I used Data::Dumper on the "filehandle" returned to me by use of libnet's Net::FTP to issue a RETR FTP command, which returns a filehandle to a remote file.

if you dump what Net::FTP returns here it is:

  {
    $fh = $self->_do_ftp_cmd("retr", $file);

    die("File unavailable: $file") unless $fh;
    }
    use Data::Dumper;
    warn sprintf "FILEHANDLE EXISTS AND HERE IT IS: %s",
    Dumper($fh);
    
#### OUTPUT
Warning:
FILEHANDLE EXISTS AND HERE IT IS $VAR1 = bless( \*Symbol::GEN16, 'Net:
+:FTP::I' );
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And in looking at Net::FTP::I it is fairly apparent that he is making use of the hash reference of this generated symbol:

package Net::FTP::I;

use vars qw(@ISA $buf $VERSION);
use Carp;

require Net::FTP::dataconn;

@ISA = qw(Net::FTP::dataconn);
$VERSION = "1.08"; # $Id: //depot/libnet/Net/FTP/I.pm#6$

sub read {
  my    $data      = shift;
  local *buf      = \$_[0]; shift;
  my    $size    = shift || croak 'read($buf,$size,[$timeout])';
  my    $timeout = @_ ? shift : $data->timeout;

  $data->can_read($timeout) or
     croak "Timeout";

  my($b,$n,$l);
  ## *** the line below implies use of the hash part of 
  ## *** the type glob
  my $blksize = ${*$data}{'net_ftp_blksize'}; #
  $blksize = $size if $size > $blksize;
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But my question is: how could I redo my original call to Dumper() so that it dumped every aspect of the typeglob that $fh referred to?