Hi, I hope that this is a really silly newbie question, revolving around a simple mistake. (: I'm trying to communicate with a data server, providing stock quotes and the like. I'm quite new to perl, and very new to socket programming, so I'm not entirely sure what I'm doing... I've been reading through the search results for a couple days, but I'm still stumped. The header of each packet is in binary, followed by a bunch of ASCII data, in the format: 1 byte ascii sync byte (character 002) 2 byte message size (including header) 1 byte data offset (header size) 1 byte message type (To logon, I'm to send hex value 0x4c) 4 byte sequence id number 2 byte protocol id (always 0) 2 byte version number (1) And then the ASCII data consisting of login and password information. I'm not sure if y'all will be able to help with this at all -- to many variables, I'm too lost... It might not even be a perl problem -- but I thought that if I posted the code someone might have some good advice. It complains that the message length is invalid -- am I not communicating the size correctly? Or am I doing something silly that makes the header much bigger than it should be? Thank you, and I'm sorry this is so involved... 
#!/usr/bin/perl -w
use IO::Socket;

$rsock = new IO::Socket::INET (PeerAddr => 'blah',
                               PeerPort=> 1234,
                               Proto    => 'tcp',
                              );
die "Remote socket could not be created: $!\n" unless $rsock;

$str[0]="\002";
$str[1] = unpack("B*", pack("N", 47));
$str[2] = unpack("B*", pack("N", 12));
$str[3] = unpack("B*", pack("N",76));
$str[4] = unpack("B*", pack("N", 1));
$str[5] = unpack("B*", pack("N", 0));
$str[6] = unpack("B*", pack("N", 1));
$header=join('',@str);
$header=$header."LOGON USERNAME=NAME PASSWORD=PASS\0";

print $rsock $header;
#syswrite($rsock,$header,47);
# Print, or syswrite? Neither seem to help...

while (<$rsock>) {
  last unless /\S/;
  chomp;
  print;
}
# Returns Error: Ileagle message size in header

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In reply to Socket Newbie (perl newbie, too...) by Sabacthani

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