From owner-freebsd-threads@FreeBSD.ORG Fri Mar 31 21:00:48 2006 Return-Path: X-Original-To: freebsd-threads@freebsd.org Delivered-To: freebsd-threads@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 2574916A422 for ; Fri, 31 Mar 2006 21:00:48 +0000 (UTC) (envelope-from deischen@freebsd.org) Received: from mail.ntplx.net (mail.ntplx.net [204.213.176.10]) by mx1.FreeBSD.org (Postfix) with ESMTP id B167943D6D for ; Fri, 31 Mar 2006 21:00:47 +0000 (GMT) (envelope-from deischen@freebsd.org) Received: from sea.ntplx.net (sea.ntplx.net [204.213.176.11]) by mail.ntplx.net (8.13.6/8.13.6/NETPLEX) with ESMTP id k2VL0kXH002532; Fri, 31 Mar 2006 16:00:46 -0500 (EST) Date: Fri, 31 Mar 2006 16:00:46 -0500 (EST) From: Daniel Eischen X-X-Sender: eischen@sea.ntplx.net To: Niall Douglas In-Reply-To: <442DA512.7000.1E3815@s_sourceforge.nedprod.com> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII X-Virus-Scanned: by AMaViS and Clam AntiVirus (mail.ntplx.net) Cc: freebsd-threads@freebsd.org Subject: Re: recvfrom() not a thread cancellation point X-BeenThere: freebsd-threads@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list Reply-To: Daniel Eischen List-Id: Threading on FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 31 Mar 2006 21:00:48 -0000 On Fri, 31 Mar 2006, Niall Douglas wrote: > On 31 Mar 2006 at 15:40, Daniel Eischen wrote: > > > > How do I receive UDP packets using recvfrom() when it would seem that > > > recvfrom() is not a thread cancellation point on FreeBSD 6.0? > > > > 1) select() or poll() instead, then recvfrom(). UDP packets > > are never partial IIRC. > > Ah, that's a good idea. > > > 2) Unmask a signal in the thread doing the recvfrom(), then > > use pthread_kill() to interrupt it (don't use SA_RESTART > > for sa_flags in the signal action). > > Not practical unfortunately as who knows how many threads are > concurrently doing recvfrom()'s. If you know how to cancel a particular thread, then you know how to send a signal to a particular thread (pthread_kill(tid, sig)). > Thanks for the hint. I hadn't thought of using poll. -- DE