import os
import signal
import time

ITIMER = 0.1   # seconds
SIGNAMES = ('SIGINT', 'SIGALRM', 'SIGWINCH', 'SIGTERM', 'SIGCHLD')

got_signals = 0

def signal_handler(*args):
    global got_signals
    got_signals += 1

for signame in SIGNAMES:
    if not hasattr(signal, signame):
        continue
    signum = getattr(signal, signame)
    print("Register %s" % signame)
    signal.signal(signum, signal_handler)
    signal.siginterrupt(signum, True)

fd = os.open('.', os.O_RDONLY | os.O_DIRECTORY)

input("ready: disconnect the network cable and press enter to continue")

if hasattr(signal, 'SIGALRM') and ITIMER:
    print("Send SIGALRM every %.1f ms" % (ITIMER * 1e3))
    signal.setitimer(signal.ITIMER_REAL, 1.0, ITIMER)

print("wait a few signals")
while got_signals < 5:
    time.sleep(0.1)

print("fstat...")
t0 = time.monotonic()
st = os.fstat(fd)
dt = time.monotonic() - t0
print("fstat... %.1f ms" % (dt*1e3))

print(st)
os.close(fd)

print("Got %s signals" % got_signals)