my $pwm_count_hash = undef;
PWM:
for my $pwm (@ciona_pwm_array) {
    $pm->start and next PWM;
    ($pwm_count_hash->{$pwm}) = count_pwm_num($pwm,$seq_1,$seq_2);
    #print $pwm,"\t",$pwm_count_hash->{$pwm},"\n";
    $pm->finish;
}

$pm->wait_all_children;

foreach my $id (keys %{$pwm_count_hash}) {
      print $id,"\t",$pwm_count_hash->{$id},"\n";
      # no printing here!
}

[download]

I declared a hash reference ($pwm_count_hash) outside of parallel processing fork.However, when terminating all child process, this value ($pwm_count_hash) was still undefined. The foreach loop after forking processing lead to no result. I expect that this value had been defined after each child process.

I think this may be related to child-parent talk. But I have a little knowledge of it. Please let me know how to initialize $pwm_count_hash in the child process.

In reply to value uninitilized when using Parallel::ForkManager module by plagent

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