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From: jack@boring.UUCP (Jack Jansen)
Newsgroups: net.unix-wizards,net.database
Subject: Re: A variant of the streams idea
Message-ID: <6717@boring.UUCP>
Date: Wed, 1-Jan-86 18:43:28 EST
Article-I.D.: boring.6717
Posted: Wed Jan  1 18:43:28 1986
Date-Received: Thu, 2-Jan-86 05:04:59 EST
References: <2416@ukma.UUCP> <372@ncr-sd.UUCP> <964@brl-tgr.ARPA> <376@ncr-sd.UUCP> <3883@ut-sally.UUCP>
Reply-To: jack@mcvax.UUCP (Jack Jansen)
Organization: AMOEBA project, CWI, Amsterdam
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Doug Gwyn states that files are completely different
from pipes/FIFOs/etc, in that a diskfile doesn't have
a data flow, like the others.

I agree on this, but there's a way to make a file look like
a stream: just say that your not talking to a *file*, but
to a *file server*. This way, you get your stream model
back. Now it's easy to insert modules that do ASCII-EBCDIC
conversion, sparse file handling, database lookups, even
readahead/writebehind, without modifying the basic low-level
file server.
There are great advantages to the file-server model:
- You don't pay for features you didn't ask for (ever heard
database people raving about unix readahead?)
- It's easier to maintain, since it consists of more, but smaller
modules.
- Remote filesystems come for (almost) free.

This is, by the way, the approach used in the Amoeba distributed
operating system, and in some other message-passing operating
systems. Hmm. Time to move to net.os?
-- 
	Jack Jansen, jack@mcvax.UUCP
	The shell is my oyster.