/**
 * Classifying ssh failures
 *
 * The only place that parses OpenSSH's message text. The job is to tell a
 * transport failure (safe to retry) apart from an authentication failure
 * (retrying is harmful: every attempt counts against the server as a failed
 * login) and from an honest non-zero exit code from the remote command
 * (not a failure at all).
 */
import { SSHRunnerError } from './errors.js';
/** Return code by which ssh reports its own failure */
export declare const SSH_FAILURE_EXIT_CODE = 255;
/**
 * Observed outcome of running ssh
 */
export interface SpawnOutcome {
    /** Process spawn error (ssh not found, etc.) */
    spawnError?: NodeJS.ErrnoException;
    exitCode: number | null;
    stderr: string;
    /** Needed to tell a broken channel apart from a command that itself returned 255 */
    stdout?: string;
}
/** Strip multiplexing housekeeping lines from the command output */
export declare function stripMuxNotices(stderr: string): string;
/**
 * Parse the outcome of a run.
 *
 * @returns A transport error, or null if there was no transport failure and
 *          the result should be treated as a plain ExecResult.
 */
export declare function classifySpawnOutcome(outcome: SpawnOutcome, context: {
    host: string;
    port: number;
    idempotent?: boolean;
}): SSHRunnerError | null;