Re^4: Waiting for input, without sleep

Hrm. For some reason Peek keeps giving me "0" and it falls out if the while loop right away:

while($response = $sock->peek())
{
    if ($response ne '')
    {    
        #verify the data
        print "Server Response: $response\n";
        
        $response = (string2hex($response));
        print "Server Response: $response\n";
        last;
    }
    else
    {
        sleep 1;
        print "Waiting for a response!\n";
    }
}
[download]

Comment on Re^4: Waiting for input, without sleep Download Code

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Re^5: Waiting for input, without sleep by jrsimmon (Hermit) on Jun 30, 2009 at 16:28 UTC
You're using a string operator on a number in your if statement. Try changing `if($response ne ''){ ... }else{ ... }` [download] to `if($response > 0){ ... }else{ ... }` [download]	[reply] [d/l] [select]
Re^6: Waiting for input, without sleep by Trihedralguy (Pilgrim) on Jun 30, 2009 at 16:36 UTC
So the message I get back then is still 0? Should I still be using sysread?	[reply]
Re^7: Waiting for input, without sleep by jrsimmon (Hermit) on Jun 30, 2009 at 16:45 UTC
Yes, you use peek() to know whether or not it is time to read(). The difference between peek() and read() is that read() removes from the socket the data that was read, where peek() simply reports what is there without altering it. This allows you to peek() repeatedly until the full contents of a message are available, at which time you read() to retrieve the message and remove it from the socket buffer. Also, I think your syntax for peek() should look more like your syntax for sysread(...) (I'm not overly familiar with sockets in perl and you seem capable of tracking the details down, so I'll leave that to you.) I'd prefer the cpan module be more explicit about the arguments and return value, but evidently that's just me.	[reply]
Re^8: Waiting for input, without sleep by Trihedralguy (Pilgrim) on Jun 30, 2009 at 16:51 UTC