to obtain an initial estimate of the array length needed to store all
the directory entries. Although BSD has historically guaranteed that
st_size is the size of the directory file, POSIX does not, and more to
the point, some recent filesystems such as ZFS use st_size to mean
something else.
The fix is to not stat the directory at all, set the initial
array size to 32 entries, and realloc it in powers of 2 if that
proves insufficient.
PR: 113668