export declare const F_OK: number, R_OK: number, W_OK: number, X_OK: number;
export declare function exists(filename: string, mode?: number): Promise<boolean>;
export declare function sanitizePath(filepath: string): Promise<string>;
export declare function whichBin(programName: string): Promise<string>;
export declare function which(program: string, rejectOnMissing?: boolean): Promise<string>;