TFileRec is the internal format for typed and untyped files in the Delphi language.

TFileRec = packed record
  Handle: Integer;
  Mode: Word;
  Flags: Word;
  case Byte of
    0: (RecSize: Cardinal;);
    1: (BufSize: Cardinal;
        BufPos: Cardinal;
        BufEnd: Cardinal;
        BufPtr: PChar;
        OpenFunc: Pointer;
        InOutFunc: Pointer;
        FlushFunc: Pointer;
        CloseFunc: Pointer;
        UserData: array[1..32] of Byte;
        Name: array[0..259] of Char;);
end;

struct TFileRec {
  int Handle;
  Word Mode;
  Word Flags;
  unsigned RecSize;
  unsigned BufSize;
  unsigned BufPos;
  unsigned BufEnd;
  const char * BufPtr;
  void * OpenFunc;
  void * InOutFunc;
  void * FlushFunc;
  void * CloseFunc;
  array[1..32] of Byte UserData;
  array[0..259] of Char Name;
};