title: PycURL RESUME_FROM
body: <p>I can't seem to get the RESUME_FROM option to work. Here's some example code that I have been testing with:</p>
  
  <pre><code>import os
  import pycurl
  import sys
  
  def progress(total, existing, upload_t, upload_d):
      try:
          frac = float(existing)/float(total)
      except:
          frac = 0
      sys.stdout.write("\r%s %3i%%" % ("file", frac*100)  )
  
  url = "http://launchpad.net/keryx/stable/0.92/+download/keryx_0.92.4.tar.gz"
  filename = url.split("/")[-1].strip()
  
  def test(debug_type, debug_msg):
      print "debug(%d): %s" % (debug_type, debug_msg)
  
  c = pycurl.Curl()
  c.setopt(pycurl.URL, url)
  c.setopt(pycurl.FOLLOWLOCATION, 1)
  c.setopt(pycurl.MAXREDIRS, 5)
  
  # Setup writing
  if os.path.exists(filename):
      f = open(filename, "ab")
      c.setopt(pycurl.RESUME_FROM, os.path.getsize(filename))
  else:
      f = open(filename, "wb")
  c.setopt(pycurl.WRITEDATA, f)
  
  #c.setopt(pycurl.VERBOSE, 1)
  c.setopt(pycurl.DEBUGFUNCTION, test)
  c.setopt(pycurl.NOPROGRESS, 0)
  c.setopt(pycurl.PROGRESSFUNCTION, progress)
  c.perform()
  </code></pre>