import { FileSystemWriteChunkType, FileSystemWritableFileStream } from './types';
export declare class FileSystemWritableFileStreamImpl extends WritableStream implements FileSystemWritableFileStream {
    private _closed;
    constructor(underlyingSink?: UnderlyingSink<FileSystemWriteChunkType>, strategy?: QueuingStrategy<FileSystemWriteChunkType>);
    close(): Promise<void>;
    seek(position: number): Promise<void>;
    truncate(size: number): Promise<void>;
    write(data: FileSystemWriteChunkType): Promise<void>;
}