/**
 * @file Linux Secret Service backend via `secret-tool`. `secret-tool` is the
 *   user-facing CLI for libsecret, which talks to any running Secret Service
 *   provider (gnome-keyring, kwallet5, KeePassXC's Secret Service integration,
 *   etc.). Most desktop Linux installs have one; headless / containerized hosts
 *   do not. Storage shape: each item has a `service=<svc> user=<account>`
 *   attribute pair plus the password body. Reads + writes use those two
 *   attributes as the lookup key. The label (`--label`) is what shows up in the
 *   user's keyring UI; we set it to the same string passed in by the caller. No
 *   backing-file fallback. If `secret-tool` isn't on PATH or no Secret Service
 *   provider is running, reads return `undefined` and writes throw with an
 *   actionable hint — callers fall back to env variables for that session.
 */
export declare function deleteLinux(service: string, account: string): Promise<'removed' | 'absent'>;
export declare function deleteLinuxSync(service: string, account: string): 'removed' | 'absent';
export declare function isLinuxBackendAvailable(): boolean;
export declare function readLinux(service: string, account: string): Promise<string | undefined>;
export declare function readLinuxSync(service: string, account: string): string | undefined;
export declare function writeLinux(service: string, account: string, value: string, label: string): Promise<void>;
export declare function writeLinuxSync(service: string, account: string, value: string, label: string): void;
