Atheros vendor-specific messages contain information in mixed endian format. The Ethernet header portion is sent big endian but the Atheros header and payload are sent in little endian . The traditional endian converstion functions htons(), htonl(), ntohs() and ntohl() can be used to perform platform independent conversions on the Ethernet header but not the Atheros header payload.

The Open Powerline Toolkit includes similar macros HTOLE16, HTOLE32, LE16TOH and LE32TOH in endian.h which serve the same function but conform to recommendations for standarized byte order function on Linux, OpenBSD and FreeBSD. Observe that the names are independent of any network implications.

#if BYTE_ORDER == BIG_ENDIAN
#	define LE16TOH(x) __bswap_16(x)
#	define LE32TOH(x) __bswap_32(x)
#	define LE64TOH(x) __bswap_64(x)
#	define HTOLE16(x) __bswap_16(x)
#	define HTOLE32(x) __bswap_32(x)
#	define HTOLE64(x) __bswap_64(x)
#elif BYTE_ORDER == LITTLE_ENDIAN
#	define LE16TOH(x) (x)
#	define LE32TOH(x) (x)
#	define LE64TOH(x) (x)
#	define HTOLE16(x) (x)
#	define HTOLE32(x) (x)
#	define HTOLE64(x) (x)
#else
#error "Undefined host byte order."
#endif

In addition, the Open Powerline Toolkit includes function endian that reverses byte order over a variable-length memory region.