Re: Win95 partitions

Gordon Chaffee (chaffee@odie.cs.berkeley.edu)
Fri, 25 Oct 1996 06:58:45 -0700 (PDT)


In article <Pine.PTX.3.92.961024004721.29069A-100000@eng3.sequent.com>,
Erik Walthinsen (Omega) <omega@sequent.com> wrote:
>
>One problem I just ran head-first into is that the 'vfat' and 'umsdos'
>filesystem types are completely distinct. Therefore, you can get
>Win95-ish long filenames and no perms, and you can get unix-ish long
>filenames perms, but you can't get both.

>I find this to be slightly strange. What I understand of the current
>hierarchy for DOS filesystems is this: (turned sideways)
>
> /------- MSDOS
> VFS------FAT------<-----UMSDOS
> \-------- VFAT
>
>So the VFAT code is in a distinct module (if you use them), totally
>separate from the UMSDOS and MSDOS code.

This diagram is incorrect. Instead, the current layout is

/----MSDOS<-----UMSDOS
VFS<-----FAT<-----<---------------/
\----VFAT

I'm working on support of uvfat, support for umsdos over a uvfat filesystem.
With uvfat, the diagram looks like

/----MSDOS - - - \
VFS<-----FAT<-----<-----------------UFAT module (supports uvfat and umsdos)
\----VFAT - - - /

The ufat module will support running over either vfat or msdos. It works
for the basic stuff right now, but it needs testing and handling of some
cases that don't work right now. If you create long filenames under
uvfat, it will create vfat long filenames and the long filenames
will be visible under umsdos. If you create long filenames under umsdos,
they will be visible with uvfat, but no long vfat filenames will be created.

---
Gordon Chaffee
chaffee@bugs-bunny.cs.berkeley.edu
http://bmrc.berkeley.edu/people/chaffee