daemonizer.py 文件源码

def become_daemon(self, root_dir='/'):
        if os.fork() != 0:  # launch child and ...
            os._exit(0)  # kill off parent
        os.setsid()
        os.chdir(root_dir)
        os.umask(0)
        if os.fork() != 0: # fork again so we are not a session leader
            os._exit(0)
        sys.stdin.close()
        sys.__stdin__ = sys.stdin
        sys.stdout.close()
        sys.stdout = sys.__stdout__ = _NullDevice()
        sys.stderr.close()
        sys.stderr = sys.__stderr__ = _NullDevice()
        for fd in range(1024):
            try:
                os.close(fd)
            except OSError:
                pass