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Date: Mon, 10 Mar 2003 15:33:37 -0800 (PST)
From: Linus Torvalds <torvalds@transmeta.com>
To: Felipe Alfaro Solana <felipe_alfaro@linuxmail.org>
cc: akpm@digeo.com, <george@mvista.com>, <cobra@compuserve.com>,
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Subject: Re: Runaway cron task on 2.5.63/4 bk?
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On Tue, 11 Mar 2003, Felipe Alfaro Solana wrote:
>  
> why not sleep(0)? 

I think a much more likely (and correct) usage for big sleep values is 
more something like this:

	do_with_timeout(xxx, int timeout)
	{
		struct timespec ts;

		... set up some async event ..
		ts.tv_nsec = 0;
		ts.tv_sec = timeout;
		while (nanosleep(&ts, &ts)) {
			if (async event happened)
				return happy;
		}
		.. tear down the async event if it didn't happen ..
	}

and here the natural thing to do in user space is to just make the "no 
timeout" case be a huge value.

At which point it is a _bug_ in the kernel if we return early with some 
random error code.

		Linus

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