title: Error code 1 when trying to unzip bin.gz file
body: <p>I was following along <a href="https://stackoverflow.com/questions/7044808/using-r-to-download-gzipped-data-file-extract-and-import-data">this</a> SO post on how to download and unzip a file.</p>
  
  <pre><code>url &lt;- 'https://s3.amazonaws.com/dl4j-distribution/GoogleNews-vectors-negative300.bin.gz'
  file &lt;- basename(url)
  download.file(url, file)
  
  tmpdir &lt;- tempdir()
  untar(file, compressed = 'gzip', exdir = tmpdir)
  </code></pre>
  
  <p>Everything runs fine in the above block except the last line which returns </p>
  
  <pre><code>&gt; untar(file, compressed = 'gzip', exdir = tmpdir)
  tar: Unrecognized archive format
  tar: Error exit delayed from previous errors.
  Warning message:
  In untar(file, compressed = "gzip", exdir = tmpdir) :
    ‘/usr/bin/tar -xf 'GoogleNews-vectors-negative300.bin.gz' -C '/var/folders/ll/g08vjcnd33vdhf250bbg9230fdw13f/T//RtmpAICV5a'’ returned error code 1
  </code></pre>
  
  <p>How can I unzip GoogleNews-vectors-negative300.bin.gz after downloading it?</p>