def _request(self, process=None, wait=None):
        """helper for building pvRequests

        :param str process: Control remote processing.  May be 'true', 'false', 'passive', or None.
        :param bool wait: Wait for all server processing to complete.
        """
        opts = []
        if process is not None:
            opts.append('process=%s' % process)
        if wait is not None:
            if wait:
                opts.append('wait=true')
            else:
                opts.append('wait=false')
        return 'field()record[%s]' % (','.join(opts))