/**
 * [WHO]: SchedulerLockOptions, tryAcquireSchedulerLock, releaseSchedulerLock
 * [FROM]: Depends on node:fs/promises, node:path
 * [TO]: Consumed by ./cron-scheduler, ./index
 * [HERE]: extensions/builtin/loop/cron/cron-tasks-lock.ts - scheduler lease lock for scheduled_tasks.json
 *
 * Scheduler lease lock for <agentDir>/cron/scheduled_tasks.lock.
 *
 * Modeled on Claude Code's src/utils/cronTasksLock.ts. When multiple Catui
 * sessions share the same agent dir, only one should drive the cron
 * scheduler. The first session to acquire this lock becomes the scheduler;
 * others stay passive and periodically probe the lock. If the owner dies
 * (PID no longer running), a passive session takes over.
 *
 * Pattern mirrors computerUseLock.ts: O_EXCL atomic create, PID liveness
 * probe, stale-lock recovery, cleanup-on-exit.
 */
/**
 * Options for callers that don't have bootstrap state.
 * lockIdentity should be stable for the lifetime of one process.
 */
export type SchedulerLockOptions = {
    dir?: string;
    lockIdentity?: string;
};
/**
 * Try to acquire the scheduler lock for the current session.
 * Returns true on success, false if another live session holds it.
 *
 * Uses O_EXCL ('wx') for atomic test-and-set. If the file exists:
 *   - Already ours → true (idempotent re-acquire)
 *   - Another live PID → false
 *   - Stale (PID dead / corrupt) → unlink and retry exclusive create once
 *
 * If two sessions race to recover a stale lock, only one create succeeds.
 */
export declare function tryAcquireSchedulerLock(opts: SchedulerLockOptions, sessionId: string): Promise<boolean>;
/**
 * Release the scheduler lock if the current session owns it.
 */
export declare function releaseSchedulerLock(opts: SchedulerLockOptions, sessionId: string): Promise<void>;