diff options
Diffstat (limited to 'erts/preloaded/src/erlang.erl')
| -rw-r--r-- | erts/preloaded/src/erlang.erl | 306 |
1 files changed, 197 insertions, 109 deletions
diff --git a/erts/preloaded/src/erlang.erl b/erts/preloaded/src/erlang.erl index 063b9a1f26..edf79b8f75 100644 --- a/erts/preloaded/src/erlang.erl +++ b/erts/preloaded/src/erlang.erl @@ -1,7 +1,7 @@ %% %% %CopyrightBegin% %% -%% Copyright Ericsson AB 1996-2013. All Rights Reserved. +%% Copyright Ericsson AB 1996-2016. 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. @@ -71,7 +71,8 @@ | 'milli_seconds' | 'micro_seconds' | 'nano_seconds' - | 'native'. + | 'native' + | 'perf_counter'. %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% %% Native code BIF stubs and their types @@ -104,7 +105,9 @@ -export([garbage_collect/0, garbage_collect/1, garbage_collect/2]). -export([garbage_collect_message_area/0, get/0, get/1, get_keys/0, get_keys/1]). -export([get_module_info/1, get_stacktrace/0, group_leader/0]). --export([group_leader/2, halt/0, halt/1, halt/2, hash/2, hibernate/3]). +-export([group_leader/2]). +-export([halt/0, halt/1, halt/2, hash/2, + has_prepared_code_on_load/1, hibernate/3]). -export([insert_element/3]). -export([integer_to_binary/1, integer_to_list/1]). -export([iolist_size/1, iolist_to_binary/1]). @@ -227,27 +230,32 @@ send | 'receive' | procs | + ports | call | - silent | + arity | return_to | + silent | running | exiting | + running_procs | + running_ports | garbage_collection | timestamp | cpu_timestamp | monotonic_timestamp | strict_monotonic_timestamp | - arity | set_on_spawn | set_on_first_spawn | set_on_link | set_on_first_link | - {tracer, pid() | port()}. + {tracer, pid() | port()} | + {tracer, module(), term()}. -type trace_info_item_result() :: {traced, global | local | false | undefined} | {match_spec, trace_match_spec() | false | undefined} | {meta, pid() | port() | false | undefined | []} | + {meta, module(), term() } | {meta_match_spec, trace_match_spec() | false | undefined} | {call_count, non_neg_integer() | boolean() | undefined} | {call_time, [{pid(), non_neg_integer(), @@ -273,6 +281,7 @@ undefined | {flags, [trace_info_flag()]} | {tracer, pid() | port() | []} | + {tracer, module(), term()} | trace_info_item_result() | {all, [ trace_info_item_result() ] | false | undefined}. @@ -469,7 +478,7 @@ check_old_code(_Module) -> CheckResult :: boolean(). check_process_code(Pid, Module) -> try - erlang:check_process_code(Pid, Module, [{allow_gc, true}]) + erts_internal:check_process_code(Pid, Module, [{allow_gc, true}]) catch error:Error -> erlang:error(Error, [Pid, Module]) end. @@ -484,51 +493,11 @@ check_process_code(Pid, Module) -> CheckResult :: boolean() | aborted. check_process_code(Pid, Module, OptionList) -> try - {Async, AllowGC} = get_cpc_opts(OptionList, sync, true), - case Async of - {async, ReqId} -> - {priority, Prio} = erlang:process_info(erlang:self(), - priority), - erts_internal:request_system_task(Pid, - Prio, - {check_process_code, - ReqId, - Module, - AllowGC}), - async; - sync -> - case Pid == erlang:self() of - true -> - erts_internal:check_process_code(Module, - [{allow_gc, AllowGC}]); - false -> - {priority, Prio} = erlang:process_info(erlang:self(), - priority), - ReqId = erlang:make_ref(), - erts_internal:request_system_task(Pid, - Prio, - {check_process_code, - ReqId, - Module, - AllowGC}), - receive - {check_process_code, ReqId, CheckResult} -> - CheckResult - end - end - end + erts_internal:check_process_code(Pid, Module, OptionList) catch error:Error -> erlang:error(Error, [Pid, Module, OptionList]) end. -% gets async and allow_gc opts and verify valid option list -get_cpc_opts([{async, _ReqId} = AsyncTuple | Options], _OldAsync, AllowGC) -> - get_cpc_opts(Options, AsyncTuple, AllowGC); -get_cpc_opts([{allow_gc, AllowGC} | Options], Async, _OldAllowGC) -> - get_cpc_opts(Options, Async, AllowGC); -get_cpc_opts([], Async, AllowGC) -> - {Async, AllowGC}. - %% crc32/1 -spec erlang:crc32(Data) -> non_neg_integer() when Data :: iodata(). @@ -1011,14 +980,14 @@ group_leader(_GroupLeader, _Pid) -> %% Shadowed by erl_bif_types: erlang:halt/0 -spec halt() -> no_return(). halt() -> - erlang:nif_error(undefined). + erlang:halt(0, []). %% halt/1 %% Shadowed by erl_bif_types: erlang:halt/1 -spec halt(Status) -> no_return() when Status :: non_neg_integer() | 'abort' | string(). -halt(_Status) -> - erlang:nif_error(undefined). +halt(Status) -> + erlang:halt(Status, []). %% halt/2 %% Shadowed by erl_bif_types: erlang:halt/2 @@ -1036,6 +1005,12 @@ halt(_Status, _Options) -> hash(_Term, _Range) -> erlang:nif_error(undefined). +%% has_prepared_code_on_load/1 +-spec erlang:has_prepared_code_on_load(PreparedCode) -> boolean() when + PreparedCode :: binary(). +has_prepared_code_on_load(_PreparedCode) -> + erlang:nif_error(undefined). + %% hibernate/3 -spec erlang:hibernate(Module, Function, Args) -> no_return() when Module :: module(), @@ -1188,10 +1163,10 @@ map_size(_Map) -> erlang:nif_error(undefined). %% match_spec_test/3 --spec erlang:match_spec_test(P1, P2, P3) -> TestResult when - P1 :: [term()] | tuple(), - P2 :: term(), - P3 :: table | trace, +-spec erlang:match_spec_test(MatchAgainst, MatchSpec, Type) -> TestResult when + MatchAgainst :: [term()] | tuple(), + MatchSpec :: term(), + Type :: table | trace, TestResult :: {ok, term(), [return_trace], [ {error | warning, string()} ]} | {error, [ {error | warning, string()} ]}. match_spec_test(_P1, _P2, _P3) -> erlang:nif_error(undefined). @@ -1231,16 +1206,18 @@ module_loaded(_Module) -> erlang:nif_error(undefined). -type registered_name() :: atom(). - -type registered_process_identifier() :: registered_name() | {registered_name(), node()}. - -type monitor_process_identifier() :: pid() | registered_process_identifier(). +-type monitor_port_identifier() :: port() | registered_name(). %% monitor/2 --spec monitor(process, monitor_process_identifier()) -> MonitorRef when - MonitorRef :: reference(); - (time_offset, clock_service) -> MonitorRef when - MonitorRef :: reference(). +-spec monitor + (process, monitor_process_identifier()) -> MonitorRef + when MonitorRef :: reference(); + (port, monitor_port_identifier()) -> MonitorRef + when MonitorRef :: reference(); + (time_offset, clock_service) -> MonitorRef + when MonitorRef :: reference(). monitor(_Type, _Item) -> erlang:nif_error(undefined). @@ -1387,6 +1364,7 @@ convert_time_unit(Time, FromUnit, ToUnit) -> try FU = case FromUnit of native -> erts_internal:time_unit(); + perf_counter -> erts_internal:perf_counter_unit(); nano_seconds -> 1000*1000*1000; micro_seconds -> 1000*1000; milli_seconds -> 1000; @@ -1395,6 +1373,7 @@ convert_time_unit(Time, FromUnit, ToUnit) -> end, TU = case ToUnit of native -> erts_internal:time_unit(); + perf_counter -> erts_internal:perf_counter_unit(); nano_seconds -> 1000*1000*1000; micro_seconds -> 1000*1000; milli_seconds -> 1000; @@ -1473,8 +1452,16 @@ processes() -> %% purge_module/1 -spec purge_module(Module) -> true when Module :: atom(). -purge_module(_Module) -> - erlang:nif_error(undefined). +purge_module(Module) when erlang:is_atom(Module) -> + case erts_code_purger:purge(Module) of + {false, _} -> + erlang:error(badarg, [Module]); + {true, _} -> + true + end; +purge_module(Arg) -> + erlang:error(badarg, [Arg]). + %% put/2 -spec put(Key, Val) -> term() when @@ -1726,12 +1713,35 @@ time() -> erlang:nif_error(undefined). %% trace/3 --spec erlang:trace(PidSpec, How, FlagList) -> integer() when - PidSpec :: pid() | existing | new | all, +-spec erlang:trace(PidPortSpec, How, FlagList) -> integer() when + PidPortSpec :: pid() | port() + | all | processes | ports + | existing | existing_processes | existing_ports + | new | new_processes | new_ports, How :: boolean(), FlagList :: [trace_flag()]. -trace(_PidSpec, _How, _FlagList) -> - erlang:nif_error(undefined). +trace(PidPortSpec, How, FlagList) -> + %% Make sure that we have loaded the tracer module + case lists:keyfind(tracer, 1, FlagList) of + {tracer, Module, State} when erlang:is_atom(Module) -> + case erlang:module_loaded(Module) of + false -> + Module:enabled(trace_status, erlang:self(), State); + true -> + ok + end; + _ -> + ignore + end, + + try erts_internal:trace(PidPortSpec, How, FlagList) of + Res -> Res + catch E:R -> + {_, [_ | CST]} = erlang:process_info( + erlang:self(), current_stacktrace), + erlang:raise( + E, R, [{?MODULE, trace, [PidPortSpec, How, FlagList], []} | CST]) + end. %% trace_delivered/1 -spec erlang:trace_delivered(Tracee) -> Ref when @@ -1741,14 +1751,16 @@ trace_delivered(_Tracee) -> erlang:nif_error(undefined). %% trace_info/2 --spec erlang:trace_info(PidOrFunc, Item) -> Res when - PidOrFunc :: pid() | new | {Module, Function, Arity} | on_load, +-spec erlang:trace_info(PidPortFuncEvent, Item) -> Res when + PidPortFuncEvent :: pid() | port() | new | new_processes | new_ports + | {Module, Function, Arity} | on_load | send | 'receive', Module :: module(), Function :: atom(), Arity :: arity(), - Item :: flags | tracer | traced | match_spec | meta | meta_match_spec | call_count | call_time | all, + Item :: flags | tracer | traced | match_spec + | meta | meta_match_spec | call_count | call_time | all, Res :: trace_info_return(). -trace_info(_PidOrFunc, _Item) -> +trace_info(_PidPortFuncEvent, _Item) -> erlang:nif_error(undefined). %% trunc/1 @@ -2036,12 +2048,21 @@ nodes(_Arg) -> | eof | {parallelism, Boolean :: boolean()} | hide. -open_port(_PortName,_PortSettings) -> - erlang:nif_error(undefined). +open_port(PortName, PortSettings) -> + case case erts_internal:open_port(PortName, PortSettings) of + Ref when erlang:is_reference(Ref) -> receive {Ref, Res} -> Res end; + Res -> Res + end of + Port when erlang:is_port(Port) -> Port; + Error -> erlang:error(Error, [PortName, PortSettings]) + end. -type priority_level() :: low | normal | high | max. +-type message_queue_data() :: + off_heap | on_heap. + -spec process_flag(trap_exit, Boolean) -> OldBoolean when Boolean :: boolean(), OldBoolean :: boolean(); @@ -2054,6 +2075,12 @@ open_port(_PortName,_PortSettings) -> (min_bin_vheap_size, MinBinVHeapSize) -> OldMinBinVHeapSize when MinBinVHeapSize :: non_neg_integer(), OldMinBinVHeapSize :: non_neg_integer(); + (max_heap_size, MaxHeapSize) -> OldMaxHeapSize when + MaxHeapSize :: max_heap_size(), + OldMaxHeapSize :: max_heap_size(); + (message_queue_data, MQD) -> OldMQD when + MQD :: message_queue_data(), + OldMQD :: message_queue_data(); (priority, Level) -> OldLevel when Level :: priority_level(), OldLevel :: priority_level(); @@ -2080,6 +2107,7 @@ process_flag(_Flag, _Value) -> dictionary | error_handler | garbage_collection | + garbage_collection_info | group_leader | heap_size | initial_call | @@ -2092,6 +2120,7 @@ process_flag(_Flag, _Value) -> min_bin_vheap_size | monitored_by | monitors | + message_queue_data | priority | reductions | registered_name | @@ -2119,6 +2148,7 @@ process_flag(_Flag, _Value) -> {dictionary, Dictionary :: [{Key :: term(), Value :: term()}]} | {error_handler, Module :: module()} | {garbage_collection, GCInfo :: [{atom(),non_neg_integer()}]} | + {garbage_collection_info, GCInfo :: [{atom(),non_neg_integer()}]} | {group_leader, GroupLeader :: pid()} | {heap_size, Size :: non_neg_integer()} | {initial_call, mfa()} | @@ -2129,13 +2159,15 @@ process_flag(_Flag, _Value) -> {messages, MessageQueue :: [term()]} | {min_heap_size, MinHeapSize :: non_neg_integer()} | {min_bin_vheap_size, MinBinVHeapSize :: non_neg_integer()} | + {max_heap_size, MaxHeapSize :: max_heap_size()} | {monitored_by, Pids :: [pid()]} | {monitors, - Monitors :: [{process, Pid :: pid() | + Monitors :: [{process | port, Pid :: pid() | port() | {RegName :: atom(), Node :: node()}}]} | + {message_queue_data, MQD :: message_queue_data()} | {priority, Level :: priority_level()} | {reductions, Number :: non_neg_integer()} | - {registered_name, Atom :: atom()} | + {registered_name, [] | (Atom :: atom())} | {sequential_trace_token, [] | (SequentialTraceToken :: term())} | {stack_size, Size :: non_neg_integer()} | {status, Status :: exiting | garbage_collecting | waiting | running | runnable | suspended} | @@ -2212,6 +2244,7 @@ setelement(_Index, _Tuple1, _Value) -> | {priority, Level :: priority_level()} | {fullsweep_after, Number :: non_neg_integer()} | {min_heap_size, Size :: non_neg_integer()} + | {max_heap_size, Size :: max_heap_size()} | {min_bin_vheap_size, VSize :: non_neg_integer()}. spawn_opt(_Tuple) -> erlang:nif_error(undefined). @@ -2230,6 +2263,16 @@ spawn_opt(_Tuple) -> (io) -> {{input, Input}, {output, Output}} when Input :: non_neg_integer(), Output :: non_neg_integer(); + (microstate_accounting) -> [MSAcc_Thread] | undefined when + MSAcc_Thread :: #{ type := MSAcc_Thread_Type, + id := MSAcc_Thread_Id, + counters := MSAcc_Counters}, + MSAcc_Thread_Type :: scheduler | async | aux, + MSAcc_Thread_Id :: non_neg_integer(), + MSAcc_Counters :: #{ MSAcc_Thread_State => non_neg_integer() }, + MSAcc_Thread_State :: alloc | aux | bif | busy_wait | check_io | + emulator | ets | gc | gc_fullsweep | nif | + other | port | send | sleep | timers; (reductions) -> {Total_Reductions, Reductions_Since_Last_Call} when Total_Reductions :: non_neg_integer(), @@ -2284,6 +2327,9 @@ subtract(_,_) -> (fullsweep_after, Number) -> OldNumber when Number :: non_neg_integer(), OldNumber :: non_neg_integer(); + (microstate_accounting, Action) -> OldState when + Action :: true | false | reset, + OldState :: true | false; (min_heap_size, MinHeapSize) -> OldMinHeapSize when MinHeapSize :: non_neg_integer(), OldMinHeapSize :: non_neg_integer(); @@ -2291,9 +2337,12 @@ subtract(_,_) -> OldMinBinVHeapSize when MinBinVHeapSize :: non_neg_integer(), OldMinBinVHeapSize :: non_neg_integer(); + (max_heap_size, MaxHeapSize) -> OldMaxHeapSize when + MaxHeapSize :: max_heap_size(), + OldMaxHeapSize :: max_heap_size(); (multi_scheduling, BlockState) -> OldBlockState when - BlockState :: block | unblock, - OldBlockState :: block | unblock | enabled; + BlockState :: block | unblock | block_normal | unblock_normal, + OldBlockState :: blocked | disabled | enabled; (scheduler_bind_type, How) -> OldBindType when How :: scheduler_bind_type() | default_bind, OldBindType :: scheduler_bind_type(); @@ -2311,7 +2360,7 @@ subtract(_,_) -> OldState :: preliminary | final | volatile; %% These are deliberately not documented (internal_cpu_topology, term()) -> term(); - (sequential_tracer, pid() | port() | false) -> pid() | port() | false; + (sequential_tracer, pid() | port() | {module(), term()} | false) -> pid() | port() | false; (1,0) -> true. system_flag(_Flag, _Value) -> @@ -2342,29 +2391,63 @@ tl(_List) -> [{[term()] | '_' ,[term()],[term()]}]. -spec erlang:trace_pattern(MFA, MatchSpec) -> non_neg_integer() when - MFA :: trace_pattern_mfa(), + MFA :: trace_pattern_mfa() | send | 'receive', MatchSpec :: (MatchSpecList :: trace_match_spec()) | boolean() | restart | pause. -trace_pattern(_MFA, _MatchSpec) -> - erlang:nif_error(undefined). +trace_pattern(MFA, MatchSpec) -> + try erts_internal:trace_pattern(MFA, MatchSpec, []) of + Res -> Res + catch E:R -> + {_, [_ | CST]} = erlang:process_info( + erlang:self(), current_stacktrace), + erlang:raise( + E, R, [{?MODULE, trace_pattern, [MFA, MatchSpec], []} | CST]) + end. -type trace_pattern_flag() :: global | local | meta | {meta, Pid :: pid()} | + {meta, TracerModule :: module(), TracerState :: term()} | call_count | call_time. --spec erlang:trace_pattern(MFA, MatchSpec, FlagList) -> non_neg_integer() when +-spec erlang:trace_pattern(send, MatchSpec, []) -> non_neg_integer() when + MatchSpec :: (MatchSpecList :: trace_match_spec()) + | boolean(); + ('receive', MatchSpec, []) -> non_neg_integer() when + MatchSpec :: (MatchSpecList :: trace_match_spec()) + | boolean(); + (MFA, MatchSpec, FlagList) -> non_neg_integer() when MFA :: trace_pattern_mfa(), MatchSpec :: (MatchSpecList :: trace_match_spec()) | boolean() | restart | pause, FlagList :: [ trace_pattern_flag() ]. -trace_pattern(_MFA, _MatchSpec, _FlagList) -> - erlang:nif_error(undefined). +trace_pattern(MFA, MatchSpec, FlagList) -> + %% Make sure that we have loaded the tracer module + case lists:keyfind(meta, 1, FlagList) of + {meta, Module, State} when erlang:is_atom(Module) -> + case erlang:module_loaded(Module) of + false -> + Module:enabled(trace_status, erlang:self(), State); + true -> + ok + end; + _ -> + ignore + end, + + try erts_internal:trace_pattern(MFA, MatchSpec, FlagList) of + Res -> Res + catch E:R -> + {_, [_ | CST]} = erlang:process_info( + erlang:self(), current_stacktrace), + erlang:raise( + E, R, [{?MODULE, trace_pattern, [MFA, MatchSpec, FlagList], []} | CST]) + end. %% Shadowed by erl_bif_types: erlang:tuple_to_list/1 -spec tuple_to_list(Tuple) -> [term()] when @@ -2438,13 +2521,16 @@ tuple_to_list(_Tuple) -> logical_processors_available | logical_processors_online) -> unknown | pos_integer(); (machine) -> string(); + (max_heap_size) -> {max_heap_size, MaxHeapSize :: max_heap_size()}; + (message_queue_data) -> message_queue_data(); (min_heap_size) -> {min_heap_size, MinHeapSize :: pos_integer()}; (min_bin_vheap_size) -> {min_bin_vheap_size, MinBinVHeapSize :: pos_integer()}; (modified_timing_level) -> integer() | undefined; - (multi_scheduling) -> disabled | blocked | enabled; + (multi_scheduling) -> disabled | blocked | blocked_normal | enabled; (multi_scheduling_blockers) -> [Pid :: pid()]; (nif_version) -> string(); + (normal_multi_scheduling_blockers) -> [Pid :: pid()]; (otp_release) -> string(); (os_monotonic_time_source) -> [{atom(),term()}]; (os_system_time_source) -> [{atom(),term()}]; @@ -2494,6 +2580,7 @@ universaltime_to_localtime(_Universaltime) -> %%-------------------------------------------------------------------------- +%% Shadowed by erl_bif_types: erlang:apply/2 -spec apply(Fun, Args) -> term() when Fun :: function(), Args :: [term()]. @@ -2572,14 +2659,27 @@ spawn_monitor(M, F, A) when erlang:is_atom(M), spawn_monitor(M, F, A) -> erlang:error(badarg, [M,F,A]). + +-type max_heap_size() :: + Size :: non_neg_integer() + %% TODO change size => to := when -type maps support is finalized + | #{ size => non_neg_integer(), + kill => boolean(), + error_logger => boolean() }. + +-type spawn_opt_option() :: + link + | monitor + | {priority, Level :: priority_level()} + | {fullsweep_after, Number :: non_neg_integer()} + | {min_heap_size, Size :: non_neg_integer()} + | {min_bin_vheap_size, VSize :: non_neg_integer()} + | {max_heap_size, Size :: max_heap_size()} + | {message_queue_data, MQD :: message_queue_data()}. + -spec spawn_opt(Fun, Options) -> pid() | {pid(), reference()} when Fun :: function(), - Options :: [Option], - Option :: link | monitor - | {priority, Level :: priority_level()} - | {fullsweep_after, Number :: non_neg_integer()} - | {min_heap_size, Size :: non_neg_integer()} - | {min_bin_vheap_size, VSize :: non_neg_integer()}. + Options :: [spawn_opt_option()]. spawn_opt(F, O) when erlang:is_function(F) -> spawn_opt(erlang, apply, [F, []], O); spawn_opt({M,F}=MF, O) when erlang:is_atom(M), erlang:is_atom(F) -> @@ -2592,12 +2692,7 @@ spawn_opt(F, O) -> -spec spawn_opt(Node, Fun, Options) -> pid() | {pid(), reference()} when Node :: node(), Fun :: function(), - Options :: [Option], - Option :: link | monitor - | {priority, Level :: priority_level()} - | {fullsweep_after, Number :: non_neg_integer()} - | {min_heap_size, Size :: non_neg_integer()} - | {min_bin_vheap_size, VSize :: non_neg_integer()}. + Options :: [spawn_opt_option()]. spawn_opt(N, F, O) when N =:= erlang:node() -> spawn_opt(F, O); spawn_opt(N, F, O) when erlang:is_function(F) -> @@ -2684,12 +2779,7 @@ spawn_link(N,M,F,A) -> Module :: module(), Function :: atom(), Args :: [term()], - Options :: [Option], - Option :: link | monitor - | {priority, Level :: priority_level()} - | {fullsweep_after, Number :: non_neg_integer()} - | {min_heap_size, Size :: non_neg_integer()} - | {min_bin_vheap_size, VSize :: non_neg_integer()}. + Options :: [spawn_opt_option()]. spawn_opt(M, F, A, Opts) -> case catch erlang:spawn_opt({M,F,A,Opts}) of {'EXIT',{Reason,_}} -> @@ -2704,12 +2794,7 @@ spawn_opt(M, F, A, Opts) -> Module :: module(), Function :: atom(), Args :: [term()], - Options :: [Option], - Option :: link | monitor - | {priority, Level :: priority_level()} - | {fullsweep_after, Number :: non_neg_integer()} - | {min_heap_size, Size :: non_neg_integer()} - | {min_bin_vheap_size, VSize :: non_neg_integer()}. + Options :: [spawn_opt_option()]. spawn_opt(N, M, F, A, O) when N =:= erlang:node(), erlang:is_atom(M), erlang:is_atom(F), erlang:is_list(A), erlang:is_list(O) -> @@ -3004,6 +3089,9 @@ port_info(Port) -> (Port, monitors) -> {monitors, Monitors} | 'undefined' when Port :: port() | atom(), Monitors :: [{process, pid()}]; + (Port, monitored_by) -> {monitored_by, MonitoredBy} | 'undefined' when + Port :: port() | atom(), + MonitoredBy :: [pid()]; (Port, name) -> {name, Name} | 'undefined' when Port :: port() | atom(), Name :: string(); |