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From: louie@sayshell.umd.edu (Louis A. Mamakos)
Newsgroups: comp.os.misc,rec.ham-radio
Subject: Re: What should a scheduler do?
Message-ID: <1990Dec17.214336.8190@ni.umd.edu>
Date: 17 Dec 90 21:43:36 GMT
References: <1990Dec06.212613.25912@ism.isc.com> <PCG.90Dec16234627@teachb.cs.aber.ac.uk>
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In article <PCG.90Dec16234627@teachb.cs.aber.ac.uk> pcg@cs.aber.ac.uk (Piercarlo Grandi) writes:
>What you want to do is essentially a network server like Mach, or user
>implemented domains like 4.2BSD (not yet implemented).  Your network
>server is a (possibly multithreaded) process that takes "messages" from
			^^^^^^^^^^^
>local processes, packs them up, and then accesses the hardware interface
>to send them over a particular medium (or viceversa of course).

Be very careful here.  The KA9Q NOS software assumes that each of the
tasks are run to completion, and are *NOT* timesliced.  When I did the
port of the NOS code to the Amiga, I investigated scrapping much of
the tasking package used in NOS, and using native Amiga processes
(after all, it is a multi tasking operating system on the Amiga).  The
problem is that there are not synchronization primitives to protect
against a NOS task being interrupted before it voluntarily gives up
control.

In the end, I continued to use the NOS tasker, and just ran it all as
one Amiga process.

louie
WA3YMH