Path: utzoo!mnetor!uunet!lll-winken!lll-tis!ames!mailrus!tut.cis.ohio-state.edu!osu-cis!att-cb!att-ih!ihnp4!chinet!les
From: les@chinet.UUCP (Leslie Mikesell)
Newsgroups: comp.dcom.lans
Subject: Re: NFS vs RFS
Message-ID: <4633@chinet.UUCP>
Date: 6 Apr 88 20:13:54 GMT
References: <4456@chinet.UUCP> <1016@nusdhub.UUCP>
Reply-To: les@chinet.UUCP (Leslie Mikesell)
Distribution: na
Organization: Chinet - Public Access Unix
Lines: 44

In article <1016@nusdhub.UUCP> rwhite@nusdhub.UUCP (Robert C. White Jr.) writes:
>So, WHAT _IS_ the problem??  This is all in the standard you know, have
>YOU READ the standard??  [excuse me, aledged standard]
No, I assumed that it was proprietary to AT&T - are we talking about the
same RFS?
Let me give an example of what you can do with similar machines (I just
tried this with 3B2s linked via starlan to be sure it works).
Mount / from machine a under /a on machine b  <- pretty arbitrary, actually
                                                as long as /dev is accessible
log into machine b
execute kermit
set line /a/dev/tty23   <- happens to be a nearby terminal on machine a
                           permissions set to rwrwrw for test
set speed 1200          <- terminal was running at 9600
connect
.. go to terminal, switch speed to 1200, type back and forth
   with terminal connected to machine b

Neither kermit nor machine a's tty driver knows anything about the network
or RFS; it works because the ioctl() executed on machine b delivers "struct
termio" to the driver on machine a transparently.

>	2) I write a BIT swizzeler routine.
OK if you happen to know about the device driver in question.
>		3b) I decide any special-case restrictions for item 2.
This will preclude special ioctls to devices you don't know about even
among identical machines.
>
>that 1) Those special calls are deleivered by special means.  2) you will
>ALWAYS know when you are getting these special calls.  3) the contents of
>these special calls are NOT a mystery.  4) if the order of data on one
Umm.. Do you think the network software should know the contents of
struct updata (needed to dial a 3B1 internal modem), struct fmtstruct (for
formatting a 3b2 floppy), dev_dump (for the cartridge tape) ad infinitum...?

>Pardon me for getting a little frustrated, but none of this is unique
>to RFS.  any packeting "standard" [like X.25] talks about forign concepts
As far as I know, no other system even attempts transparent access to remote
devices accessed directly through the file system.
This does not really diminish the usefulness of RFS, since it is an additional
benifit when using similar machines.  However, it does point out the need
for a standard way of representing the contents of a structure whose elements
are not known ahead of time.
   Les Mikesell
                   ...ihnp4!chinet!les