UDP socket connect.

leonidlm has asked for the wisdom of the Perl Monks concerning the following question:

Hi all, I wrote the following UDP "pooler" code:

sub sampleNode
{
    my ($msg, $peerAddr, $eTime) = @_;
    my $bol = 0;
    
    print "Sending the message to the server for node $msg...\n";
    $MySocket = new IO::Socket::INET->new(    PeerPort => 6060,
                            Proto => 'udp',
                            PeerAddr => $peerAddr,
                            );
    ioctl($MySocket, 0x8004667e, pack("I", 1));
    
    $MySocket->send($msg);
    while((time() < $eTime) && (!$bol))
    {
        #print "time: " . time() . ", threshold: $eTime\n";

        $MySocket->recv($text,128);
        print $text;
        if($text =~ /OK/)
        {
            print "Received ok response: $text";
            $bol = 1;
        }
    }
    return $bol;
}
[download]

My question is very simple: What the following line does? ioctl($MySocket, 0x8004667e, pack("I", 1)); Whotout this line the timeout just won't work, it freezes on $MySocket->recv($text,128); I just found it and paste it in my code and now it is working! I really want to fully understand that. Thanks all!

Comment on UDP socket connect. Download Code

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Re: UDP socket connect. by glide (Pilgrim) on Jan 31, 2008 at 11:28 UTC
That line it's to get a non-blocking IO. You can read more about it in Non-blocking socket read on Windows.	[reply]
Re^2: UDP socket connect. by leonidlm (Pilgrim) on Jan 31, 2008 at 11:49 UTC
Thx. Can you explain in more detail about this command? 1. each parameter 2. Why I can't use something from the Sockets module? If I remember right there is a blocking parameter in the New method. 3. Why for Windows? Thx, and sorry for the bulk of quastions :)	[reply]
Re^3: UDP socket connect. by glide (Pilgrim) on Jan 31, 2008 at 14:29 UTC
1 for the ioctl follow the link for the code, 0x8004667e, see in Re^2: Non-blocking socket read on Windows apparently the ioctl expect a reference as a parameter. Probably you can replace the pack by `my $nonblocking = 1; ioctl($self, 0x8004667e, \$nonblocking);` [download] 2 Yes, the option (Blocking) is in the IO::Socket::INET. Try it, and remove the ioctl line. 3 Aren't you using windows? :-) When working with sockets, you can't entirely ignore the platform, some time you have to adapt the code (options) to the platform.	[reply] [d/l]
Re^4: UDP socket connect. by leonidlm (Pilgrim) on Jan 31, 2008 at 14:56 UTC
Re: UDP socket connect. by glide (Pilgrim) on Jan 31, 2008 at 11:12 UTC
Hi, It's very difficult to read your question. Please, read the Writeup Formatting Tips, and update the post. update: thanks	[reply]