dear perl monks.

i am somewhat of a perl beginner, and over the last few months have grown to love the language. As an attempt to learn to use various modules, i have written the following perl script. It is the beginnings of a very basic irc client.

the whole script and the configuration file

##########
#this is the bit that bugs out, afaik
##########

#enter select group read wait loop
my @ready_sockets;
while (@ready_sockets = $select_group->can_read) {
    
    #for each socket.....
    foreach my $sock (@ready_sockets) {
        
        #pull data from the socket
        my $data = <$sock>;
        
        #if the data is null, socket is closed
        if (!($data)) {
            print "socket closed\n" if $debug;
            #pull it out of the select group
            $select_group->remove($sock);
            $sock->close;
            return;
        }
        
        print "socket replied: $data" if $debug;
        
        
        if (substr($data,0,4) eq "PING") {
            print "pong" . substr($data,4);
            print $sock "PONG" . substr($data,4);
        }
        
    }
}
[download]

However, the script seems to have a problem that i cannot solve. when connecting to the irc server, the script correctly receives the first few lines, and then seems to ignore the data on the socket for a random amount of time. Oddly, it always pauses at the same point on each server, but it is a different point on each server. this leads the connection to time out.

it would appear that after reading the first few lines, the $select_group->can_read is not recognising data ready for reading on the socket. I do not know why.

so far i have tried the following to solve this problem:-

• setting autoflush on and off, with no result.
• setting $| on and off, with no result.
• setting $/ to various line endings (\010,\013\010), with no result.
• re-writing the entire thing to use the Event module, with no result (it gives exactly the same response).
• setting the socket to blocking and non-blocking mode, with no result

could anyone shed any light on this? i have been working on this all day and can see no reason at all why it should behave in this way. any help would be appreciated.

thankyou in advance.

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