I have a crude Erlang-to-Golang port example, passing data from Erlang to Golang and echoing the response.

Problem is the amount of data I can transfer seems to be limited to 2^8 bytes (see below). I thought the problem was probably on the Golang side (not creating a big enough buffer) but replacing bufio.NewReader with bufio.NewReaderSize didn't work. So am now thinking the problem is maybe on the Erlang side.

What do I need to do to increase the buffer size / be able to echo a message larger than 2^8 bytes ?

TIA

justin@justin-ThinkPad-X240:~/work/erlang_golang_port$ erl -pa ebin
Erlang/OTP 17 [erts-6.4.1] [source] [64-bit] [smp:4:4] [async-threads:10] [kernel-poll:false]

Eshell V6.4.1  (abort with ^G)
1> port:start("./echo").
<0.35.0>
2> port:ping(65000).
65000
3> port:ping(66000).
** exception error: bad argument
     in function  port:call_port/1 (port.erl, line 20)
4> port:start("./echo").
<0.40.0>
5> port:ping(66000).    
65536

Go

package main

import (
    "bufio"
    "os"
)

const Delimiter = '
'

func main() {
    // reader := bufio:NewReader(os.Stdin)
    reader := bufio.NewReaderSize(os.Stdin, 1677216) // 2**24;
    bytes, _ := reader.ReadBytes(Delimiter)
    os.Stdout.Write(bytes[:len(bytes)-1])
}

Erlang

-module(port).

-export([start/1, stop/0, init/1]).

-export([ping/1]).

-define(DELIMITER, [10]).

start(ExtPrg) ->
    spawn(?MODULE, init, [ExtPrg]).

stop() ->
    myname ! stop.

ping(N) ->
    Msg=[round(65+26*random:uniform()) || _ <- lists:seq(1, N)],
    call_port(Msg).

call_port(Msg) ->
    myname ! {call, self(), Msg},
    receive
    {myname, Result} ->
        length(Result)
    end.

init(ExtPrg) ->
    register(myname, self()),
    process_flag(trap_exit, true),
    Port = open_port({spawn, ExtPrg}, []),
    loop(Port).

loop(Port) ->
    receive
    {call, Caller, Msg} ->
        Port ! {self(), {command, Msg++?DELIMITER}},
        receive
        {Port, {data, Data}} ->
            Caller ! {myname, Data}
        end,
        loop(Port);
    stop ->
        Port ! {self(), close},
        receive
        {Port, closed} ->
            exit(normal)
        end;
    {'EXIT', Port, _Reason} ->
        exit(port_terminated)
    end.

erlang环境搭配好IDEA ,怎么使用？我点击run老是报错

阳光温暖

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