From mboxrd@z Thu Jan 1 00:00:00 1970 From: Roland McGrath Subject: Re: [patch 0/3] add rt_tgsigqueueinfo syscall [RESEND] Date: Fri, 27 Feb 2009 18:44:24 -0800 (PST) Message-ID: <20090228024424.D237CFC3DA@magilla.sf.frob.com> References: <20090226133339.875832967@linutronix.de> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: Michael Kerrisk's message of Saturday, 28 February 2009 14:53:23 +1300 Sender: linux-api-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: mtk.manpages-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org Cc: Thomas Gleixner , LKML , Oleg Nesterov , Ingo Molnar , Linux API , drepper-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org List-Id: linux-api@vger.kernel.org > 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. 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. Wanting this only seems plausible within one process. 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. Thanks, Roland -- 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