Source Code for Module coro.signal_handler

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20   
21  # $Header: //prod/main/ap/shrapnel/coro/signal_handler.py#8 $ 
22   
23  """Signal handler.""" 
24   
25  __version__ = '$Revision: #8 $' 
26   
27  import coro 
28  import signal 
29  import os 
30   
31  UNAME = os.uname()[0] 
32   
33 -def register (signum, handler, once_only=False): 
34      """Register a signal handler. 
35   
36      :Parameters: 
37          - `signum`: The signal number to register. 
38          - `handler`: A callable object that takes one parameter which is the 
39            signal number that was triggered. 
40          - `once_only`: If True, will only trigger once, and then disable the 
41            signal handler.  Defaults to False. 
42   
43      :Exceptions: 
44          - `coro.SimultaneousError`: Another handler is already registered for 
45            this signal. 
46      """ 
47   
48      if UNAME in ('FreeBSD', 'Darwin'): 
49          # first, turn *off* normal signal handling... 
50          signal.signal (signum, signal.SIG_IGN) 
51          # register with kqueue 
52          flags = coro.EV.ADD 
53          if once_only: 
54              flags |= coro.EV.ONESHOT 
55          k_handler = lambda x: handler(x.ident) 
56          coro.set_handler ((signum, coro.EVFILT.SIGNAL), k_handler, flags) 
57      else: 
58          signal.signal(signum, handler) 
59   
60   
61  # alias for backward compatibility 
62  register_signal_handler = register 
63