sub gets1 {
  $| = 1;
  $ii = "";
  $i = 0;
  while ($n < 10) {
    { lock($n);
    $n++; }
    $ii .= $n;
    #print $ii . "\n";
    $i++;
  }
  print $i, "\n";
}

10
0
0
0
0
0
0
0
0
0
0

#!/usr/bin/perl
use threads;
use threads::shared;
my $n : shared;

$a = gets();
print $_, "\n" for @$a;
#print $a . "\n";

sub gets {
  $thr = 10;
  $n = 0;
  for(0..$thr) {
    $trl[$_] = threads->create(\&gets1);
  }
  for(0..$thr) {
    $res[$_] = $trl[$_]->join;
  }
  sub gets1 {
    $| = 1;
    $ii = "";
    while ($n < 10) {
      { lock($n);
      $n++; }
      $ii .= $n;
      #print $ii . "\n";
    }
    #print $ii, "\n";
    return $ii;
  }
  return \@res;
}

$a = gets();
@b = unpack 'C*', $a->[0];
$_ += 2 for @b;
print pack 'C*', @b;