Hello,

Once again I call on your help because I obviously don't really understand forking yet, although I have been reading up :-/

In the script below, there is something I want to do after sending off the children within the loop. But for some reason, everything after $fork_manager->finish never happens, and I don't understand why. I thought maybe the problem was the "... and next" at the start of the fork, because I've had problems with that in subs before. However, at the time, I enclosed the block in an extra {...}, and it worked. That doesn't help here.

use strict;
use warnings;
use diagnostics -verbose;
use Parallel::ForkManager;

my @array = ("") x 56;

my $fork_manager = new Parallel::ForkManager(16);
my $check = 0;

for my $val (@array) {
    
    $fork_manager->start and next;
    $check++;
    
    $fork_manager->finish; # Terminates the child process
    
    print "Hello?\n";
    
#    $fork_manager->start and next;
#    $check++;
#    $fork_manager->finish;
}
print "End: " . $check . "\n";

[download]

In addition, what I want to do relies on the processes within that iteration of the loop being done. I thought of using $fork_manager->wait_all_children, but doesn't that mean that ALL processes must be done, e.g. I could use it only outside the loop?

And then finally, there is one thing I am not sure about Fork::Manager's documentation: What if after the 1st bunch of processes in the loop, I want to start so more? Can I use the same object or should I create a new one? The documentation does contain a note about managing a set of subprocesses within the 1st one, but that's different from what I want to do here (I think).

I would gladly be enlightened :-)

In reply to Problem with [mod://Fork::Manager] by Anonymous Monk

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