Hi Guys,

i'm trying to learn erlang :-) since it seems like Erlang loves small messages like quotes - and loves IP/Sockets. But i'm a TOTAL newbie into erlang - and took me a while to get feed up and get data out.

So I thought I would share - and would love if anyone else in the same boat would share too.

So here is a short code that 1. starts IQFeed, 2. Connects to Socket, 3 Retrieves a packet or two from port 5009 and outputs them to the console.

:code!!
%%%file_comment
-module(iqfeed_start).


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

start() ->
open_port({spawn,"IQConnect.exe -product IQFEED_DEMO -version 1.0.0.0"}, []),
timer:sleep(1000). %open IQfeed and then wait for login etc


client(PortNo) ->
start(), %calls the start of IQConnect - remove this
{ok,Sock} = gen_tcp:connect("localhost", PortNo,[binary, {active,false}]), %open a socket connection
io:format("Connected to sock:~p ~n",[Sock]),
%%%gen_tcp:send(Sock,Message),
{ok,A}=gen_tcp:recv(Sock, 0), %receive what is waiting for us like "S,KEY etc"
io:format("~p ~n", [A]), % print it to console
gen_tcp:send(Sock,"wMSFT\r\n"), %ask for a Microsoft quote
io:format("command sent~n"),
Bx = gen_tcp:recv(Sock,0), %receive packet
io:format("~p ~n", [Bx]),
io:format("waiting for next server packet~n"),
C = gen_tcp:recv(Sock,0), %get next packet - if market not active this will show the 1 minute timer
io:format("~p ~n", [C]), % print it.
gen_tcp:close(Sock). %actually closes IQFeed - make it a comment for tests!


you start it by compiling the iqfeed_start.erl "c(iqfeed_start) from Erlang console. Then you can call it by writing "iqfeed_start:client(5009)." [enter] - where 5009 is the port number.

My todo list: Find a way to detect if IQFeed is already running (like fire a socket connect request)
Edited by klarsen on Jun 23, 2010 at 01:00 AM

Here's how it can be done in Perl.

#!/usr/bin/perl

use POE qw(Component::Client::TCPMulti);

system("/path/to/IQFeed/iqconnect.exe -product DEMO -version 1.1 &");
sleep 15;

my ($level1,$feed);

POE::Component::Client::TCPMulti->new(
InputEvent => sub {
print "From server: $_[ARG0]\n";
},
SuccessEvent => sub {
if ($_[ARG2] == 5009) {
$level1 = $_[ARG4];
$_[KERNEL]->yield(send => $level1, "wGOOG\r\n");
} elsif ($_[ARG2] == 9100) {
$feed = $_[ARG4];
$_[KERNEL]->yield(send => $feed, "HTD,MO1018U19,3\r\n");
}
},
inline_states => {
_start => sub {
$_[KERNEL]->yield(connect => '127.0.0.1', $_) for (5009, 9100);
},
}
);