rem: return EINVAL;
add: return FS_EINVAL;
context: do_query(int argc, char **argv){	char buffer[2048];	struct dirent *dent = (struct dirent *)buffer;	void *cookie;	char *query;	int max_err = 10;	int err;	if (argc != 2) {		printf("query string expected");		return EINVAL;	}	query = argv[1];	err = sys_open_query(true, -1, "/myfs/.", query, 0, 42, 42, &cookie);	if (err < 0) {		printf("could not open query: %s\n", strerror(err));		return EINVAL;	}		while (true) {		err = sys_read_query(true, -1, "/myfs/.", cookie, dent, sizeof(buffer), 1);		if (err < 0) {			printf("readdir failed for: %s\n", dent->d_name);			if (max_err-- <= 0)				break;			continue;		}	    		if (err == 0)			break;		printf("%s\n", dent->d_name);	}	err = sys_close_query(true, -1, "/myfs/.", cookie);	if (err < 0) {		printf("could not close query: %s\n", strerror(err));		return err;	}	return 0;}