Constrained Network test does not fail fast under fatal conditions.

media/tools/constrained_network_server/cn.py

 #!/usr/bin/env python
 # Copyright (c) 2011 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 """A script for configuring constraint networks.
 
 Sets up a constrained network configuration on a specific port. Traffic on this
 port will be redirected to another local server port.
 
@@ skipping 48 matching lines @@
                      (indent_first, '', opt_width, s, COMMANDS[s].desc))
 
   parser.usage = ('usage: %%prog {%s} [options]\n\n%s' %
                   ('|'.join(COMMANDS.keys()), '\n'.join(cmd_usage)))
 
   parser.add_option('--port', type='int',
                     help='The port to apply traffic control constraints to.')
   parser.add_option('--server-port', type='int',
                     help='Port to forward traffic on --port to.')
   parser.add_option('--bandwidth', type='int',
-                    help='Bandwidth of the network in kbps.')
+                    help='Bandwidth of the network in kbit/s.')
   parser.add_option('--latency', type='int',
                     help=('Latency (delay) added to each outgoing packet in '
                           'ms.'))
   parser.add_option('--loss', type='int',
                     help='Packet-loss percentage on outgoing packets. ')
   parser.add_option('--interface', type='string',
                     help=('Interface to setup constraints on. Use "lo" for a '
                           'local client.'))
   parser.add_option('-v', '--verbose', action='store_true', dest='verbose',
                     default=False, help='Turn on verbose output.')
@@ skipping 34 matching lines @@
   user_cmd, config = _ParseArgs()
 
   try:
     COMMANDS[user_cmd].dispatch(config)
   except traffic_control.TrafficControlError as e:
     logging.error('Error: %s\n\nOutput: %s', e.msg, e.error)
 
 
 if __name__ == '__main__':
   Main()