open my $oldin, '<&', \*STDIN or die $!;

pipe my($r), my ($w) or die $!;
open STDIN, '<&', $r or die $!;

my $wh = FdGetOsFHandle(fileno $w);
SetHandleInformation($wh, HANDLE_FLAG_INHERIT, 0);

my $pid = system 1, 'perl -ne print';
print "pid: $pid\n";

close STDIN or die $!;
open STDIN, '<&', $oldin;

close $r or die $!;
print {$w} "hello world! ($_)\n" for 0..9;
close $w or die $!;

print "waiting for slave process\n";
waitpid $pid, 0 or die $!
[download]