You can just use a series of piped opens, and stuff their outputs into a hash. Here is a simple example. Instead of the while loop for reading output, you could make an IO::Select loop to read all the filehandles delivering your output. You can also specify different commands, by putting that into a hash too, instead of $cmd, you could have @cmds. 
#!/usr/bin/perl
use warnings;
use strict;

my %pids;

my @to_be_processed = (1..20);

my $cmd = 'echo';

foreach my $p (@to_be_processed){ 
 
#   untested way of changing command for each fork
 #   $pids{$p}{'cmd'} = shift @cmds, 
 #  $pids{$p}{'pid'} = open($pids{$p}{'fh'}, "  $pids{$p}{'cmd'}    $p
+ 2>&1 |");

# simpler example 
 $pids{$p}{'pid'} = open($pids{$p}{'fh'}, "$cmd $p 2>&1 |");
}


# can alternatively use an IO::Select object here to collect
# data from filehandles
foreach my $key(keys %pids){ 
  my $fh = $pids{$key}{'fh'};
  while (<$fh>){
    print $_;
    #stuff data here into a return hash
   }
}

# prevent zombies
foreach my $key(keys %pids){
   waitpid($pids{$key}, 1);
}

print "done\n";

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I'm not really a human, but I play one on earth.
Old Perl Programmer Haiku ................... flash japh

In reply to Re: parallel forks by zentara
in thread parallel forks by networker2149

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