I was playing with this script and all I want to happen is to make 2 child processes run at the same time. After they are finish, another 2 child processes will run again. What is happening is that all the child processes are running at the same time and in the end, the parents waits for all of them to finish.

This can simply be done in Parallel::ForkManager but I cannot download and install it in our system for security reason. 
#!/usr/bin/perl
use strict;

my @array = qw(a b c d e f g h);
my @childs;

for (1 .. 10) {
    my $pid = fork();
    if ($pid) {
        push (@childs, $pid);
    }
    else ($pid == 0) {
        print "@array\n\n";
        sleep 10;
        exit (0);
    }

    print "Running another child process - $pid.\n";
}

print "All child processes have been ran.\n";
print "@childs\n";

foreach (@childs) {   
    waitpid ($_, 0);
}

print "All child processes are finished.\n";

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In reply to Simple Parallel Processing Question by bichonfrise74

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