$|++;

if (my $pid = open(READ, "-|")) {
  my $line = <READ>;
  print "child said: [", $line, "]; ",time,"\n";
  $line = <READ>;
  print "child said: [", $line, "]; ",time,"\n";
} else {
  print "hello; ",time,"\n";
  sleep 2;
  print "how are you; ",time,"\n";
}