Path: utzoo!attcan!uunet!aplcen!samsung!cs.utexas.edu!rice!sun-spots-request
From: watmath!enme3!caveh@uunet.uu.net (Caveh Jalali)
Newsgroups: comp.sys.sun
Subject: Re: Virtual File System
Keywords: Networks
Message-ID: <3219@brazos.Rice.edu>
Date: 16 Nov 89 09:41:04 GMT
Sender: root@rice.edu
Organization: Sun-Spots
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X-Sun-Spots-Digest: Volume 8, Issue 204, message 6 of 18

In article <2751@brazos.Rice.edu> Robert.Smart@ditmela.oz.au (Robert Smart) writes:
>X-Sun-Spots-Digest: Volume 8, Issue 183, message 12 of 13
>
>The SunOS documentation makes brief mention of a Virtual File System
>layer. Is there any available information on how to create your own VFS?

If I understand the question correctly, you want to implement your own
file system.  In this case you don't want your own VFS, you want your own
FS -- this can be implemented "using" NFS.

The simplest example of such a beast is automount.  All automount does is
to mount itself (a NFS daemon, but user process) on /home.  now, all
subsequent accesses to /home are routed to this process using a set of
RPCs (the standard ones defined by NFS).  You now have full control over
such operations as directory lookups, file reads, etc...  everything you
need to implement a file system.  In the case of automount, only symlinks
and directory reads are implemented.  It's a very clever way to avoid
having to do "anything".  I had a good laugh when I figured this one out!

here are some areas which will set you on the right track (sun manuals):
1. RPC & rpcgen
2. NFS protocol def'n (RPC)
3. mount - in particular mounting a process (NFS)