Time-stamps the whole document and writes the time-stamped file to stream, asynchronously.
public Task TimestampAsync(Stream stream, PdfTimestampClient timestampClient, string? fieldName = null, CancellationToken cancellationToken = default(CancellationToken))
Where to write, from its current position. It is not disposed.
The client of the time-stamp authority.
The signature field to hold the timestamp, or null for a new one.
Cancels the request and the writes.
ISO 32000-2 §12.8.5; RFC 3161. Writes what Timestamp(Stream, PdfTimestampClient, String?) writes; the request and the writes to
stream are asynchronous. A cancelled or failed request leaves the document as it was.