* Convert all field values from host order to big-endian so they aren't
byte-swapped when created on little-endian systems.
* Pack the struct so the compiler doesn't insert padding on 64-bit
systems.
* Fix the volume and file creation timestamps by converting them from
UNIX to Macintosh time base, using a function copied from hfsutils.
* Pad volume and file names with null bytes instead of random memory.
* Add the "end of variable-length data" marker so the OS doesn't crash
when trying to resolve the alias.
* Set the alias flag so the OS treats the file as an alias.