__init__.py 文件源码

def _wait_service(self):
        """Return the last died service or None"""
        try:
            # Don't block if no child processes have exited
            pid, status = os.waitpid(0, os.WNOHANG)
            if not pid:
                return None
        except OSError as exc:
            if exc.errno not in (errno.EINTR, errno.ECHILD):
                raise
            return None

        if os.WIFSIGNALED(status):
            sig = SIGNAL_TO_NAME.get(os.WTERMSIG(status))
            LOG.info('Child %(pid)d killed by signal %(sig)s',
                     dict(pid=pid, sig=sig))
        else:
            code = os.WEXITSTATUS(status)
            LOG.info('Child %(pid)d exited with status %(code)d',
                     dict(pid=pid, code=code))

        for conf in self._running_services:
            if pid in self._running_services[conf]:
                return conf, self._running_services[conf].pop(pid)

        LOG.error('pid %d not in service list', pid)