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<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'>There are three ways to receive data using
gen_tcp, depending on which mode you’ve selected. The gen_tcp:recv may be
used only if your socket has been opened with additional option flag {active,
false} – which means that you do not want to receive unsolicited traffic.
, thus, just change your line from:<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'> case gen_tcp:connect("127.0.0.1", Port,
[list,{packet,0}]) of<br>
<br>
<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'>to <o:p></o:p></span></font></p>
<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'>case gen_tcp:connect("127.0.0.1", Port, [list,{packet,0},
{active, false}]) of<br>
<br>
</span></font><font size=2 color=navy face=Arial><span style='font-size:10.0pt;
font-family:Arial;color:navy'><o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'>and the code should work.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'>The error message is a bit misleading, but
if you call gen_tcp:recv on a socket that does not contain {active, fase},
gen_tcp:recv shall return {error,einval}, which will in turn cause function_clause
error message.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'>V.<o:p></o:p></span></font></p>
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<p class=MsoNormal><b><font size=2 face=Tahoma><span style='font-size:10.0pt;
font-family:Tahoma;font-weight:bold'>From:</span></font></b><font size=2
face=Tahoma><span style='font-size:10.0pt;font-family:Tahoma'>
erlang-questions-bounces@erlang.org
[mailto:erlang-questions-bounces@erlang.org] <b><span style='font-weight:bold'>On
Behalf Of </span></b>Shelby Ramsey<br>
<b><span style='font-weight:bold'>Sent:</span></b> 06 March 2009 04:22 AM<br>
<b><span style='font-weight:bold'>To:</span></b> erlang-questions@erlang.org<br>
<b><span style='font-weight:bold'>Subject:</span></b> [erlang-questions] Noob
Question ...</span></font><o:p></o:p></p>
</div>
<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'>Hello! <br>
<br>
I'm trying to become an erlang convert (from Python) and I do mostly network
programming.<br>
<br>
So I wrote up this little tidbit:<br>
<br>
-module(test).<br>
-export([client/1]).<br>
<br>
client([Port]) -><br>
case gen_tcp:connect("127.0.0.1", Port,
[list,{packet,0}]) of<br>
{ok, Socket} -><br>
gen_tcp:send(Socket,"auth iltd!dy69?\r\n\r\n"),<br>
gen_tcp:send(Socket,"event plain text\r\n\r\n"),<br>
loop(Socket);<br>
{error, Reason} -><br>
print_stuff([Reason]),<br>
ok<br>
end.<br>
<br>
loop(Socket) -><br>
case gen_tcp:recv(Socket, 0) of<br>
{ok, Data} -><br>
print_stuff([Data]),<br>
loop(Socket);<br>
{error, closed} -><br>
ok<br>
end.<br>
<br>
print_stuff([Text]) -><br>
io:format("~w", [Text]).<br>
<br>
It compiles ... but when I run ... well ... it spits this:<br>
<br>
=ERROR REPORT==== 5-Mar-2009::20:19:27 ===<br>
Error in process <0.30.0> with exit value:
{function_clause,[{test,client,[8021]},{erl_eval,do_apply,5},{shell,exprs,6},{shell,eval_loop,3}]}<br>
<br>
** exited: {function_clause,[{test,client,[8021]},<br>
{erl_eval,do_apply,5},<br>
{shell,exprs,6},<br>
{shell,eval_loop,3}]} **<br>
<br>
<br>
So what did I hose up? And more importantly ... where is some
documentation re: how to debug the "error report".<br>
<br>
Thanks for any assistance!<br>
<br>
SDR<o:p></o:p></span></font></p>
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