THPDFHeadlessFDFDifferencesResult record

The result of one FDF Differences apply, reporting the exact byte accounting of the published revision

THPDFHeadlessFDFDifferencesResult = record
  BaseBytes, PriorAppendBytes, TotalAppendBytes, AddedBytes: Int64;
  NoOp: Boolean;
end;

BaseBytes is the byte length of the explicitly selected complete base revision the caller bound

PriorAppendBytes counts bytes appended by earlier revisions ahead of this apply; TotalAppendBytes counts all append bytes including this one and AddedBytes counts only the bytes this apply appended

NoOp is True exactly when an equivalent Differences payload was already applied, the current PDF bytes are preserved unchanged and AddedBytes is zero

The record layout is stable for the C ABI; the Windows JSON operation fdf.differences.apply reports the same fields in its result JSON

SaveFDFDifferencesToFile · FDF Differences transport