Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!samsung!uunet!gsm001!gsm
From: gsm@gsm001.uucp (Geoffrey S. Mendelson)
Newsgroups: comp.sys.mac.system
Subject: Re: True Multitasking, True Object-oriented, True anything.
Message-ID: <1991Jan22.161856.2883@gsm001.uucp>
Date: 22 Jan 91 16:18:56 GMT
References: <6082@stpstn.UUCP> <1991Jan22.035748.275@d.cs.okstate.edu> <1991Jan22.082018.14641@maverick.ksu.ksu.edu>
Organization: Geoffrey S. Mendelson -- Software Consulting
Lines: 33

jxf@orion.cis.ksu.edu (Jerry Frain)  Wrote:
>
>I would agree with this argument, except for one thing.  The term
>"multitasking," I believe, is derived from the feature of Ada to
>allow the programmer to establish separate threads of control.

The first use, I know of, of the words "task" and "multitasking" applied
to the IBM OS/360 circa 1966.


Program execution was  controlled by a Task Control Block (TCB).  
You could either LINK (expecting to return) or 
XCTL (transfer control, no return) to another task and it would run under your 
TCB.  If you ATTACHed a task, a separate TCB was created and viola' you
were multitasking.


By the way, if anyone cares, it was pre-emptive multitasking.  In those
day the operating system designers were concered with sharing an expensive
resource (the computer) among many cheap users (people).  Now
the computers are cheap and the people are expensive.

Mendelson's first law of micro-computers: 

"Micro computer designers consider it their GOD given right to make the
same mistakes mainframe designers did twenty years ago." :-)  

N.b.  I think I should change it to thirty years. :-)
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