BYTE, WORD and DWORD macros definition

Question

I am trying to understand, what would be the best way to define BYTE, WORD and DWORD macros, which are mentioned in answers of this question.

#define LOWORD(l) ((WORD)(l))
#define HIWORD(l) ((WORD)(((DWORD)(l) >> 16) & 0xFFFF))
#define LOBYTE(w) ((BYTE)(w))
#define HIBYTE(w) ((BYTE)(((WORD)(w) >> 8) & 0xFF))

Would it be correct to assume, that:

• BYTE is macro defined as #define BYTE __uint8_t
• WORD is macro defined as #define WORD __uint16_t
• DWORD is macro defined as #define DWORD __uint32_t

If yes, why cast to another macro instead of casting to __uint8_t, __uint16_t or __uint32_t? Is it written like that to increase clarity?

I also found another question which answers include typedef, with little bit more of research I've found answers to question about comparing #define and typedef. Would typedef be better to use in this case?

Answer 1

This is a portable solution:

#include <stdint.h>

typedef uint32_t DWORD;   // DWORD = unsigned 32 bit value
typedef uint16_t WORD;    // WORD = unsigned 16 bit value
typedef uint8_t BYTE;     // BYTE = unsigned 8 bit value

Answer 2

You have it defined at: https://msdn.microsoft.com/en-us/library/windows/desktop/aa383751(v=vs.85).aspx, and that is already defined in Windows Data Type headers for WinAPI:

typedef unsigned short WORD;
typedef unsigned char BYTE;
typedef unsigned long DWORD;

and it is a type, and not a macro.