#!/usr/bin/env python # # Copyright 2007 Doug Hellmann. # # # All Rights Reserved # # Permission to use, copy, modify, and distribute this software and # its documentation for any purpose and without fee is hereby # granted, provided that the above copyright notice appear in all # copies and that both that copyright notice and this permission # notice appear in supporting documentation, and that the name of Doug # Hellmann not be used in advertising or publicity pertaining to # distribution of the software without specific, written prior # permission. # # DOUG HELLMANN DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE, # INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN # NO EVENT SHALL DOUG HELLMANN BE LIABLE FOR ANY SPECIAL, INDIRECT OR # CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS # OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, # NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN # CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. # """Fork, then send the child process a signal. """ __module_id__ = "$Id$" #end_pymotw_header import os import signal import time def signal_usr1(signum, frame): "Callback invoked when a signal is received" pid = os.getpid() print 'Received USR1 in process %s' % pid print 'Forking...' child_pid = os.fork() if child_pid: print 'PARENT: Pausing before sending signal...' time.sleep(1) print 'PARENT: Signaling %s' % child_pid os.kill(child_pid, signal.SIGUSR1) else: print 'CHILD: Setting up signal handler' signal.signal(signal.SIGUSR1, signal_usr1) print 'CHILD: Pausing to wait for signal' time.sleep(5)