Lib/test/test_signal.py

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