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From: John Levine via TUHS <tuhs@tuhs.org>
To: tuhs@tuhs.org
Subject: [TUHS] Re: [COFF] SOSP 1973 [was Multics<->Unix Re: Re: History of cal(1)?
Date: 20 Sep 2025 21:12:53 -0400	[thread overview]
Message-ID: <20250921011253.BA763DD04BD2@ary.qy> (raw)
In-Reply-To: <076df8c1-1616-4224-88cc-85923f7d1735@technologists.com>

It appears that Charles H Sauer (he/him) via TUHS <sauer@technologists.com> said:
>> Before UNIX, almost all OS's were written in assembler, ...
>
>Emphasis on "portable," since there seemed to be so many competing 
>processor architectures. Charlie

Yup. Until the late 1960s computers had such widely different addressing and
data architectures that it wouldn't have made sense to try to write portable
system software. FORTRAN and COBOL programs could be fairly portable, but at a
much higher level of abstraction than an operating system.

But S/360 became the de facto standord for mainframes, and a few years later the
PDP-11 was successful enough as a mini that the only data format that mattered
was twos-complement binary, and the only addressing was 8 bit bytes.

That made portability a lot easier.  The only attempt I know to put Unix on a machine
that didn't have 8-bit bytes was the BBN C70 with 10-bit bytes.  One of the programmers
told me that finding all the 8-bit assumptions in Unix applications was very painful.

R's,
John

  reply	other threads:[~2025-09-21  1:13 UTC|newest]

Thread overview: 10+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2025-09-19 21:49 [TUHS] Re: [COFF] SOSP 1973 [was Multics<->Unix Re: Re: History of cal(1)? Noel Chiappa via TUHS
2025-09-19 21:59 ` Charles H Sauer (he/him) via TUHS
2025-09-21  1:12   ` John Levine via TUHS [this message]
2025-09-21  5:25     ` Niklas Karlsson via TUHS
2025-09-22 12:51       ` Lars Brinkhoff via TUHS
2025-09-22 15:19     ` Phillip Harbison via TUHS
2025-09-22 15:24       ` Phillip Harbison via TUHS
2025-09-22 15:41       ` Lars Brinkhoff via TUHS
2025-09-22 16:45         ` Phillip Harbison via TUHS
2025-09-24  0:33         ` Dave Horsfall via TUHS

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