From mboxrd@z Thu Jan 1 00:00:00 1970 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on inbox.vuxu.org X-Spam-Level: X-Spam-Status: No, score=-2.0 required=5.0 tests=MAILING_LIST_MULTI, RCVD_IN_DNSWL_MED,RCVD_IN_MSPIKE_H3,RCVD_IN_MSPIKE_WL, SUBJ_OBFU_PUNCT_FEW,SUBJ_OBFU_PUNCT_MANY autolearn=ham autolearn_force=no version=3.4.4 Received: (qmail 10314 invoked from network); 24 Aug 2020 22:09:39 -0000 Received: from mother.openwall.net (195.42.179.200) by inbox.vuxu.org with ESMTPUTF8; 24 Aug 2020 22:09:39 -0000 Received: (qmail 32723 invoked by uid 550); 24 Aug 2020 22:09:36 -0000 Mailing-List: contact musl-help@lists.openwall.com; run by ezmlm Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-ID: Reply-To: musl@lists.openwall.com Received: (qmail 32705 invoked from network); 24 Aug 2020 22:09:35 -0000 Date: Mon, 24 Aug 2020 18:09:23 -0400 From: Rich Felker To: musl@lists.openwall.com Message-ID: <20200824220922.GN3265@brightrain.aerifal.cx> References: <5232EC15-7E60-4D1F-BF3B-C31BFF998C06@rb67.eu> <20200824161646.GH3265@brightrain.aerifal.cx> <20200824164326.GI3265@brightrain.aerifal.cx> <87mu2jycum.fsf@mid.deneb.enyo.de> <20200824213215.GL3265@brightrain.aerifal.cx> <0422ED16-0AA3-402E-8103-940EC2545A3B@rb67.eu> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <0422ED16-0AA3-402E-8103-940EC2545A3B@rb67.eu> User-Agent: Mutt/1.5.21 (2010-09-15) Subject: Re: [musl] Incompatible behaviour of res_query(3) w.r.t. NXDOMAIN On Mon, Aug 24, 2020 at 11:51:52PM +0200, Daniel Neri wrote: > On 24 Aug 2020, at 23:32, Rich Felker wrote: > > > > Does such a distinction exist? I thought res_query was just equivalent > > to res_mkquery+res_send and that calling res_send directly would get > > you the same errors. > > I thought so too, but I’ve been reading the musl implementation. ;-) > > After looking more at the other implementations, I think Florian is > correct though: it’s more like res_mkquery+res_send+setting h_errno > and the return value based on the RCODE of the response. If this is indeed the case and the right behavior can be obtained reliably by ignoring res_query and using res_mkquery+res_send, I have no fundamental objection to changing this. However we should have a plan for moving h_errno to be thread-local and figuring out what breakage if any there could be for apps built with it global. Thankfully, it looks like we're already using (*__h_errno_location()) even though it was not thread-local, so existing apps built against current musl headers should be immediately compatible with changing it to be thread-local. Rich