import socket, sys, struct, time
hostname = 'time.nist.gov'
port = 37
host = socket.gethostbyname(hostname)
s = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
s.sendto('', (host, port))
print "Looking for replies; press Ctrl-C to stop."
buf = s.recvfrom(2048)[0]
if len(buf) != 4:
print "Wrong-sized reply %d: %s" % (len(buf), buf)
sys.exit(1)
secs = struct.unpack("!I", buf)[0]
secs -= 2208988800
print time.ctime(int(secs))