Message-ID: <407FDD0A.1050904@nortelnetworks.com>
Date: Fri, 16 Apr 2004 09:18:02 -0400
From: Chris Friesen <cfriesen@nortelnetworks.com>
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To: abhinav singh <abhinav_is_in@yahoo.com>
CC: linux-kernel@vger.kernel.org
Subject: Re: How-to write soft real-time programs Kernel-2.6.x
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abhinav singh wrote:

> So how-to write a simple program(may be a Hello world
> program) which has real-time capabilities.


Something like the following will put you into one of the "realtime" 
scheduling classes, and you will take priority over the normally 
scheduled tasks.


struct sched_param p;
p.sched_priority=50;
if (sched_setscheduler(getpid(), SCHED_RR, &p) < 0) {
	perror("error while setting scheduler class");
	printf("continuing anyways, but results may not be as good\n");
}


The whole issue of soft-realtime is a complicated one, and there are 
many other things that should be done to maximise predictability.


Chris
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