sockets - limitation of the reception buffer -

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i established connection client way:

gen_tcp:listen(1234,[binary,{packet,0},{reuseaddr,true},{active,false},{recbuf,2048}]).

this code performs message processing:

loop(socket)->     inet:setops(socket,[{active,once}],     receive         {tcp,socket,data}->             handle(data),             loop(socket);         {pid,cmd}->             gen_tcp:send(socket,cmd),             loop(socket);         {tcp_close,socket}->             % ... end.

my os windows. when size of message 1024 bytes, lose bytes in data. server sends ack + fin client.

i believe erlang limited 1024 bytes, therefore defined recbuf.

where problem is: erlang, windows, hardware?

thanks.

you may setting receive buffer far small. erlang isn't limited 1024 byte buffer. can check doing following in shell:

{ok, s} = gen_tcp:connect("www.google.com", 80, [{active,false}]), o = inet:getopts(s, [recbuf]), gen_tcp:close(s), o.

on mac os x default receive buffer size of 512kb.

with {packet, 0} parsing, you'll receive tcp data in whatever chunks network stack chooses send in, have message boundary parsing , buffering yourself. have reliable way check message boundaries in wire protocol? if so, receive tcp data , append buffer variable until have complete message. call handle on complete message , remove complete message buffer before continuing.

we more if gave information on client , protocol in use.


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