I don't quite understand how forking your script will permit it to run on multiple boxes. Multiple CPU's, OK, but how do you cause it to run on another system? What you are describing is inconsistent what what you are asking and your sample code.

If you're asking how to keep 20 child processes active at any given time, keep track of them and use waitpid to see how many are gone: 

use POSIX ':sys_wait_h';

my $max_children = 20;
my $cur_children = 0;

$SIG{CHLD} = sub {
   $cur_children-- while waitpid(-1, &WNOHANG) != -1;
   &spawn_children;
}

sub spawn_children {
   while ($cur_children < $max_children) {
      my $pid = fork;
      die "fork: $!" unless defined $pid;
      &child_process if !$pid;
      $cur_children++;
   }
}

sub child_process {
   # what the kid does
   exit 0;   # important
}

&spawn_children;

[download]
But like I said, this makes no sense with respects to processes running on other systems. You may have to give us more information if this doesn't help you.

In reply to Re: controling the num of fork sessions by Fastolfe
in thread controling the num of fork sessions by Anonymous Monk

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