From mboxrd@z Thu Jan 1 00:00:00 1970 From: Michael Kerrisk Subject: Re: [patch 0/3] add rt_tgsigqueueinfo syscall [RESEND] Date: Sat, 28 Feb 2009 21:46:35 +1300 Message-ID: References: <20090226133339.875832967@linutronix.de> <20090228024424.D237CFC3DA@magilla.sf.frob.com> Reply-To: mtk.manpages-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20090228024424.D237CFC3DA-nL1rrgvulkc2UH6IwYuUx0EOCMrvLtNR@public.gmane.org> Sender: linux-api-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Roland McGrath Cc: Thomas Gleixner , LKML , Oleg Nesterov , Ingo Molnar , Linux API , drepper-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org List-Id: linux-api@vger.kernel.org On 2/28/09, Roland McGrath wrote: >> With respect to the first point, it seems to me reasonably likely that >> there would be use cases where the receiving thread wants to know the >> thread ID of the sender -- especially when sender and receiver are in >> the same process. > > But expecting si_pid to play that role is bizarre. Oh -- I wasn't suggeting that si_pid do that task; I was instead wondering if we needed an additional si_threadid field (or some such). > It's never what any > POSIX-like program would do, both since POSIX says si_pid is a process ID, > and because there are no POSIX-like interfaces at all that use Linux TIDs > to refer to threads. (Nod.) > Wanting this only seems plausible within one process. We are in agreement. > In that case, sender > and recipient know they share memory. The normal thing to do (and what > POSIX applications will do) is to store that info somewhere pointed to by > the sigval. Good point. That would be another of dealing with point I wondered about, and probably better than my idea. Cheers, Michael -- Michael Kerrisk Linux man-pages maintainer; http://www.kernel.org/doc/man-pages/ git://git.kernel.org/pub/scm/docs/man-pages/man-pages.git man-pages online: http://www.kernel.org/doc/man-pages/online_pages.html Found a bug? http://www.kernel.org/doc/man-pages/reporting_bugs.html -- To unsubscribe from this list: send the line "unsubscribe linux-api" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html