From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Michael Kerrisk (man-pages)" Subject: Re: [PATCH] resolver.3: documents missing options used by _res structure defined in resolv.h and indicates defaults options Date: Mon, 09 Mar 2015 08:24:38 +0100 Message-ID: <54FD4AB6.3090102@gmail.com> References: <20090505194602.GA7897@cavendish.icomputing.pl> <1425761903-22748-1-git-send-email-saulery@free.fr> <54FC0642.6050800@gmail.com> <20150308120348.GB2050@free.fr> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: In-Reply-To: <20150308120348.GB2050-GANU6spQydw@public.gmane.org> Sender: linux-man-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: =?UTF-8?B?U3TDqXBoYW5lIEF1bGVyeQ==?= Cc: mtk.manpages-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org, 527136-forwarded-61a8vm9lEZVf4u+23C9RwQ@public.gmane.org, linux-man-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: linux-man@vger.kernel.org Hello St=C3=A9phane, On 03/08/2015 01:03 PM, St=C3=A9phane Aulery wrote: > Hi Michael, >=20 > I made another patch with all your remarks. Did you send it already. (No hurry--it's just that I wonder if I missed= it.) > Le dimanche 08 mars 2015 =C3=A0 09:20:18, Michael Kerrisk (man-pages)= a =C3=A9crit : >> >>> +.TP >>> +.B RES_USE_INET6 >>> +Try a AAAA query before an A query inside the >> >> s/a AAAA/an AAAA/ >=20 > This is a copy of resolv.conf.5. I will fix this too. Yup. Thanks. >>> +.B RES_BLAST >>> +When resolvers want to even out the load on their nameservers, fol= lowing >>> +them.=20 >> >> I do not understand that last sentence. Could you clarify please. >=20 > I must admit that it's not clear to me either. I think this means tha= t > server alias are swapped between each request. I have wrong? The word > "blast" leaves me skeptical. >=20 > What I found in code source: >=20 >>>From resolv.h: >=20 > #define RES_BLAST 0x00020000 /* blast all recursive server= s */ >=20 > Form res_send.c >=20 > /* > * Some resolvers want to even out the load on their nameservers. > * Note that RES_BLAST overrides RES_ROTATE. > */ > if (__builtin_expect ((statp->options & RES_ROTATE) !=3D 0, 0) && > (statp->options & RES_BLAST) =3D=3D 0) { > struct sockaddr_in6 *ina; > unsigned int map; >=20 > n =3D 0; > while (n < MAXNS && EXT(statp).nsmap[n] =3D=3D MAXNS) > n++; > if (n < MAXNS) { > ina =3D EXT(statp).nsaddrs[n]; > map =3D EXT(statp).nsmap[n]; > for (;;) { > ns =3D n + 1; > while (ns < MAXNS > && EXT(statp).nsmap[ns] =3D=3D MAXNS) > ns++; > if (ns =3D=3D MAXNS) > break; > EXT(statp).nsaddrs[n] =3D EXT(statp).nsaddrs[ns]; > EXT(statp).nsmap[n] =3D EXT(statp).nsmap[ns]; > n =3D ns; > } > EXT(statp).nsaddrs[n] =3D ina; > EXT(statp).nsmap[n] =3D map; > } > } Okay -- I leave it to your discretion to choose what to do here. >>> Note this option overrides >>> +.BR RES_ROTATE . >>> +.TP >>> +.B RES_USEBSTRING >>> +Make reverse IPv6 lookups using the bit-label format described in = RFC 2673; >>> +if this option is not set, then nibble format is used (since glibc= 2.3.4). >> >> Does the "(since glibc 2.3.4)" apply to the option, or to the >> "then nibble format is used"? It's not clear. If the former, then wr= ite >=20 > I don't no. I picked this from resolv.conf.5. > It should be for RES_USEBSTRING. Okay. Cheers, Michael --=20 Michael Kerrisk Linux man-pages maintainer; http://www.kernel.org/doc/man-pages/ Linux/UNIX System Programming Training: http://man7.org/training/ -- To unsubscribe from this list: send the line "unsubscribe linux-man" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html