Path: utzoo!utgpu!jarvis.csri.toronto.edu!rutgers!att!alberta!ubc-cs!van-bc!resrch
From: lphillips@lpami.wimsey.bc.ca (Larry Phillips)
Newsgroups: comp.sys.amiga
Subject: Re: Multi-tasking and OS books
Message-ID: <2413@van-bc.UUCP>
Date: 14 May 89 16:43:50 GMT
Sender: resrch@van-bc.UUCP
Lines: 28

In <11336@polyslo.CalPoly.EDU>, dorourke@polyslo.CalPoly.EDU (David M. O'Rourke) writes:
>  Multi-tasking is the ability to have more than one process resident, and
>the ability to schedual more than one process to have access to the CPU.
>All the OS books I've ever seen only require some form of task schedualing,
>the most popular {and probably best} scheme is with an external clock that
>triggers a CPU context switch to a task manager, that then decides who gets
>the next time slice of CPU.  Failing to have an eternal clock, you then have
>to perform the task switch at some other time.  I believe hooking this
>task switch in with one or more OS calls is an undesierable, but workable
>way of doing things.  Your right multi-finder isn't pre-emptive, but it
>is multi-tasking.

You can call it multitasking if you want, but there is little difference
between making the user call for a context switch via keyboard or mouse action,
and making the currently running application call for a context switch via a
system call.

I think I'll call my Amiga a VM machine, because I can fake it in a program.

-larry

--
  - Don't tell me what kind of a day to have! -
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|   //   Larry Phillips                                                |
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