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From: tjt@kobold.UUCP
Newsgroups: net.arch
Subject: Re: Why not virtual files?
Message-ID: <300@kobold.UUCP>
Date: Thu, 26-Apr-84 09:55:36 EST
Article-I.D.: kobold.300
Posted: Thu Apr 26 09:55:36 1984
Date-Received: Sat, 28-Apr-84 09:28:06 EST
References: <333@oliveb.UUCP>
Organization: Masscomp, Westford, MA
Lines: 14

Virtual files (the ability to have data in a file appear as part of
your address space) are used extensively in Multics, and are available
on several other operating systems to varying extents.  The
"demand-loaded" text programs of 4BSD are an example of this, as is the
ill-fated vread system call from 4.1BSD.  The original 4.2BSD
specification included more facilities for mapping files into an
address space, although this has been deferred to 4.3BSD.

By the way, "virtual files" isn't all beer and skittles.  Ever try
mapping your tty into memory?

-- 
	Tom Teixeira,  Massachusetts Computer Corporation.  Westford MA
	...!{ihnp4,harpo,decvax}!masscomp!tjt   (617) 692-6200 x275