Hi, Monks

I have very strange problem today. I run some code which works in the past but now it did't fork as i expect.

#!/usr/bin/perl

use strict;
use warnings;

my %pids;

my @chunk_indixes = find_chunk_indixes( 100, 10 );

foreach my $thread_id ( 0 .. 9 ) {
    
    if ( my $pid = fork() ) {

       $pids{$pid}++;
    }
    else {

        my $start = $chunk_indixes[$thread_id]->[0];
        my $end = $chunk_indixes[$thread_id]->[1];
        
        print "[$start, $end]\n";
        
    sleep(10);

        exit;
    }

    while (%pids) {

       my $pid = waitpid( -1, 0 );
       delete $pids{$pid};
    }
}

sub find_chunk_indixes {
    
    my ( $total_size, $number_of_chunks ) = @_;
    
    my @result;
    
    my $small_chunk = int( $total_size / $number_of_chunks );
    my $oversized_count = $total_size % $number_of_chunks;
    
    my @chunk_sizes =  ( ( 1 + $small_chunk ) x ($oversized_count), ($
+small_chunk) x ( $number_of_chunks - $oversized_count ) );
    
    my $current_position = 0;
    
    foreach my $chunk_size (@chunk_sizes) {
        
        push @result, [ $current_position, $current_position + $chunk_
+size - 1 ];
        $current_position += $chunk_size;
    }
    
    return @result;
}

[download]

I expect it forks 10 process at same time and prints 

0, 9
10, 19
20, 29
30, 39
40, 49
50, 59
60, 69
70, 79
80, 89
90, 99
at same moment but it prints only one range, wait for ten second and prints another range and so one.

Process explorer shows me only two process of this script. Also i test this on Windows XP in Linux -- same result.

Can you show me what's wrong with this program?

Thanks.
Roman

In reply to fork() not working as expected by Gangabass

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