From owner-freebsd-current@FreeBSD.ORG Fri Feb 20 16:48:32 2004 Return-Path: Delivered-To: freebsd-current@freebsd.org Received: from green.homeunix.org (freefall.freebsd.org [216.136.204.21]) by hub.freebsd.org (Postfix) with ESMTP id 3BF6616A4CE; Fri, 20 Feb 2004 16:48:32 -0800 (PST) Received: from green.homeunix.org (green@localhost [127.0.0.1]) by green.homeunix.org (8.12.10/8.12.9) with ESMTP id i1L0mVHS014393; Fri, 20 Feb 2004 19:48:31 -0500 (EST) (envelope-from green@green.homeunix.org) Received: from localhost (green@localhost)i1L0mVGW014390; Fri, 20 Feb 2004 19:48:31 -0500 (EST) Message-Id: <200402210048.i1L0mVGW014390@green.homeunix.org> X-Mailer: exmh version 2.6.3 04/04/2003 with nmh-1.0.4 To: Daniel Eischen In-Reply-To: Message from Daniel Eischen From: "Brian F. Feldman" Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Date: Fri, 20 Feb 2004 19:48:31 -0500 Sender: green@green.homeunix.org cc: current@FreeBSD.org Subject: Re: Testers wanted: reentrant resolver X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sat, 21 Feb 2004 00:48:32 -0000 Daniel Eischen wrote: > On Fri, 20 Feb 2004, Brian F. Feldman wrote: > > > Daniel Eischen wrote: > > > Ugh, can you put h_errno inside the per-thread res stuff. > > > We shouldn't need to have to add special hooks in the > > > threads libraries for this. > > > > Please explain what you're saying further. On correctly-threaded operating > > systems, h_errno is just like errno -- and I made it act EXACTLY as errno > > acts, and is per-thread storage for everything but the first thread. It's > > absolutely necessary if we want to return the correct errors; even if > > everything else in the world is totally reentrant, if h_errno isn't, the > > wrong errors can be returned! What "special hooks" do you mean? There's no > > way to not change probably hundreds of lines of code without actually doing > > the work to make h_errno thread-safe. It's the only proper thing to do. > > The implementation of __h_errno() need not depend on something > special stuffed in struct pthread. Use thread-local storage > (pthread_getspecific()) like you did for the res_send_private > stuff. Especially since these interfaces should be deprecated > in favor of what looks to be BIND 8.2.2 interfaces (according > to the Solaris man pages). Other APIs have the option of failing. __h_errno() does not have the option of failing, so what do I do if pthread_key_create() fails? Also, if malloc() fails each time pthread_getspecific() returns NULL for the thread? -- Brian Fundakowski Feldman \'[ FreeBSD ]''''''''''\ <> green@FreeBSD.org \ The Power to Serve! \ Opinions expressed are my own. \,,,,,,,,,,,,,,,,,,,,,,\