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From:	arnold@cc.gatech.edu (Arnold Robbins)
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Date:	Tue, 18 May 1993 13:08:40 -0400
In-Reply-To: Alan Watson's 52-line message on May 18,  1:01pm
X-Ultrix: Just Say NO!
X-Important-Saying: Premature Optimization Is The Root Of All Evil.
X-Mailer: Mail User's Shell (7.2.3 5/22/91)
To:	rc@hawkwind.utcs.toronto.edu
Subject: Re: A delicious thought

Everything old is new again.....

I read in an early history of unix paper that on the very early unix
systems (pdp-7 vintage!) everything in fact worked this way. You typed
a command. The shell exec'ed it, and then the code in exit() would re-exec
the shell.

When they added fork to the system, they noticed that 'cd' didn't take them
anywhere.... At that point it became built-in to the shell.

I could almost see doing this with limit. cd is a bit expensive, methinks
(just think about the TWO call through nami. One to find cd, the next to
do the chdir. ugh)

Arnold