import type { DatabaseSync } from 'node:sqlite';
type BackupFileSyncOperations = {
    open(path: string, flags: string): number;
    fsync(fd: number): void;
    close(fd: number): void;
};
/** Windows requires write access on a file handle before FlushFileBuffers/fsync. */
export declare function flushBackupFile(backupPath: string, operations?: BackupFileSyncOperations): void;
/** Offline migrations must reject processes that still hold the database open. */
export declare function assertDatabaseOffline(databasePath: string): void;
/** Create and verify an offline SQLite backup before a cross-version cutover. */
export declare function backupDatabaseBeforeCutover(db: DatabaseSync, databasePath: string, label: string): string;
/** The old release does not participate in an application lock, so check open handles. */
export declare function backupBeforeConversationCutover(db: DatabaseSync, databasePath: string): string;
export {};