filter->rc = send_output_eos(filter->f->next);
filter->rc = send_output_eos(filter->f);
MP_INLINE apr_status_t modperl_output_filter_flush(modperl_filter_t *filter){    int add_flush_bucket = FALSE;        if (((modperl_filter_ctx_t *)filter->f->ctx)->sent_eos) {        /* no data should be sent after EOS has been sent */        return filter->rc;    }    if (filter->flush) {        add_flush_bucket = TRUE;        filter->flush = 0;    }    filter->rc = modperl_wbucket_flush(&filter->wbucket, add_flush_bucket);    if (filter->rc != APR_SUCCESS) {        return filter->rc;    }    if (filter->eos) {        filter->rc = send_output_eos(filter->f->next);        if (filter->bb_in) {            apr_brigade_destroy(filter->bb_in);            filter->bb_in = NULL;        }        filter->eos = 0;    }    return filter->rc;}