title: pxssh throwing End Of File (EOF). Exception style platform exception
body: <p>I am having problem using pxssh module. My code is below:</p>
  
  <pre><code>    try:
          ssh_handle = pxssh.pxssh(timeout=None)
          ssh_handle.logfile = sys.stdout
          ssh_handle.login(host, username, password)
          index = ssh_handle.expect(['Are you sure you want to continue connecting \(yes\/no\)\? ', '.*?password:.*', '.*?\$.*'])
          if index == 0:
              ssh_handle.sendline('yes')
              ssh_handle.sendline(password)
          if index == 1:
              ssh_handle.sendline(password)
          ssh_handle.sendline('sudo -s')
          ssh_handle.sendline(password)
          return ssh_handle
      except pxssh.ExceptionPxssh as e:
          print "SSH connection to %s failed" % host
          sys.exit()
  </code></pre>
  
  <p>For some reason I keep getting the error:</p>
  
  <pre><code>File "/usr/lib/python2.7/dist-packages/pexpect/pxssh.py", line 313, in login
      if not self.sync_original_prompt(sync_multiplier):
    File "/usr/lib/python2.7/dist-packages/pexpect/pxssh.py", line 205, in sync_original_prompt
      b = self.try_read_prompt(sync_multiplier)
    File "/usr/lib/python2.7/dist-packages/pexpect/pxssh.py", line 168, in try_read_prompt
      prompt += self.read_nonblocking(size=1, timeout=timeout)
    File "/usr/lib/python2.7/dist-packages/pexpect/__init__.py", line 919, in read_nonblocking
      raise EOF('End Of File (EOF). Exception style platform.')
  pexpect.EOF: End Of File (EOF). Exception style platform.
  </code></pre>
  
  <p>I am not sure what I am doing wrong and would appreciate any pointers anyone might have.</p>
  
  <p>Thanks in advance,
  nav</p>