How to determine file being redirected to in C

[Guy Harris]

>Does st_dev become unique for each remote filesystem or does it just
>get a bit set to indicate that it is remote?

The SunOS version makes "st_dev" unique; it doesn't set a bit, it
constructs the "st_dev" on the fly, based on local information.

I don't know about the RFS version; life gets more complicated with RFS,
since, as I remember, if you mount an RFS file system you also end up
mounting all the file systems mounted on directories in that file
system.  If that's true, then you may have some headaches with those
submounted file systems (and may also have RFS-mounted file systems not
providing POSIX-compliant semantics; given that, AT&T will presumably
fix that to work, somehow).  (The same problem may exist with some of
the changes that have been posted to make NFS servers do that - *caveat
emptor*!)