erlang分布式入门（二）-UDP Server-Client

项目中有在UDP协议上提供的服务，需要对服务的性能进行测试和优化，便找了下使用erlang实现的udp的服务端和客户端。

 

1.udpServer.erl

-module(udpServer).
-export([start/0, client/1]).

start() ->
        spawn(fun() -> server(4000) end).

server(Port) ->
        {ok, Socket} = gen_udp:open(Port, [binary, {active, false}]),
        io:format("server opened socket:~p~n",[Socket]),
        loop(Socket).

loop(Socket) ->
        inet:setopts(Socket, [{active, once}]),
        receive
                {udp, Socket, Host, Port, Bin} ->
                        io:format("server received:~p~n",[Bin]),
                        gen_udp:send(Socket, Host, Port, Bin),
                        loop(Socket)
        end.

% Client code
client(N) ->
        {ok, Socket} = gen_udp:open(0, [binary]),
        io:format("client opened socket=~p~n",[Socket]),
        ok = gen_udp:send(Socket, "localhost", 4000, N),
        Value = receive
                                {udp, Socket, _, _, Bin} ->
                                        io:format("client received:~p~n",[Bin])
                        after 2000 ->
                                        0
                        end,
        gen_udp:close(Socket),
        Value.

 

2.在一个终端下启动服务器端

[root@centos-183 erlang-learn]# erl
Erlang R15B (erts-5.9) [source] [smp:2:2] [async-threads:0] [hipe] [kernel-poll:false]

Eshell V5.9  (abort with ^G)
1> c(udpServer).
{ok,udpServer}
2> udpServer:start().
<0.39.0>
server opened socket:#Port<0.2237>
server received:<<"Hello">>
3> 

 在服务端执行udpServer:start().  之后在另外一个终端下启动客户端

[root@centos-183 erlang-learn]# erl
Erlang R15B (erts-5.9) [source] [smp:2:2] [async-threads:0] [hipe] [kernel-poll:false]

Eshell V5.9  (abort with ^G)
1> udpServer:client(<<"Hello">>).
client opened socket=#Port<0.608>
client received:<<"Hello">>
ok
2>