title: Perl: processing files from the command line with -e. How is the passed file accessed?
body: <p>When I invoke Perl like </p>
  
  <pre><code>perl -e '' foo.txt
  </code></pre>
  
  <p>How is foo accessed? </p>
  
  <p>If I use -i, I can edit foo.txt in place. I suppose foo.txt is associated with some file handle and opened for direct access? What would be the handle? If I use -0777, is the file streamed from STDIN (say) and stored in a scalar string or is it opened and read into such a string? Which string?</p>
  
  <p>I understand this may be trivial but I can't seem to find answers.</p>
  
  <p>Thank you very much for any help.</p>