/**
 * Create an AbortController that is automatically aborted if one of the given
 * signals is aborted.
 *
 * For convenience, the linked AbortSignals can be undefined.
 *
 * If the controller or any of the signals is aborted, all event listeners are
 * removed.
 *
 * @private Internal code, does not follow semantic versioning.
 */
export declare function createLinkedAbortController(...signals: (AbortSignal | undefined)[]): AbortController;
/**
 * Create a deadline signal. The returned object contains an AbortSignal, but
 * also a cleanup function to stop the timer, which must be called once the
 * calling code is no longer interested in the signal.
 *
 * Ideally, we would simply use AbortSignal.timeout(), but it is not widely
 * available yet.
 *
 * @private Internal code, does not follow semantic versioning.
 */
export declare function createDeadlineSignal(timeoutMs: number | undefined): {
    signal: AbortSignal;
    cleanup: () => void;
};
/**
 * Returns the reason why an AbortSignal was aborted. Returns undefined if the
 * signal has not been aborted.
 *
 * The property AbortSignal.reason is not widely available. This function
 * returns an AbortError if the signal is aborted, but reason is undefined.
 *
 * @private Internal code, does not follow semantic versioning.
 */
export declare function getAbortSignalReason(signal: AbortSignal): unknown;