Lib/test/test_signal.py

   1 # Test the signal module
   2 from test_support import verbose, TestSkipped
   3 import signal
   4 import os
   5 import sys
   6
   7 if sys.platform[:3] in ('win', 'os2'):
   8     raise TestSkipped, "Can't test signal on %s" % sys.platform[:3]
   9
  10 if verbose:
  11     x = '-x'
  12 else:
  13     x = '+x'
  14 pid = os.getpid()
  15
  16 # Shell script that will send us asynchronous signals
  17 script = """
  18  (
  19         set %(x)s
  20         sleep 2
  21         kill -5 %(pid)d
  22         sleep 2
  23         kill -2 %(pid)d
  24         sleep 2
  25         kill -3 %(pid)d
  26  ) &
  27 """ % vars()
  28
  29 def handlerA(*args):
  30     if verbose:
  31         print "handlerA", args
  32
  33 HandlerBCalled = "HandlerBCalled"       # Exception
  34
  35 def handlerB(*args):
  36     if verbose:
  37         print "handlerB", args
  38     raise HandlerBCalled, args
  39
  40 signal.alarm(20)                        # Entire test lasts at most 20 sec.
  41 signal.signal(5, handlerA)
  42 signal.signal(2, handlerB)
  43 signal.signal(3, signal.SIG_IGN)
  44 signal.signal(signal.SIGALRM, signal.default_int_handler)
  45
  46 os.system(script)
  47
  48 print "starting pause() loop..."
  49
  50 try:
  51     while 1:
  52         if verbose:
  53             print "call pause()..."
  54         try:
  55             signal.pause()
  56             if verbose:
  57                 print "pause() returned"
  58         except HandlerBCalled:
  59             if verbose:
  60                 print "HandlerBCalled exception caught"
  61             else:
  62                 pass
  63
  64 except KeyboardInterrupt:
  65     if verbose:
  66         print "KeyboardInterrupt (assume the alarm() went off)"