old_contents: import logging
  import os
  import socket
  import sys
  
  from Process import Process
  
  def get_display_number():
  	"""Find a free display number trying to connect to 6000+ ports"""
  	retries = 20
  	display_number = 1
  	display_is_free = False
  	
  	while not display_is_free and retries > 0:
  		s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
  		try:
  			s.connect(('127.0.0.1', 6000 + display_number))
  			logging.info('Display %d is already in use. Trying next.' % (display_number))
  			s.close()
  
  			display_number += 1
  			retries -= 1
  		except:
  			display_is_free = True
  
  	if display_is_free:
  		return display_number
  	else:
  		logging.error('Cannot find a free display.')
  		sys.exit(0)
  
  class XephyrProcess(Process):
  	def __init__(self):
  		self._display = get_display_number()
  		cmd = 'Xephyr :%d -ac -screen 640x480' % (self._display) 
  		Process.__init__(self, cmd)
  		
  	def get_name(self):
  		return 'Xephyr'
  
  	def start(self):
  		Process.start(self)
  		os.environ['DISPLAY'] = ":%d" % (self._display)
  
  class XnestProcess(Process):
  	def __init__(self):
  		self._display = get_display_number()
  		cmd = 'Xnest :%d -geometry 640x480' % (self._display) 
  		Process.__init__(self, cmd)
  		
  	def get_name(self):
  		return 'Xnest'
  
  	def start(self):
  		Process.start(self)
  		os.environ['DISPLAY'] = ":%d" % (self._display)
  
  class Emulator:
  	"""The OLPC emulator"""
  
  	def __init__(self):
  		pass
  	
  	def start(self):
  		try:
  			process = XephyrProcess()
  			process.start()
  		except:
  			try:
  				process = XnestProcess()
  				process.start()
  			except:
  				logging.error('Cannot run the emulator. You need to install Xephyr or Xnest.')				
  				sys.exit(0)
  
new_contents: import logging
  import os
  import socket
  import sys
  
  from Process import Process
  
  def get_display_number():
  	"""Find a free display number trying to connect to 6000+ ports"""
  	retries = 20
  	display_number = 1
  	display_is_free = False
  	
  	while not display_is_free and retries > 0:
  		s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
  		try:
  			s.connect(('127.0.0.1', 6000 + display_number))
  			logging.info('Display %d is already in use. Trying next.' % (display_number))
  			s.close()
  
  			display_number += 1
  			retries -= 1
  		except:
  			display_is_free = True
  
  	if display_is_free:
  		return display_number
  	else:
  		logging.error('Cannot find a free display.')
  		sys.exit(0)
  
  class XephyrProcess(Process):
  	def __init__(self):
  		self._display = get_display_number()
  		cmd = 'Xephyr :%d -ac -screen 640x480' % (self._display) 
  		Process.__init__(self, cmd)
  		
  	def get_name(self):
  		return 'Xephyr'
  
  	def start(self):
  		Process.start(self)
  		os.environ['DISPLAY'] = ":%d" % (self._display)
  
  class XnestProcess(Process):
  	def __init__(self):
  		self._display = get_display_number()
  		cmd = 'Xnest :%d -ac -geometry 640x480' % (self._display) 
  		Process.__init__(self, cmd)
  		
  	def get_name(self):
  		return 'Xnest'
  
  	def start(self):
  		Process.start(self)
  		os.environ['DISPLAY'] = ":%d" % (self._display)
  
  class Emulator:
  	"""The OLPC emulator"""
  
  	def __init__(self):
  		pass
  	
  	def start(self):
  		try:
  			process = XephyrProcess()
  			process.start()
  		except:
  			try:
  				process = XnestProcess()
  				process.start()
  			except:
  				logging.error('Cannot run the emulator. You need to install Xephyr or Xnest.')				
  				sys.exit(0)
  
subject: Add some options to Xnest