#! /usr/bin/perl
use strict;
use IPC::Open2;

local *PIPE;
local *OUT;
my $pid = open(PIPE, "-|", "echo", "hi") or die "Can't echo: $!";
print "The pid of the echo command is: $pid";
<STDIN>;
open2(\*OUT, "<&PIPE", "perl", "-ne", "print uc")
  or die "open2 failed: $!";
print while <OUT>;