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From: Derek Fawcus via COFF <coff@tuhs.org>
To: coff@tuhs.org
Subject: [COFF] Re: Terminology query - 'system process'?
Date: Tue, 19 Dec 2023 13:54:49 +0000	[thread overview]
Message-ID: <ZYGgqbskKUcZ4GLC@clarinet.employees.org> (raw)
In-Reply-To: <20231214232935.802BB18C08F@mercury.lcs.mit.edu>

On Thu, Dec 14, 2023 at 06:29:35PM -0500, Noel Chiappa wrote:
> Interestingly, other early systems don't seem to have thought of this structuring technique.

How early does that have to be?  MP/M-1.0 (1979 spec) mentions this,
as "Resident System Processes"

    http://www.bitsavers.org/pdf/digitalResearch/mpm_I/MPM_1.0_Specification_Aug79.pdf

It was a banked switching, multiuser, multitasking system for a Z80/8080.
It mentions 5 such processes.

Later versions, and the 8086 version still had them. The MP/M-86 docs mention
'Terminal Message', Clock, Echo and 'System Status' processes.  I believe the
first was spawned one per console.

(Some of the internal structures suggest it was intended to support swapping,
 but I don't know if that was implemented in terms of disk swapping)

DF


  parent reply	other threads:[~2023-12-19 13:55 UTC|newest]

Thread overview: 22+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2023-12-14 23:29 Noel Chiappa
2023-12-14 23:54 ` Larry McVoy
2023-12-15  1:15 ` Bakul Shah
2023-12-15 17:51   ` Paul Winalski
2023-12-15 18:08     ` Warner Losh
2023-12-16  2:04     ` Greg 'groggy' Lehey
2023-12-16 19:21       ` Paul Winalski
2023-12-16 19:44         ` Paul Winalski
2023-12-15 13:43 ` Dan Cross
2023-12-19 13:54 ` Derek Fawcus via COFF [this message]
  -- strict thread matches above, loose matches on Subject: below --
2023-12-20 20:35 Noel Chiappa
2023-12-20 19:31 Noel Chiappa
2023-12-20 20:29 ` Paul Winalski
2023-12-31  3:51 ` steve jenkin
2023-12-14 21:48 [COFF] " Noel Chiappa
2023-12-14 22:06 ` [COFF] " Bakul Shah
2023-12-14 22:12   ` Warner Losh
2023-12-14 22:09 ` Clem Cole
2023-12-15 14:20   ` Dan Cross
2023-12-15 16:25     ` Warner Losh
2023-12-15 17:13     ` Bakul Shah
2023-12-15  6:24 ` Lars Brinkhoff
2023-12-15 18:30   ` Stuff Received

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