#!/usr/bin/perl -w
use strict;

my $childLimit = shift @ARGV; #get total number of children
my @pids = (); #array of pids of children

for(my $i = 0; $i < $childLimit; $i++)
{
    if( !( $pids[$i] = fork() ) )
    {
        # in the child
        callChildSub();

        exit(0); # exit from the child process IMPORTANT
    } 
}

foreach my $pid (@pids)
{
    waitpid $pid, 0;
}

sub callChildSub()
{
    print "I am the child with pid $$.\n";
}