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Date: Wed, 26 May 2010 07:30:45 -0700
From: Andrew Morton <akpm@linux-foundation.org>
To: Jiri Slaby <jirislaby@gmail.com>
Cc: adobriyan@gmail.com, nhorman@tuxdriver.com, oleg@redhat.com,
       linux-kernel@vger.kernel.org
Subject: Re: [PATCH v3 10/11] rlimits: implement prlimit64 syscall
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On Wed, 26 May 2010 14:58:05 +0200 Jiri Slaby <jirislaby@gmail.com> wrote:

> > This could all be done in userspace, couldn't it?  Write a little library
> > which clones a thread then waits for someone to send it a
> > change-your-rlimits message.  Write a little tool to send those
> > messages and voila.
> 
> Sorry, I'm not sure I understand this. Could you shed some light on what
> will run in the new thread?
> 
> A code such as:
> main()
> {
>   if (!clone())
>     exec("something");
> 
>   while (wait_for_message(&m)) {
>      setrlimit(m);
>      sleep();
>   }
> }
> won't obviously work. Could you change it so it reflects your idea or
> explain what I'm missing?

main()
{
	if (clone(...)) {
		while (wait_for_message(&m))
			setrlimit(m);
	}

	...
}
		
?