Path: utzoo!censor!geac!torsqnt!jarvis.csri.toronto.edu!cs.utexas.edu!usc!ucsd!ucbvax!van-bc!
From: lphillips@lpami.wimsey.bc.ca (Larry Phillips)
Newsgroups: comp.sys.amiga.tech
Subject: Re: resource tracking
Message-ID: <1165@lpami.wimsey.bc.ca>
Date: 24 Feb 90 21:52:26 GMT
Lines: 41
Return-Path: <lpami!lphillips>
To: van-bc!rnews

In <5201@sugar.hackercorp.com>, peter@sugar.hackercorp.com (Peter da Silva) writes:
>> Consider.  A system call does not HAVE to be I/O.  Yes, all I/O to
>> Exec devices and AmigaDOS filesystems involves message passing.  Not
>> all _system_ calls do.  Does AddTask() use messages?  No.  Don't try
>> telling me it's not a system call.
>
>Argh...
>
>OK, let's put it this way. Come up with a program that does soemthing useful
>and doesn't do any IPC at all. About the only thing I can think off is one
>that runs ONLY under the CLI, has no diagnostic messages, and toggles the 7kHz
>filter on and off (or does some other trivial hardware hackery (or hijackery)).

Rather depends on what you mean by a system call and IPC doesn't it? The
programmer need not concern himself that IPC is happening as the result of a
system call, nor does he need to handle messages just because the system is
using them behind his back.

>IPC is integral to the Amiga. Sharing memory between a bunch of tasks is not
>something you can get away from. It's rare on UNIX.

That I'll go along with.

>Maybe I need a disclaimer: "If this message uses different magic incantations
>than the ones you're used to, try to see if that effects the content before
>flaming"?

Perhaps so.. a system call is a system call. That it generates a message or a
series of messages is beside the point. Perhaps you'd enlighten us with your
definition of 'system call'.

-larry

--
Gallium Arsenide is the technology of the future;
  always has been, always will be.
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|   //   Larry Phillips                                                 |
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