The code snippet in CGI (in PROCESSING_A_FILE_UPLOAD_FIELD) tells us: 
  $lightweight_fh  = $q->upload('field_name');

  # undef may be returned if it's not a valid file handle
  .
  .
  .

[download]
Hence the problem you're seeing is not entirely unexpected - by Lincoln Stein i.e. the module author, anyway;-)

A user level that continues to overstate my experience :-))

In reply to Re: Getting a filehandle for uploaded file by Bloodnok
in thread Getting a filehandle for uploaded file by luker

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