lfs_dirheader64
__CTASSERT(sizeof(struct lfs_dirheader64) == 12);
struct lfs_dirheader64 u_64;
__CTASSERT(__alignof(union lfs_dirheader) == __alignof(struct lfs_dirheader64));
struct lfs_dirheader64 dot_header;
struct lfs_dirheader64 dotdot_header;
((fs)->lfs_is64 ? sizeof(struct lfs_dirheader64) : sizeof(struct lfs_dirheader32))
(sizeof(struct lfs_dirheader64) + (((LFS_MAXNAMLEN+1)+1 + 3) & ~3))