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From: Simon Wright <simon.j.wright@mac.com>
Newsgroups: comp.lang.ada
Subject: Re: Tasking issues
Date: Sun, 12 Aug 2007 12:06:52 +0100
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Date: 2007-08-12T12:06:52+01:00
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"Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de> writes:

> I don't understand, tasks are subject of scheduling and time
> sharing. They are switched even if they have something to do.

If you are using an OS with preemptive tasking (eg VxWorks) ready
tasks are only switched when preempted by something of higher
priority. A task can voluntarily move itself to the back of the ready
queue for its priority by "delay 0.0;" (posssibly not RM-mandated
behaviour).

Other OSs with this behaviour included (last time I had to find out)
Solaris for tasks in the RT class and Linux running the program as
root. Don't know about Windows.