'Initialize master signal handling. Most of the signals
are queued. Child signals only wake up the master.'

def init_signals(self):

    for p in self.PIPE:
        os.close(p)
    self.PIPE = pair = os.pipe()
    for p in pair:
        util.set_non_blocking(p)
        util.close_on_exec(p)
    self.log.close_on_exec()
    for s in self.SIGNALS:
        signal.signal(s, self.signal)
    signal.signal(signal.SIGCHLD, self.handle_chld)
