use strict;
use warnings;

# ---- add this stub to the start of your program ----
use IO::File;
use IO::Capture::Stdout;

our $capture;
BEGIN{
    $capture = IO::Capture::Stdout->new();
    $capture->start();
}

END{
  $capture->stop();
  my $f = new IO::File "results.txt", "w" or die "Can not create file"
+;
  while (defined ($_ = $capture->read())) {
    print $f "$_";
    print "$_";
  }
}

# ---- your stuff here ----
print "Test Line One\n";
print "Test Line Two\n";
print "";
print "Test Line Three\n";
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Is it just me, or does IO::Capture seem like a stupid idea?

You can open a file for output and print to that outfile.

  open (MYOUTFILE, ">outfile.txt") or die "Can't create outfile: $!";

    # Other code

    print MYOUTFILE "$A,$B,n/a\n" if $i==0;
    print STDOUT "$A,$B,n/a\n" if $i==0;

    # Other code

  close MYOUTFILE;
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or

   if ($i==0){
      print MYOUTFILE "$A,$B,n/a\n";
      print STDOUT "$A,$B,n/a\n";
    }
[download]

There are variations on this and you can include screen output, append to files, and more. Your best bet is to read up on filehandles and open and print.

Resources

• Open
• Print
• Perl FAQ 5 on I/O File Handles, Formats, etc.

Update: Closed off some tags that messed up the code and picked up some dropped end tags.