old_contents: #-----------------------------------------------------------------------------
  # Imports
  #-----------------------------------------------------------------------------
  
  import subprocess
  import sys
  
  from IPython.zmq.ipkernel import IPKernelApp
  
  #-----------------------------------------------------------------------------
  # Functions and classes
  #-----------------------------------------------------------------------------
  def pylab_kernel(gui):
      """Launch and return an IPython kernel with pylab support for the desired gui
      """
      kernel = IPKernelApp()
      kernel.initialize(['python', '--pylab=%s' % gui,
                         #'--log-level=10'
                         ])
      return kernel
  
  
  def qtconsole_cmd(kernel):
      """Compute the command to connect a qt console to an already running kernel
      """
      ports = ['--%s=%d' % (name, port) for name, port in kernel.ports.items()]
      return ['ipython', 'qtconsole', '--existing'] + ports
  
  
  class InternalIPKernel(object):
  
      def init_ipkernel(self, backend):
          # Start IPython kernel with GUI event loop and pylab support
          self.ipkernel = pylab_kernel(backend)
          # To create and track active qt consoles
          self._qtconsole_cmd = qtconsole_cmd(self.ipkernel)
          self.consoles = []
          
          # This application will also act on the shell user namespace
          self.namespace = self.ipkernel.shell.user_ns
          # Keys present at startup so we don't print the entire pylab/numpy
          # namespace when the user clicks the 'namespace' button
          self._init_keys = set(self.namespace.keys())
  
          # Example: a variable that will be seen by the user in the shell, and
          # that the GUI modifies (the 'Counter++' button increments it):
          self.namespace['app_counter'] = 0
          #self.namespace['ipkernel'] = self.ipkernel  # dbg
  
      def print_namespace(self, evt=None):
          print "\n***Variables in User namespace***"
          for k, v in self.namespace.iteritems():
              if k not in self._init_keys and not k.startswith('_'):
                  print '%s -> %r' % (k, v)
          sys.stdout.flush()
  
      def new_qt_console(self, evt=None):
          self.consoles.append(subprocess.Popen(self._qtconsole_cmd))
  
      def count(self, evt=None):
          self.namespace['app_counter'] += 1
  
      def cleanup_consoles(self, evt=None):
          for c in self.consoles:
              c.kill()
  
new_contents: #-----------------------------------------------------------------------------
  # Imports
  #-----------------------------------------------------------------------------
  
  import subprocess
  import sys
  
  from IPython.lib.kernel import connect_qtconsole
  from IPython.zmq.ipkernel import IPKernelApp
  
  #-----------------------------------------------------------------------------
  # Functions and classes
  #-----------------------------------------------------------------------------
  def pylab_kernel(gui):
      """Launch and return an IPython kernel with pylab support for the desired gui
      """
      kernel = IPKernelApp.instance()
      kernel.initialize(['python', '--pylab=%s' % gui,
                         #'--log-level=10'
                         ])
      return kernel
  
  
  class InternalIPKernel(object):
  
      def init_ipkernel(self, backend):
          # Start IPython kernel with GUI event loop and pylab support
          self.ipkernel = pylab_kernel(backend)
          # To create and track active qt consoles
          self.consoles = []
          
          # This application will also act on the shell user namespace
          self.namespace = self.ipkernel.shell.user_ns
          # Keys present at startup so we don't print the entire pylab/numpy
          # namespace when the user clicks the 'namespace' button
          self._init_keys = set(self.namespace.keys())
  
          # Example: a variable that will be seen by the user in the shell, and
          # that the GUI modifies (the 'Counter++' button increments it):
          self.namespace['app_counter'] = 0
          #self.namespace['ipkernel'] = self.ipkernel  # dbg
  
      def print_namespace(self, evt=None):
          print "\n***Variables in User namespace***"
          for k, v in self.namespace.iteritems():
              if k not in self._init_keys and not k.startswith('_'):
                  print '%s -> %r' % (k, v)
          sys.stdout.flush()
  
      def new_qt_console(self, evt=None):
          """start a new qtconsole connected to our kernel"""
          return connect_qtconsole(self.ipkernel.connection_file, profile=self.ipkernel.profile)
  
      def count(self, evt=None):
          self.namespace['app_counter'] += 1
  
      def cleanup_consoles(self, evt=None):
          for c in self.consoles:
              c.kill()
  
subject: update internal_ipkernel example to use connection files