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From: sef@kithrup.COM (Sean Eric Fagan)
Newsgroups: comp.arch
Subject: Re: new word order?
Message-ID: <1991Mar02.081830.2049@kithrup.COM>
Date: 2 Mar 91 08:18:30 GMT
References: <606@mtndew.Tustin.CA.US> <1991Mar1.095745.13399@siesoft.co.uk> <1255@TALOS.UUCP>
Organization: Kithrup Enterprises, Ltd.
Lines: 32

In article <1255@TALOS.UUCP> jerry@TALOS.UUCP (Jerry Gitomer) writes:
>imw@siesoft.co.uk (Ian Wild) writes:
>|Didn't Microsoft provide a switch for this in their Xenix cc?
>|Bytes in a long:
>|68xxx:               1 2 3 4
>|80x86 (normally):    4 3 2 1
>|80x86 (+ cc -Mb):    2 1 4 3
>|My question is WHY?
>	Maybe it just can't count in a normal manner.

Disclaimer:  this was all before my time, so I could easily have gotten some
of the details incorrect.

Anyway:  there once was a machine, 8086 based, which ran a Burroughs
Operating System.  CTOS, I think it was called.  It was multitasking and
multiprocessing.  Either SCO or uSoft ported XENIX XT to run under this OS
(actually, *with* it, but it could still be said to run *under* it).  The
machine, either in the hardware or in a software convention, defined that 4
bytes longs were to be of the order

	2 1 4 3

Thus, the switch, and the support for it.  It has a magic number and
everything (Microsoft x.out executable byte-swapped long or some such).

Hopefully, I haven't gotten anything *too* wrong...

-- 
Sean Eric Fagan  | "I made the universe, but please don't blame me for it;
sef@kithrup.COM  |  I had a bellyache at the time."
-----------------+           -- The Turtle (Stephen King, _It_)
Any opinions expressed are my own, and generally unpopular with others.