No idea if the POSIX subsystem used NTFS or some other filesystem but if it was NTFS it probably just used the same reparse data buffer. It's just that Windows only added a symlink buffer structure in Vista/2008. You can manually use the same data buffer in older Windows versions it just won't know what to do with them just like all the other reparse data structures.
chasil|5 months ago
https://en.wikipedia.org/wiki/Microsoft_POSIX_subsystem
jborean93|5 months ago