LAST_FRAG
#define LAST_FRAG ((ulong_t)1 << 31)
#define LAST_FRAG(x) ((ntohl(*(uint32_t *)x) & (1U << 31)) == (1U << 31))
#define LAST_FRAG (((uint32_t)1 << 31))
#define LAST_FRAG 0x80000000