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Date: Wed, 7 Mar 2007 14:01:33 -0800
From: "Ulrich Drepper" <drepper@gmail.com>
To: "Linus Torvalds" <torvalds@linux-foundation.org>
Subject: Re: [patch 1/4] signalfd v1 - signalfd core ...
Cc: "Davide Libenzi" <davidel@xmailserver.org>,
       "Jeremy Fitzhardinge" <jeremy@goop.org>,
       "Stephen Rothwell" <sfr@canb.auug.org.au>,
       "Linux Kernel Mailing List" <linux-kernel@vger.kernel.org>,
       "Andrew Morton" <akpm@linux-foundation.org>
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On 3/7/07, Linus Torvalds <torvalds@linux-foundation.org> wrote:
> > 1) You want standard delivery only:
> >
> >    - Just dont use signalfd
> >
> > 2) you want signalfd only:
> >
> >    - Do a sigprocmask(SIG_BLOCK) of the same mask you pass to signalfd
> >
> > If you want both, you can have it. Race free.
>
> .. but maybe with more code and lots of confusion. I'm still unclear on
> any upsides here.
>
> Choice is good, but only if it's *useful* choice.

Not only that.  If you don't force that the signal is blocked when
using signalfd() you are bound to run into problems.  For the same
reason is it required to have signals blocked when you use sigwait()
etc.  Don't try to innovate here, I guarantee you it's going to break
something somewhere.