, write),
{error, closed} = gen_tcp:recv(Client, 0),
ok.
t_shutdown_both(Config) when is_list(Config) ->
{ok, L} = gen_tcp:listen(0, []),
{ok, Port} = inet:port(L),
{ok, Client} = gen_tcp:connect(localhost, Port, [{active, false}]),
{ok, A} = gen_tcp:accept(L),
ok = gen_tcp:shutdown(A, read_write),
{error, closed} = gen_tcp:recv(Client, 0),
ok.
t_shutdown_error(Config) when is_list(Config) ->
{ok, L} = gen_tcp:listen(0, []),
{error, enotconn} = gen_tcp:shutdown(L, read_write),
ok = gen_tcp:close(L),
{error, closed} = gen_tcp:shutdown(L, read_write),
ok.
t_shutdown_async(Config) when is_list(Config) ->
{OS, _} = os:type(),
{ok, L} = gen_tcp:listen(0, [{sndbuf, 4096}]),
{ok, Port} = inet:port(L),
{ok, Client} = gen_tcp:connect(localhost, Port,
[{recbuf, 4096},
{active, false}]),
{ok, S} = gen_tcp:accept(L),
PayloadSize = 1024 * 1024,
Payload = lists:duplicate(PayloadSize, $.),
ok = gen_tcp:send(S, Payload),
case erlang:port_info(S, queue_size) of
{queue_size, N} when N > 0 -> ok;
{queue_size, 0} when OS =:= win32 -> ok;
{queue_size, 0} = T -> ct:fail({unexpected, T})
end,
ok = gen_tcp:shutdown(S, write),
{ok, Buf} = gen_tcp:recv(Client, PayloadSize),
{error, closed} = gen_tcp:recv(Client, 0),
case length(Buf) of
PayloadSize -> ok;
Sz -> ct:fail({payload_size,
{expected, PayloadSize},
{received, Sz}})
end.
%%% gen_tcp:fdopen/2
t_fdopen(Config) when is_list(Config) ->
Question = "Aaaa... Long time ago in a small town in Germany,",
Question1 = list_to_binary(Question),
Question2 = [<<"Aaaa">>, "... ", $L, <<>>, $o, "ng time ago ",
["in ", [], <<"a small town">>, [" in Germany,", <<>>]]],
Question1 = iolist_to_binary(Question2),
Answer = "there was a shoemaker, Schumacher was his name.",
{ok, L} = gen_tcp:listen(0, [{active, false}]),
{ok, Port} = inet:port(L),
{ok, Client} = gen_tcp:connect(localhost, Port, [{active, false}]),
{ok, A} = gen_tcp:accept(L),
{ok, FD} = prim_inet:getfd(A),
{ok, Server} = gen_tcp:fdopen(FD, []),
ok = gen_tcp:send(Client, Question),
{ok, Question} = gen_tcp:recv(Server, length(Question), 2000),
ok = gen_tcp:send(Client, Question1),
{ok, Question} = gen_tcp:recv(Server, length(Question), 2000),
ok = gen_tcp:send(Client, Question2),
{ok, Question} = gen_tcp:recv(Server, length(Question), 2000),
ok = gen_tcp:send(Server, Answer),
{ok, Answer} = gen_tcp:recv(Client, length(Answer), 2000),
ok = gen_tcp:close(Client),
{error,closed} = gen_tcp:recv(A, 1, 2000),
ok = gen_tcp:close(Server),
ok = gen_tcp:close(A),
ok = gen_tcp:close(L),
ok.
t_fdconnect(Config) when is_list(Config) ->
Question = "Aaaa... Long time ago in a small town in Germany,",
Question1 = list_to_binary(Question),
Question2 = [<<"Aaaa">>, "... ", $L, <<>>, $o, "ng time ago ",
["in ", [], <<"a small town">>, [" in Germany,", <<>>]]],
Question1 = iolist_to_binary(Question2),
Answer = "there was a shoemaker, Schumacher was his name.",
Path = proplists:get_value(data_dir, Config),
Lib = "gen_tcp_api_SUITE",
ok = erlang:load_nif(filename:join(Path,Lib), []),
{ok, L} = gen_tcp:listen(0, [{active, false}]),
{ok, Port} = inet:port(L),
FD = gen_tcp_api_SUITE:getsockfd(),
{ok, Client} = gen_tcp:connect(localhost, Port, [{fd,FD},{port,20002},
{active,false}]),
{ok, Server} = gen_tcp:accept(L),
ok = gen_tcp:send(Client, Question),
{ok, Question} = gen_tcp:recv(Server, length(Question), 2000),
ok = gen_tcp:send(Client, Question1),
{ok, Question} = gen_tcp:recv(Server, length(Question), 2000),
ok = gen_tcp:send(Client, Question2),
{ok, Question} = gen_tcp:recv(Server, length(Question), 2000),
ok = gen_tcp:send(Server, Answer),
{ok, Answer} = gen_tcp:recv(Client, length(Answer), 2000),
ok = gen_tcp:close(Client),
FD = gen_tcp_api_SUITE:closesockfd(FD),
{error,closed} = gen_tcp:recv(Server, 1, 2000),
ok = gen_tcp:close(Server),
ok = gen_tcp:close(L),
ok.
%%% implicit inet6 option to api functions
t_implicit_inet6(Config) when is_list(Config) ->
Host = ok(inet:gethostname()),
case inet:getaddr(Host, inet6) of
{ok,Addr} ->
t_implicit_inet6(Host, Addr);
{error,Reason} ->
{skip,
"Can not look up IPv6 address: "
++atom_to_list(Reason)}
end.
t_implicit_inet6(Host, Addr) ->
Loopback = {0,0,0,0,0,0,0,1},
case gen_tcp:listen(0, [inet6, {ip,Loopback}]) of
{ok,S1} ->
io:format("~s ~p~n", ["::1",Loopback]),
implicit_inet6(S1, Loopback),
ok = gen_tcp:close(S1),
%%
Localaddr = ok(get_localaddr()),
S2 = ok(gen_tcp:listen(0, [{ip,Localaddr}])),
implicit_inet6(S2, Localaddr),
ok = gen_tcp:close(S2),
%%
io:format("~s ~p~n", [Host,Addr]),
S3 = ok(gen_tcp:listen(0, [{ifaddr,Addr}])),
implicit_inet6(S3, Addr),
ok = gen_tcp:close(S3);
{error,_} ->
{skip,"IPv6 not supported"}
end.
implicit_inet6(S, Addr) ->
P = ok(inet:port(S)),
S2 = ok(gen_tcp:connect(Addr, P, [])),
P2 = ok(inet:port(S2)),
S1 = ok(gen_tcp:accept(S)),
P1 = P = ok(inet:port(S1)),
{Addr,P2} = ok(inet:peername(S1)),
{Addr,P1} = ok(inet:peername(S2)),
{Addr,P1} = ok(inet:sockname(S1)),
{Addr,P2} = ok(inet:sockname(S2)),
ok = gen_tcp:close(S2),
ok = gen_tcp:close(S1).
t_local_basic(_Config) ->
SFile = local_filename(server),
SAddr = {local,bin_filename(SFile)},
CFile = local_filename(client),
CAddr = {local,bin_filename(CFile)},
_ = file:delete(SFile),
_ = file:delete(CFile),
%%
L =
ok(
gen_tcp:listen(0, [{ifaddr,{local,SFile}},{active,false}])),
C =
ok(
gen_tcp:connect(
{local,SFile}, 0, [{ifaddr,{local,CFile}},{active,false}])),
S = ok(gen_tcp:accept(L)),
SAddr = ok(inet:sockname(L)),
{error,enotconn} = inet:peername(L),
local_handshake(S, SAddr, C, CAddr),
ok = gen_tcp:close(L),
ok = gen_tcp:close(S),
ok = gen_tcp:close(C),
%%
ok = file:delete(SFile),
ok = file:delete(CFile),
ok.
t_local_unbound(_Config) ->
SFile = local_filename(server),
SAddr = {local,bin_filename(SFile)},
_ = file:delete(SFile),
%%
L = ok(gen_tcp:listen(0, [{ifaddr,SAddr},{active,false}])),
C = ok(gen_tcp:connect(SAddr, 0, [{active,false}])),
S = ok(gen_tcp:accept(L)),
SAddr = ok(inet:sockname(L)),
{error,enotconn} = inet:peername(L),
local_handshake(S, SAddr, C, {local,<<>>}),
ok = gen_tcp:close(L),
ok = gen_tcp:close(S),
ok = gen_tcp:close(C),
ok = file:delete(SFile),
ok.
t_local_fdopen(_Config) ->
SFile = local_filename(server),
SAddr = {local,bin_filename(SFile)},
_ = file:delete(SFile),
%%
L = ok(gen_tcp:listen(0, [{ifaddr,SAddr},{active,false}])),
C0 = ok(gen_tcp:connect(SAddr, 0, [{active,false}])),
Fd = ok(prim_inet:getfd(C0)),
ok = prim_inet:ignorefd(C0, true),
C = ok(gen_tcp:fdopen(Fd, [local])),
S = ok(gen_tcp:accept(L)),
SAddr = ok(inet:sockname(L)),
{error,enotconn} = inet:peername(L),
local_handshake(S, SAddr, C, {local,<<>>}),
ok = gen_tcp:close(L),
ok = gen_tcp:close(S),
ok = gen_tcp:close(C),
ok = gen_tcp:close(C0),
ok = file:delete(SFile),
ok.
t_local_fdopen_listen(_Config) ->
SFile = local_filename(server),
SAddr = {local,bin_filename(SFile)},
_ = file:delete(SFile),
L0 = ok(gen_tcp:listen(0, [{ifaddr,SAddr},{active,false}])),
Fd = ok(prim_inet:getfd(L0)),
L = ok(gen_tcp:listen(0, [{fd,Fd},local,{active,false}])),
C = ok(gen_tcp:connect(SAddr, 0, [{active,false}])),
S = ok(gen_tcp:accept(L)),
SAddr = ok(inet:sockname(L)),
{error,enotconn} = inet:peername(L),
local_handshake(S, SAddr, C, {local,<<>>}),
ok = gen_tcp:close(L),
ok = gen_tcp:close(L0),
ok = gen_tcp:close(S),
ok = gen_tcp:close(C),
ok = file:delete(SFile),
ok.
t_local_fdopen_listen_unbound(_Config) ->
SFile = local_filename(server),
SAddr = {local,bin_filename(SFile)},
_ = file:delete(SFile),
P = ok(prim_inet:open(tcp, local, stream)),
Fd = ok(prim_inet:getfd(P)),
L =
ok(gen_tcp:listen(
0, [{fd,Fd},{ifaddr,SAddr},{active,false}])),
C = ok(gen_tcp:connect(SAddr, 0, [{active,false}])),
S = ok(gen_tcp:accept(L)),
SAddr = ok(inet:sockname(L)),
{error,enotconn} = inet:peername(L),
local_handshake(S, SAddr, C, {local,<<>>}),
ok = gen_tcp:close(L),
ok = gen_tcp:close(P),
ok = gen_tcp:close(S),
ok = gen_tcp:close(C),
ok = file:delete(SFile),
ok.
t_local_fdopen_connect(_Config) ->
SFile = local_filename(server),
SAddr = {local,bin_filename(SFile)},
CFile = local_filename(client),
CAddr = {local,bin_filename(CFile)},
_ = file:delete(SFile),
_ = file:delete(CFile),
L = ok(gen_tcp:listen(0, [{ifaddr,SAddr},{active,false}])),
P = ok(prim_inet:open(tcp, local, stream)),
Fd = ok(prim_inet:getfd(P)),
C =
ok(gen_tcp:connect(
SAddr, 0, [{fd,Fd},{ifaddr,CAddr},{active,false}])),
S = ok(gen_tcp:accept(L)),
SAddr = ok(inet:sockname(L)),
{error,enotconn} = inet:peername(L),
local_handshake(S, SAddr, C, CAddr),
ok = gen_tcp:close(L),
ok = gen_tcp:close(S),
ok = gen_tcp:close(C),
ok = gen_tcp:close(P),
ok = file:delete(SFile),
ok.
t_local_fdopen_connect_unbound(_Config) ->
SFile = local_filename(server),
SAddr = {local,bin_filename(SFile)},
_ = file:delete(SFile),
L = ok(gen_tcp:listen(0, [{ifaddr,SAddr},{active,false}])),
P = ok(prim_inet:open(tcp, local, stream)),
Fd = ok(prim_inet:getfd(P)),
C = ok(gen_tcp:connect(SAddr, 0, [{fd,Fd},{active,false}])),
S = ok(gen_tcp:accept(L)),
SAddr = ok(inet:sockname(L)),
{error,enotconn} = inet:peername(L),
local_handshake(S, SAddr, C, {local,<<>>}),
ok = gen_tcp:close(L),
ok = gen_tcp:close(S),
ok = gen_tcp:close(C),
ok = gen_tcp:close(P),
ok = file:delete(SFile),
ok.
t_local_abstract(_Config) ->
case os:type() of
{unix,linux} ->
AbstAddr = {local,<<>>},
L =
ok(gen_tcp:listen(
0, [{ifaddr,AbstAddr},{active,false}])),
{local,_} = SAddr = ok(inet:sockname(L)),
C =
ok(gen_tcp:connect(
SAddr, 0, [{ifaddr,AbstAddr},{active,false}])),
{local,_} = CAddr = ok(inet:sockname(C)),
S = ok(gen_tcp:accept(L)),
{error,enotconn} = inet:peername(L),
local_handshake(S, SAddr, C, CAddr),
ok = gen_tcp:close(L),
ok = gen_tcp:close(S),
ok = gen_tcp:close(C),
ok;
_ ->
{skip,"AF_LOCAL Abstract Addresses only supported on Linux"}
end.
local_handshake(S, SAddr, C, CAddr) ->
SData = "9876543210",
CData = "0123456789",
SAddr = ok(inet:sockname(S)),
CAddr = ok(inet:sockname(C)),
CAddr = ok(inet:peername(S)),
SAddr = ok(inet:peername(C)),
ok = gen_tcp:send(C, CData),
ok = gen_tcp:send(S, SData),
CData = ok(gen_tcp:recv(S, length(CData))),
SData = ok(gen_tcp:recv(C, length(SData))),
ok.
t_accept_inet6_tclass(Config) when is_list(Config) ->
TClassOpt = {tclass,8#56 bsl 2}, % Expedited forwarding
Loopback = {0,0,0,0,0,0,0,1},
case gen_tcp:listen(0, [inet6, {ip, Loopback}, TClassOpt]) of
{ok,L} ->
LPort = ok(inet:port(L)),
Sa = ok(gen_tcp:connect(Loopback, LPort, [])),
Sb = ok(gen_tcp:accept(L)),
[TClassOpt] = ok(inet:getopts(Sb, [tclass])),
ok = gen_tcp:close(Sb),
ok = gen_tcp:close(Sa),
ok = gen_tcp:close(L),
ok;
{error,_} ->
{skip,"IPv6 TCLASS not supported"}
end.
%%% Utilities
%% Calls M:F/length(A), which should return a timeout error, and complete
%% within the given time.
timeout({M,F,A}, Lower, Upper) ->
case test_server:timecall(M, F, A) of
{Time, Result} when Time < Lower ->
ct:fail({too_short_time, Time, Result});
{Time, Result} when Time > Upper ->
ct:fail({too_long_time, Time, Result});
{_, {error, timeout}} ->
ok;
{_, Result} ->
ct:fail({unexpected_result, Result})
end.
connect_timeout({M,F,A}, Lower, Upper) ->
case test_server:timecall(M, F, A) of
{Time, Result} when Time < Lower ->
case Result of
{error,econnrefused=E} ->
{comment,"Not tested -- got error "++atom_to_list(E)};
{error,enetunreach=E} ->
{comment,"Not tested -- got error "++atom_to_list(E)};
{ok,Socket} -> % What the...
Pinfo = erlang:port_info(Socket),
Db = inet_db:lookup_socket(Socket),
Peer = inet:peername(Socket),
ct:fail({too_short_time, Time,
[Result,Pinfo,Db,Peer]});
_ ->
ct:fail({too_short_time, Time, Result})
end;
{Time, Result} when Time > Upper ->
ct:fail({too_long_time, Time, Result});
{_, {error, timeout}} ->
ok;
{_, Result} ->
ct:fail({unexpected_result, Result})
end.
%% Try to obtain an unused IP address in the local network.
unused_ip() ->
{ok, Host} = inet:gethostname(),
{ok, Hent} = inet:gethostbyname(Host),
#hostent{h_addr_list=[{A, B, C, _D}|_]} = Hent,
%% Note: In our net, addresses below 16 are reserved for routers and
%% other strange creatures.
IP = unused_ip(A, B, C, 16),
io:format("we = ~p, unused_ip = ~p~n", [Hent, IP]),
IP.
unused_ip(255, 255, 255, 255) -> error;
unused_ip(255, B, C, D) -> unused_ip(1, B + 1, C, D);
unused_ip(A, 255, C, D) -> unused_ip(A, 1, C + 1, D);
unused_ip(A, B, 255, D) -> unused_ip(A, B, 1, D + 1);
unused_ip(A, B, C, D) ->
case inet:gethostbyaddr({A, B, C, D}) of
{ok, _} -> unused_ip(A + 1, B, C, D);
{error, _} -> {ok, {A, B, C, D}}
end.
ok({ok,V}) -> V;
ok(NotOk) ->
try throw(not_ok)
catch
throw:Thrown:Stacktrace ->
erlang:raise(
error, {Thrown, NotOk}, tl(Stacktrace))
end.
get_localaddr() ->
get_localaddr(["localhost", "localhost6", "ip6-localhost"]).
get_localaddr([]) ->
{error, localaddr_not_found};
get_localaddr([Localhost|Ls]) ->
case inet:getaddr(Localhost, inet6) of
{ok, LocalAddr} ->
io:format("~s ~p~n", [Localhost, LocalAddr]),
{ok, LocalAddr};
_ ->
get_localaddr(Ls)
end.
getsockfd() -> undefined.
closesockfd(_FD) -> undefined.
local_filename(Tag) ->
"/tmp/" ?MODULE_STRING "_" ++ os:getpid() ++ "_" ++ atom_to_list(Tag).
bin_filename(String) ->
unicode:characters_to_binary(String, file:native_name_encoding()).
delete_local_filenames() ->
_ =
[file:delete(F) ||
F <-
filelib:wildcard(
"/tmp/" ?MODULE_STRING "_" ++ os:getpid() ++ "_*")],
ok.
