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Subject: Re: Add pselect, ppoll system calls.
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Linus Torvalds <torvalds@osdl.org>
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Date: Mon, 13 Jun 2005 17:23:21 +1000
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> One pretty simple alternative is to just make the timeout be a global, and 
> have the signal handler clear it, guaranteeing that if we're just about to 
> hit the select(), we'll exit immediately.

That is still racy ... if the signal hits between loading that global to
to pass it to select and the actual syscall entry ... pretty narrow but
still there.