perl/prime.pl

   1 #!/usr/bin/perl
   2 # prime-pthread, courtesy of Tom Christiansen
   3
   4 use strict;
   5 use warnings;
   6
   7 use threads;
   8 use Thread::Queue;
   9
  10 my $stream = Thread::Queue->new();
  11 for my $i ( 3 .. 1000 ) {
  12     $stream->enqueue($i);
  13 }
  14 $stream->enqueue(undef);
  15
  16 threads->create(\&check_num, $stream, 2);
  17 $kid->join();
  18
  19 sub check_num {
  20     my ($upstream, $cur_prime) = @_;
  21     my $kid;
  22     my $downstream = Thread::Queue->new();
  23     while (my $num = $upstream->dequeue()) {
  24         next unless ($num % $cur_prime);
  25         if ($kid) {
  26             $downstream->enqueue($num);
  27         } else {
  28             print("Found prime $num\n");
  29             $kid = threads->create(\&check_num, $downstream, $num);
  30         }
  31     }
  32     if ($kid) {
  33         $downstream->enqueue(undef);
  34         $kid->join();
  35     }
  36 }