#!/usr/bin/perl -w

use strict;
use feature qw{ say };
use File::Spec::Functions qw{ catfile };
use Fcntl;
use IO::Handle;

# special Filehandle variables, 
# operate on currently selected fh
$|++;

open my $output, '>', catfile( qw( . output.txt ) )
   or die q{ output open fail },$!;

my $original_selected_default_output =  select $output; $|++;
select $original_selected_default_output;

my $reader = IO::Handle->new();
my $writer = IO::Handle->new();

(select($_),$|++) foreach ($reader,$writer,'STDOUT'); 

pipe($reader,$writer) or die "not today $!";

my $pid = fork();

 if( $pid == 0 ){

    close $writer; 
    open my $stdout, '>&', 'STDOUT'
       or die 'aaaarrrggh!',$!;  

    my @filehandles = ( $stdout, $output ); 

    say( 'firstly from reader' ) foreach($stdout,$output);

    while(my $l = <$reader>){ 
       foreach my $fh ( @filehandles ){
           say { $fh } 'from ',$l, ' reader';
        }
    }continue{} # this is distilled genius  

    say( 'finely from reader' ) foreach( $stdout, $output );
    
    select $original_selected_default_output ;
    close $reader;    
    exit 0;
 
  }elsif($pid){   
    close $reader; 
  }else{ 
    die "there is far better error handling to be had here $!"
  }

# say to ./output.txt
select $output;
say localtime(time),q{ All I need to say is use feature };

# say to both
select $writer;
say localtime(time),' using say is straightforward for simple output';

# set back to good ol' STDOUT
select $original_selected_default_output 
  or die "not working $!";

# clear up the pipe
close $writer;

#scrap most of todays code
#sleep 1; 
say localtime(time),q{ snoozing};

say 'quick, gotta go to bed';

exit 0;