From: clemc@ccc.com (Clem Cole)
Subject: [TUHS] Shell control through external commands
Date: Thu, 14 Jul 2016 09:23:04 -0400 [thread overview]
Message-ID: <CAC20D2Mho6xh+LPucpXmt7QjJge+qc59LYaF+wfhrm3QVOLpWg@mail.gmail.com> (raw)
In-Reply-To: <4fcf31ef-50af-10b5-0c34-ad647ed10a4e@aueb.gr>
Could you be confusing the fact the true and false were implemented by
external commands in some early shell's
On Thu, Jul 14, 2016 at 9:18 AM, Diomidis Spinellis <dds at aueb.gr> wrote:
> I remember hearing that originally the Unix shell had control structures
> (e.g. if, while, case) implemented through external commands. However, I
> can't see this reflected in the source code. The 7th Edition Bourne shell
> has these commands built-in (usr/src/cmd/sh/cmd.c), while the 6th Edition
> (usr/source/s2/sh.c) seems to lack them completely.
>
> The only external command I found was glob, which performed wildcard
> expansion.
>
> Am I missing something? Was this implemented in a version that was never
> released? If so, does anyone know how this implementation worked? (Nested
> commands might require holding some sort of globally accessible stack.)
>
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next prev parent reply other threads:[~2016-07-14 13:23 UTC|newest]
Thread overview: 69+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-07-14 13:18 Diomidis Spinellis
2016-07-14 13:23 ` Clem Cole [this message]
2016-07-14 14:12 ` Mary Ann Horton
2016-07-14 22:36 ` Dave Horsfall
2016-07-14 22:47 ` Corey Lindsly
2016-07-14 22:49 ` Peter Jeremy
2016-07-14 23:27 ` Marc Rochkind
2016-07-15 10:13 ` Joerg Schilling
[not found] ` <CAH_OBieVFzPn93L8=_fmbUycZ7UmYdXiopC0vgei6RGDZp0mHw@mail.gmail.com>
[not found] ` <CAH_OBie_6gFy+BqkCMj+sr0NqTMNOQxvgWf6SQnHMJpn7DAytA@mail.gmail.com>
2016-07-14 23:56 ` shawn wilson
2016-07-15 1:04 ` Dave Horsfall
2016-07-15 1:22 ` Steve Nickolas
2016-07-15 2:25 ` arnold
2016-07-16 6:26 ` Dave Horsfall
2016-07-15 2:25 ` Random832
2016-07-15 3:59 ` Dave Horsfall
2016-07-15 4:09 ` Random832
2016-07-15 13:55 ` Chet Ramey
2016-07-14 23:10 ` Ronald Natalie
2016-07-15 1:41 ` Nemo
2016-07-15 9:00 ` Tony Finch
2016-07-14 14:11 ` schoedel
2016-07-14 14:38 ` Diomidis Spinellis
2016-07-14 15:46 ` John Cowan
2016-07-14 16:30 ` Random832
2016-07-14 22:32 ` Dave Horsfall
2016-07-15 4:29 Rudi Blom
2016-07-15 12:27 Norman Wilson
2016-09-10 7:45 ` Dario Niedermann
2016-09-10 9:13 ` Michael Kjörling
2016-09-10 9:41 ` Joerg Schilling
2016-09-10 17:06 ` Random832
2016-09-10 17:45 ` Dario Niedermann
2016-09-10 19:53 ` Dan Cross
2016-09-10 20:02 ` Chet Ramey
2016-09-10 20:27 ` Dario Niedermann
2016-09-11 10:03 ` Diomidis Spinellis
2016-09-12 10:05 ` Jacob Goense
2016-07-15 16:47 Doug McIlroy
2016-09-10 17:40 ` Dario Niedermann
2016-09-10 19:22 ` arnold
2016-09-12 8:35 ` markus schnalke
2016-09-12 9:25 ` Joerg Schilling
2016-09-12 12:41 ` Tony Finch
2016-09-12 12:50 ` Joerg Schilling
2016-09-13 0:17 ` Sven Mascheck
2016-09-13 1:45 ` Sven Mascheck
2016-09-13 9:20 ` Joerg Schilling
2016-09-12 20:12 ` Dave Horsfall
2016-09-12 21:36 ` Dave Horsfall
2016-09-10 22:43 ` Dave Horsfall
2016-09-11 1:24 ` Ron Natalie
2016-09-11 2:39 ` arnold
2016-09-11 2:41 ` Ronald Natalie
2016-09-11 4:07 ` Dave Horsfall
2016-09-11 5:01 ` arnold
2016-09-12 5:49 ` Dave Horsfall
2016-09-10 14:57 Nemo
2016-09-11 17:39 Doug McIlroy
2016-09-11 18:11 ` Clem Cole
2016-09-11 18:27 ` Dan Cross
2016-09-11 18:50 ` Sven Mascheck
2016-09-11 22:13 ` Random832
2016-09-12 0:27 Doug McIlroy
2016-09-12 1:31 Norman Wilson
2016-09-12 9:33 ` Joerg Schilling
2016-09-12 1:43 Norman Wilson
2016-09-12 9:18 ` Joerg Schilling
2016-09-12 12:56 Norman Wilson
2016-09-12 12:57 Norman Wilson
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