title: Transfer file using Dropbox API directly to remote FTP server without downloading intermediate file
body: <p>I have large design files (up to 500 MB) on Dropbox, and I'm building a tool to transfer a single file programmatically to a vendor's FTP server in our online PHP-based project management program. Because of the file size, I don't want to download the file to the server, then upload that file to the FTP server, due to both speed and storage space issues.</p>
  
  <p>I can use the following Dropbox API call:</p>
  
  <pre><code>getFile( string $path, resource $outStream, string|null $rev = null )
  Downloads a file from Dropbox. The file's contents are written to the given $outStream and the file's metadata is returned.
  </code></pre>
  
  <p>And I'm guessing I can use the following PHP command:</p>
  
  <pre><code>ftp_fput ( resource $ftp_stream , string $remote_file , resource $handle , int $mode [, int $startpos = 0 ] )
  Uploads the data from a file pointer to a remote file on the FTP server.
  </code></pre>
  
  <p>I don't have any experience with file data streams, so I have no idea how to connect the two. After a couple of hours of online searching, I figured I'd try asking here.</p>
  
  <p>How do I connect getFile's $outstream resource with ftp_fput's $ftp_stream resource?</p>