anchor.diff:  procedure TAbZipDirectoryFileHeader.SaveToStream( Stream : TStream );
   var
     ExtraFieldLength, FileCommentLength, FileNameLength : Word;
  +  pBytes: TBytes;
   begin
     with Stream do begin
       {write the valid signature from the constant}
  
positive.code: 
      FExtraField.LoadFromStream( Stream, ExtraFieldLength );
  
      SetLength( FFileComment, FileCommentLength );
      if FileCommentLength > 0 then
        Read( FFileComment[1], FileCommentLength );
    end;
    if not IsValid then
      raise EAbZipInvalid.Create;
  
negative.code:     function GetDeflationOption : TAbZipDeflationOption;
      function GetDictionarySize : TAbZipDictionarySize;
      function GetExtraField : TAbExtraField;
      function GetFileComment : string;
      function GetGeneralPurposeBitFlag : Word;
      function GetHostOS: TAbZipHostOS;
      function GetInternalFileAttributes : Word;
  