#!/usr/bin/perl -w
use strict;
use IPC::Run qw[  start pump finish timeout ];
use constant true   => (1==1);
use constant false  => (1==0);

my $N_instances = shift;
my (@in,@out,@err,@handle,@finished);
my $done;

foreach my $i ( 1 .. $N_instances)
  {
    $finished[$i]= false;
    $handle[$i]  = start \@ARGV, \$in[$i], \$out[$i], \$err[$i] ;    
  }

while (!$done)
  {
    $done   = true;
    foreach my $i ( 1 .. $N_instances)
     {
        $done   &= $finished[$i];
        next if ($finished[$i]);
        if ($handle[$i]->pumpable)
           {
             $handle[$i]->pump_nb;
             printf "O[%i]: %s",$i,$out[$i] if ($out[$i]);
             printf "E[%i]: %s",$i,$err[$i] if ($err[$i]);
             $out[$i] = "";
             $err[$i] = "";
           }
          else
           {
             $finished[$i] = true;
             $handle[$i]->finish;
           }
     }
  }