Absolute Junction Points/Symlinks

[Zebediah Figura]

Fundamentally I guess we're trying to simultaneously satisfy the 
constraints of

(1) make NT symlinks, regardless of type, behave like Unix symlinks, to 
any host filesystem utilities

(2) make absolute symlinks still work when the prefix is moved, without 
any additional work

Which, barring some brilliant idea, I think just isn't possible, not 
without rewriting how said host utilities work, either by preloading our 
own bits of glibc, or maybe introducing some mount-point-like API to the 
kernel.

Personally, I think dropping constraint (2) is preferable to any hack 
involving preloading. Manually fixing up symlinks after a prefix move 
feels equivalent to manually prepending a wrapper before any filesystem 
operation, but it would have to be done far less often.

I also think it makes more sense to drop constraint (2) than constraint 
(1). I suspect moving a prefix is very rare in practice (though to be 
sure I have done it myself a couple times), whereas accessing the Win32 
filesystem from outside is probably quite common. Additionally, it ends 
up being far less work to rely on host symlink resolution than to have 
to implement it ourselves.