signal_getsignal.py

#!/usr/bin/env python

# this is from The Python
# Standard Library by example
# ISBN13: 9780321767349

# this was written for signals in OSX
# when you run this on a linux system it
# asks for an integer and complains about
# line 25.
import signal


def alarm_received(n, stack):
    return

signal.signal(signal.SIGALRM, alarm_received)

signals_to_names = dict(
    (getattr(signal, n), n)
    for n in dir(signal)
    if n.startswith('sig') and '_' not in n
)

for s, name in sorted(signals_to_names.items()):
    handler = signal.getsignal(s)
    if handler is signal.SIG_DFL:
        handler = 'SIG_DFL'
    elif handler is signal.SIG_IGN:
        handler = 'SIG_IGN'
    print '%-10s (%2d):' % (name, s), handler