Here is a start for you. But I believe netcat will tell you if it can't connect. Why not run netcat thru some IPC. Or use a netcat written in Perl, see netcat.pl

#!/usr/bin/perl
use IO::Socket;

$addr = '192.168.0.1';
$port = '80';

$socket = eval {
  return IO::Socket::INET->new( Proto       => "tcp",
                                PeerAddr    => $addr,
                                PeerPort    => $port,
                                Reuse       => 1,
                                Timeout     => 10)
 or return undef;
};
if ($socket) {
  print "Port open\n";
  eval { return $socket->close; };
  return 1;
} else {
  print "Port NOT open\n";
  return undef;
}
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