Hello

Is CRLF defined anywhere in your program? I can see that this is the source of trouble since you are chopping the EOL char and placing CRLF in its place. I tried this and it works as advertized:

use IO::Socket;
use constant CRLF => "\r\n";##### Add This
my $quit = 0;
my $port = 12345;
my $socket = IO::Socket::INET->new(    Listen        => 20,
                    LocalPort    => $port,
                    Timeout        => 5, #60 * 60,
                    Reuse        => 1)
or die "No socket: $!";

warn "listening on port $port...\n";

while ( !$quit ) {
    next unless my $session = $socket->accept;
    my $peer = gethostbyaddr($session->peeraddr,AF_INET)
            || $session->peerhost;
    my $port = $session->peerport;
    warn "Connection from [$peer,$port]\n";
    while(<$session>) {                     #BLOCKS HERE
        $bytes{'in'} += length($_);
        chomp;
        my $msg_out = $_ . CRLF;
        $session->print($msg_out);
        print $msg_out;
        $bytes{'out'} += length($msg_out);
    }
    warn "Connection from [$peer,$port] finished\n";
    close $session;
}
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Aziz,,,