#!/usr/bin/perl
use 5.018;
use strict;
use warnings;

my $pid = open (my $ARTICLE, "-|", "caesar") or die "Can't start caesar: $!\n$^E";

my $read = <$ARTICLE>;
say "[$read][$pid]";
##</code><code>##

perl pipe.pl
'caesar' is not recognized as an internal or external command,
operable program or batch file.
Use of uninitialized value $read in concatenation (.) or string at pipe.pl line 9.
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