Have you tried getting the script to write the file to disk

Yes

can this file be retrieved by the clients correctly?

Yes, I've written that file to the /tmp-Dir, copied it to the HTTPD-root-directory accessed it directly and could download it just fine.

have you tried having the script simultaniously write a copy of the file and return it to the client?

No, I am using the following code:

  my $tar = Archive::Tar->new;
  # ...
  # in a loop:
  $tar->add_files("$filename");
  # ...
  my $data = $tar->write();
  print $q->header(-type => 'application/octet-stream',
                   -attachment => "edi.tar");
  print $data;
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