I'd say that fork() does work sometimes under
ActiveState Perl, but the problems start as soon as you share too
much stuff (like, for example, sockets) between the two processes.
There are some ways around your specific problem, for example,
you could use a perlfunc:select-based client that checks
whether there is something to read or write. I've done so
with a server here, but the concept can be reused for a
client as well.
As for another route, if you have control
over the server as well, you might want to change your protocol
to HTTP or some other protocol that sends the size of the response
within the response header.
perl -MHTTP::Daemon -MHTTP::Response -MLWP::Simple -e ' ; # The
$d = new HTTP::Daemon and fork and getprint $d->url and exit;#spider
($c = $d->accept())->get_request(); $c->send_response( new #in the
HTTP::Response(200,$_,$_,qq(Just another Perl hacker\n))); ' # web
