/**
 * v0.7 — concurrent-uninstall guard.
 * Per docs/plan/v0.7-uninstall-lifecycle.md §5.1 precheck + P1 #6.
 *
 * A lockfile at `<workspace>/.solosquad/uninstall.lock` prevents two
 * `solosquad uninstall` invocations from racing each other on the same
 * workspace. The file records the holder's PID and start timestamp, so
 * stale locks (PID dead) are detected and cleared automatically.
 *
 * Atomic acquisition uses `O_CREAT | O_EXCL` (Node `wx` flag), which is
 * race-safe across POSIX and Win32.
 */
export interface LockInfo {
    pid: number;
    startTs: string;
    hostname: string;
}
export interface LockHandle {
    /** Absolute path of the lockfile on disk. */
    path: string;
    /** Release the lock (delete the file). Idempotent. */
    release(): void;
}
export declare class LockHeldError extends Error {
    readonly info: LockInfo;
    readonly lockPath: string;
    constructor(info: LockInfo, lockPath: string);
}
/**
 * Cross-platform "is this PID alive?" probe. Uses `process.kill(pid, 0)` —
 * signal 0 sends no signal but throws ESRCH if the process is gone.
 *
 * On Win32, Node implements signal 0 by calling OpenProcess; permission
 * issues throw EPERM, which we treat as "alive but not ours" (still alive).
 */
export declare function isProcessAlive(pid: number): boolean;
export declare function readLock(lockPath: string): LockInfo | null;
/**
 * Returns true if the lockfile exists but its holder process is gone.
 * Falsy if the lockfile is absent, or holder is alive, or content is
 * unparseable (in which case treat as held to avoid false-clean).
 */
export declare function isStaleLock(lockPath: string): boolean;
export interface AcquireOptions {
    /** Override pid (tests). */
    pid?: number;
    /** Override hostname (tests). */
    hostname?: string;
    /** Override start ts (tests). */
    startTs?: string;
    /**
     * If true and the existing lockfile is stale (holder dead), silently
     * delete it and proceed. Default true — non-stale locks still throw.
     */
    clearStale?: boolean;
}
/**
 * Acquire the lock or throw `LockHeldError` if a live holder exists. The
 * caller is responsible for invoking `release()` in finally blocks.
 */
export declare function acquireLock(lockPath: string, options?: AcquireOptions): LockHandle;
/**
 * Convenience: get the conventional lock path under a workspace.
 */
export declare function uninstallLockPath(workspace: string): string;