On 5/4/24 2:30 PM, Paul Eggert wrote:
>> But, I think the next POSIX revision has <endian.h> like Glibc which I
>> prefer.
>
> If the past is any guide, an advantage of the C23 version is that in
> the long run it is likely to be more portable. POSIX is an extension
> of C.
True. But I don't think C23 has the conversion macros:
/* big endian 32 to host. */
uint32_t be32toh (uint32_t);
/* little endian 32 to host. */
uint32_t le32toh (uint32_t);
like the next POSIX revision has and I am a fan of.
I assume the addition of <endian.h> was inspired by glibc's
implementation. glibc seems to have extended <sys/endian.h> from the
BSDs by adding those conversion macros.
Since <sys/endian.h> seems resonably portable, that could do the bulk
of the work for non glibc systems.
GCC even has these:
$ echo | gcc -dM -E - | grep 'ENDIAN'
#define __ORDER_LITTLE_ENDIAN__ 1234
#define __FLOAT_WORD_ORDER__ __ORDER_LITTLE_ENDIAN__
#define __ORDER_PDP_ENDIAN__ 3412
#define __ORDER_BIG_ENDIAN__ 4321
#define __BYTE_ORDER__ __ORDER_LITTLE_ENDIAN__
Collin
