From mboxrd@z Thu Jan  1 00:00:00 1970
From: dot@dotat.at (Tony Finch)
Date: Mon, 12 Sep 2016 13:41:10 +0100
Subject: [TUHS] Shell control through external commands
In-Reply-To: <57d6748e.CNiWgn0QxOuugldp%schily@schily.net>
References: <201607151647.u6FGlqvW037575@tahoe.cs.Dartmouth.EDU>
 <20160910174011.GF5970@dnied%tiscali.it>
 <201609101922.u8AJMmtq024477@freefriends.org> <1bjMiH-10N-00@marmaro.de>
 <57d6748e.CNiWgn0QxOuugldp%schily@schily.net>
Message-ID: <alpine.DEB.2.11.1609121337110.28546@grey.csi.cam.ac.uk>

Joerg Schilling <schily at schily.net> wrote:
>
> The colon was introduced by AT&T around 1983.

It's a builtin in the v7 Bourne shell - see SYSNULL in msg.c (which
has the command name table) and in xec.c (which has the implementation)

http://www.tuhs.org/Archive/PDP-11/Trees/V7/usr/src/cmd/sh/

Tony.
-- 
f.anthony.n.finch  <dot at dotat.at>  http://dotat.at/  -  I xn--zr8h punycode
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