Subject: Re: Volunteers to test some kernel code...
To: der Mouse <mouse@Rodents.Montreal.QC.CA>
From: Bill Studenmund <>
List: tech-kern
Date: 06/16/1999 12:16:17
On Wed, 16 Jun 1999, der Mouse wrote:

> > Since all the info in a filehandle is needed, I think it'd be much
> > better if they were used instead of dev/ino/gen# tuples.
> What about filesystems that don't support filehandles?  You just can't
> run executables from them?

What file systems don't support file handles?

More to the point, on what file systems which don't support file handles
can you reasonably talk about dev/inode pairs?

Doing a survey, adosfs, filecorefs, cd9660fs, coda, ffs, lfs, ext2fs, and
msdosfs all support fhtovp operations.

Only ntfs and nfs don't support fhtovp. Our nfs doesn't support getting
files by inode #, so fhtovp won't work. I'm not sure if that's an nfs
requirement or a quirk of our implimentation. Note: the dev/ino/gen# vs.
filehandle arguement makes no difference here. They both won't work with
our nfs. :-(

ntfs should be taught about file handles. :-)

I think the survey indicates why filehandles should figure into the
equation - not all of the fs's above mess with generation #'s. By using
filehandles (and the implicit fs-specific length definition), the right
thing happens.

Take care,