anchor.diff:    j : Integer;
   begin
     { prepare for the checksum calculation }
  -  HdrBuffer := PAnsiChar(@TarH);                                         
  +  HdrBuffer := PAnsiChar(@TarH);
     HdrChkSum := 0;
   
     {calculate the checksum, a simple sum of the bytes in the header}
  
positive.code:     {build Items list from tar header records}
  
      { reset Tar }
  	ItemFound := (FStream.Size > 0) and TarHelp.FindFirstItem;
  	if ItemFound then FArchFormat := UNKNOWN_FORMAT
  	else FArchFormat := V7_FORMAT;
  
      { while more data in Tar }
      while (FStream.Position < FStream.Size) and ItemFound do begin
  
negative.code: {All the first 345 bytes are the same. }
  {   "USTAR_header": Prefix(155): 345-499,
                      empty(12): 500-511 }
  { "old_gnu_header": atime(12): 345-356,
                      ctime(12): 357-368,
                      offset(12): 369-380,
                      longnames(4): 381-384,
  