From mboxrd@z Thu Jan  1 00:00:00 1970
Message-ID: <90419a9db8615542cfea064dbbe5cdfc@coraid.com>
From: erik quanstrom <quanstro@coraid.com>
Date: Tue, 13 Mar 2007 10:22:10 -0500
To: 9fans@cse.psu.edu
Subject: Re: [9fans] How can I shift a variable other than ?
In-Reply-To: <f5a0854171ee48f2df8424e98ee5024f@vitanuova.com>
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strictly speaking, <> could be implemented with no help
from rc (and more generally) as in

	boxredir fdin fdout cmd

okay, that's a bit silly, but the point between essential and
non-essential is in the eye of the beholder.

odd digression:

in the late 60s the fad was to rewrite bigger instruction sets in
terms of smaller ones (the metric was # of instructions).  somebody
had a 16 instruction set that someone else reimplemented in 8
instructions.  the apollo guidance computer had 12 instructions and
a few magic memory locations.  it was finally determinted you could get by on
one instruction --- some variation on predecrement and branch
if negative.  "look ma, no instructions."  unfortunately, this machine
was somewhat difficult to program

- erik