Why sysread() + select() only read the first line?

[perlmonks12]

Hi I'm using sockets and I'm using to see when there is data to be read, I'm using in this way.

ready = $select->can_read(5);

if (! scalar(@ready)) {

        print "Timed out\n";

} else {

        $sock = $ready[0];

       if (! sysread($ready[0], $msg, 512)) {

                        print "recv failed :$!\n";

        } else {

                    print "$msg";

        }

}

The code tell me when there is something to be read and it read it and print on the screen. However, it just print the first line, while the answer is much bigger, the first line is like 45 chars + \r\n\r\n and then it has more 300 bytes or so, that are never displayed. However, if I start tcpdump I can see this data coming, but never displayed. What I'm doing wrong? Thanks.

[ikegami]

Suffering form buffering? Try adding $|=1;

[tye]

My guess is that you are suffering from buffering (on STDOUT -- sockets aren't buffered). Try adding the following at the top of your code:

$|= 1;

[choroba]

You can search for select line and find poorly documented behaviour of readline() and IO::Select.

[perlmonks12]

Thanks all, it solved the problem.