On Tue, 13 Jul 1999 14:21:49 -0400 (EDT) 
 "Charles M. Hannum" <root@ihack.net> wrote:

 > `Give this man a ceeegar!'
 > 
 > That's precisely the point.  It looks to me like you're trying to
 > create some `generic' interface where it simply isn't appropriate.
 > FS-specific ioctl(2)s could easily handle this operation, without
 > needing to `infect' the VFS interface at all.

...except, in addition to the DMFS file system, a compressing file system
might want this, as might an encrypting file system.  Basically, you'd
add it in more than one place, so why not let a generic file descriptor
attribute do the trick, especially one you can set when you open the
file?

(Note, you want ALT_IO _per file descriptor_, not per file).

        -- Jason R. Thorpe <thorpej@nas.nasa.gov>