2004-11-03 13:51:07 +00:00
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.\" Copyright (c) 1986 The Regents of the University of California.
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.\" All rights reserved.
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.\"
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2013-03-10 09:29:43 +00:00
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.\" %%%LICENSE_START(PERMISSIVE_MISC)
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2004-11-03 13:51:07 +00:00
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.\" Redistribution and use in source and binary forms are permitted
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.\" provided that the above copyright notice and this paragraph are
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.\" duplicated in all such forms and that any documentation,
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.\" advertising materials, and other materials related to such
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.\" distribution and use acknowledge that the software was developed
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.\" by the University of California, Berkeley. The name of the
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.\" University may not be used to endorse or promote products derived
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.\" from this software without specific prior written permission.
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.\" THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
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.\" IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
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.\" WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
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epoll_create.2, epoll_ctl.2, epoll_wait.2, eventfd.2, fallocate.2, futex.2, getcpu.2, getitimer.2, ioctl_list.2, ioprio_set.2, migrate_pages.2, move_pages.2, pciconfig_read.2, sendfile.2, setns.2, signalfd.2, spu_create.2, spu_run.2, sysinfo.2, timerfd_create.2, backtrace.3, cmsg.3, error.3, getpt.3, getrpcent.3, getrpcport.3, getsubopt.3, offsetof.3, program_invocation_name.3, rpc.3, rpmatch.3, rtnetlink.3, xdr.3, cciss.4, hpsa.4, pts.4, charmap.5, dir_colors.5, elf.5, gai.conf.5, locale.5, nscd.conf.5, nss.5, resolv.conf.5, rpc.5, arp.7, cpuset.7, ddp.7, epoll.7, fifo.7, futex.7, icmp.7, ip.7, ipv6.7, mailaddr.7, netdevice.7, packet.7, raw.7, regex.7, rtnetlink.7, socket.7, spufs.7, tcp.7, udp.7, unix.7, x25.7, ldconfig.8, nscd.8: Global fix: s/END_LICENSE/LICENSE_END/
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
2013-03-12 09:26:07 +00:00
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.\" %%%LICENSE_END
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2004-11-03 13:51:07 +00:00
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.\"
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.\" @(#)resolver.5 5.9 (Berkeley) 12/14/89
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.\" $Id: resolver.5,v 8.6 1999/05/21 00:01:02 vixie Exp $
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.\"
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.\" Added ndots remark by Bernhard R. Link - debian bug #182886
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.\"
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localedef.1, adjtimex.2, clock_nanosleep.2, epoll_ctl.2, ioctl.2, madvise.2, open.2, posix_fadvise.2, prctl.2, restart_syscall.2, sched_setaffinity.2, select.2, semop.2, setsid.2, sgetmask.2, sigaction.2, sigreturn.2, splice.2, syscall.2, syscalls.2, tee.2, tkill.2, abort.3, cmsg.3, exp10.3, ftw.3, getopt.3, ilogb.3, memcmp.3, mq_open.3, pow.3, pthread_setschedparam.3, sigvec.3, sysconf.3, termios.3, tgamma.3, wordexp.3, locale.5, proc.5, resolv.conf.5, cp1251.7, credentials.7, fanotify.7, inotify.7, locale.7, man-pages.7, signal.7, unix.7, ld.so.8: tstamp
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
2014-12-31 06:01:38 +00:00
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.TH RESOLV.CONF 5 2014-12-31 "" "Linux Programmer's Manual"
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2004-11-03 13:51:07 +00:00
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.UC 4
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.SH NAME
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resolv.conf \- resolver configuration file
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.SH SYNOPSIS
|
2007-12-23 08:20:39 +00:00
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.B /etc/resolv.conf
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2004-11-03 13:51:07 +00:00
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.SH DESCRIPTION
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The
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.I resolver
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is a set of routines in the C library
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that provide access to the Internet Domain Name System (DNS).
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The resolver configuration file contains information that is read
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by the resolver routines the first time they are invoked by a process.
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The file is designed to be human readable and contains a list of
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keywords with values that provide various types of resolver information.
|
2014-02-18 23:09:57 +00:00
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The configuration file is considered a trusted source of DNS information
|
2014-02-22 08:56:23 +00:00
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(e.g., DNSSEC AD-bit information will be returned unmodified from this
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source).
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2004-11-03 13:51:07 +00:00
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.LP
|
2012-05-03 19:35:40 +00:00
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If this file does not exist,
|
2012-05-10 18:27:47 +00:00
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only the name server on the local machine will be queried;
|
2008-06-27 03:37:56 +00:00
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the domain name is determined from the hostname
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2004-11-03 13:51:07 +00:00
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and the domain search path is constructed from the domain name.
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.LP
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The different configuration options are:
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.TP
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\fBnameserver\fP Name server IP address
|
2012-11-11 11:08:29 +00:00
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Internet address of a name server that the resolver should query,
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either an IPv4 address (in dot notation),
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or an IPv6 address in colon (and possibly dot) notation as per RFC 2373.
|
2007-12-16 14:23:16 +00:00
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Up to
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.B MAXNS
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(currently 3, see \fI<resolv.h>\fP) name servers may be listed,
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2004-11-03 13:51:07 +00:00
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one per keyword.
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If there are multiple servers,
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the resolver library queries them in the order listed.
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If no \fBnameserver\fP entries are present,
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the default is to use the name server on the local machine.
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(The algorithm used is to try a name server, and if the query times out,
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try the next, until out of name servers,
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then repeat trying all the name servers
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until a maximum number of retries are made.)
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.TP
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\fBdomain\fP Local domain name.
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|
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Most queries for names within this domain can use short names
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|
relative to the local domain.
|
2013-05-19 14:38:43 +00:00
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|
|
If set to \(aq.\(aq, the root domain is considered.
|
2004-11-03 13:51:07 +00:00
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|
|
If no \fBdomain\fP entry is present, the domain is determined
|
2008-06-27 03:37:56 +00:00
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|
|
from the local hostname returned by
|
2008-04-18 15:45:03 +00:00
|
|
|
.BR gethostname (2);
|
2008-06-09 15:49:35 +00:00
|
|
|
the domain part is taken to be everything after the first \(aq.\(aq.
|
2008-06-27 03:37:56 +00:00
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|
|
Finally, if the hostname does not contain a domain part, the root
|
2004-11-03 13:51:07 +00:00
|
|
|
domain is assumed.
|
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|
|
.TP
|
|
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|
|
\fBsearch\fP Search list for host-name lookup.
|
|
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|
|
The search list is normally determined from the local domain name;
|
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|
|
by default, it contains only the local domain name.
|
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|
|
This may be changed by listing the desired domain search path
|
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|
|
following the \fIsearch\fP keyword with spaces or tabs separating
|
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|
the names.
|
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|
|
Resolver queries having fewer than
|
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|
|
.I ndots
|
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|
|
dots (default is 1) in them will be attempted using each component
|
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|
of the search path in turn until a match is found.
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|
For environments with multiple subdomains please read
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|
|
.BI "options ndots:" n
|
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|
|
below to avoid man-in-the-middle attacks and unnecessary
|
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|
traffic for the root-dns-servers.
|
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|
.\" When having a resolv.conv with a line
|
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.\" search subdomain.domain.tld domain.tld
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|
.\" and doing a hostlookup, for example by
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|
|
.\" ping host.anothersubdomain
|
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|
|
.\" it sends dns-requests for
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.\" host.anothersubdomain.
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|
.\" host.anothersubdomain.subdomain.domain.tld.
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.\" host.anothersubdomain.domain.tld.
|
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|
.\" thus not only causing unnecessary traffic for the root-dns-servers
|
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|
.\" but broadcasting information to the outside and making man-in-the-middle
|
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|
.\" attacks possible.
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Note that this process may be slow and will generate a lot of network
|
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|
|
traffic if the servers for the listed domains are not local,
|
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|
|
and that queries will time out if no server is available
|
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|
for one of the domains.
|
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|
|
.IP
|
|
|
|
|
The search list is currently limited to six domains
|
|
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|
|
with a total of 256 characters.
|
|
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|
|
.TP
|
|
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|
|
\fBsortlist\fP
|
2009-02-28 21:30:23 +00:00
|
|
|
This option allows addresses returned by
|
2007-06-02 06:22:00 +00:00
|
|
|
.BR gethostbyname (3)
|
|
|
|
|
to be sorted.
|
2009-02-28 21:37:09 +00:00
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|
|
A sortlist is specified by IP-address-netmask pairs.
|
2007-04-12 22:42:49 +00:00
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|
|
The netmask is
|
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|
|
optional and defaults to the natural netmask of the net.
|
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The IP address
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|
|
and optional network pairs are separated by slashes.
|
|
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|
|
Up to 10 pairs may
|
|
|
|
|
be specified.
|
2009-02-28 21:38:03 +00:00
|
|
|
Here is an example:
|
|
|
|
|
|
2007-12-19 06:57:44 +00:00
|
|
|
.in +4n
|
2004-11-03 13:51:07 +00:00
|
|
|
sortlist 130.155.160.0/255.255.240.0 130.155.0.0
|
2007-12-19 06:57:44 +00:00
|
|
|
.in
|
2004-11-03 13:51:07 +00:00
|
|
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.br
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.TP
|
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\fBoptions\fP
|
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|
Options allows certain internal resolver variables to be modified.
|
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|
|
The syntax is
|
|
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|
|
.RS
|
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|
.IP
|
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|
|
\fBoptions\fP \fIoption\fP \fI...\fP
|
|
|
|
|
.LP
|
|
|
|
|
where \fIoption\fP is one of the following:
|
|
|
|
|
.TP
|
|
|
|
|
\fBdebug\fP
|
2009-02-28 19:37:19 +00:00
|
|
|
.\" Since glibc 2.2?
|
2007-12-16 14:23:16 +00:00
|
|
|
sets
|
|
|
|
|
.BR RES_DEBUG
|
|
|
|
|
in
|
2013-03-05 07:06:31 +00:00
|
|
|
.IR _res.options
|
intro.1, _syscall.2, access.2, arch_prctl.2, cacheflush.2, chown.2, clock_getres.2, clone.2, create_module.2, fcntl.2, flock.2, get_kernel_syms.2, get_robust_list.2, get_thread_area.2, getcpu.2, getpriority.2, getrlimit.2, getrusage.2, ioprio_set.2, kexec_load.2, madvise.2, mbind.2, migrate_pages.2, mknod.2, mmap.2, mount.2, move_pages.2, mprotect.2, open.2, pause.2, pciconfig_read.2, perf_event_open.2, prctl.2, ptrace.2, query_module.2, read.2, reboot.2, recv.2, s390_runtime_instr.2, sched_setscheduler.2, select_tut.2, send.2, set_mempolicy.2, setfsgid.2, setfsuid.2, sigaction.2, spu_create.2, spu_run.2, stime.2, swapon.2, syslog.2, timer_create.2, timer_getoverrun.2, times.2, tkill.2, umount.2, unimplemented.2, ustat.2, vm86.2, wait.2, abs.3, aio_read.3, aio_write.3, bsd_signal.3, catgets.3, clearenv.3, cmsg.3, dbopen.3, dirfd.3, dlopen.3, exec.3, fenv.3, ferror.3, fmemopen.3, fnmatch.3, fopen.3, futimes.3, getaddrinfo.3, getifaddrs.3, getipnodebyname.3, hsearch.3, if_nameindex.3, inet_pton.3, mblen.3, mbrlen.3, mbsrtowcs.3, mbtowc.3, mcheck.3, memfrob.3, mq_notify.3, netlink.3, posix_memalign.3, printf.3, pthread_attr_setscope.3, pthread_cleanup_push.3, pthread_kill_other_threads_np.3, pthread_self.3, pthread_setcancelstate.3, pthread_setconcurrency.3, raise.3, resolver.3, rpc.3, rtime.3, rtnetlink.3, scanf.3, setbuf.3, setnetgrent.3, shm_open.3, sigpause.3, sigset.3, sigwait.3, sockatmark.3, strcasecmp.3, strcmp.3, strdup.3, strftime.3, strptime.3, strsignal.3, strverscmp.3, sysv_signal.3, termios.3, wcrtomb.3, wcsnlen.3, wcsnrtombs.3, wcsrtombs.3, wctomb.3, wprintf.3, console_codes.4, cpuid.4, msr.4, rtc.4, sk98lin.4, st.4, tty.4, charmap.5, core.5, elf.5, hosts.equiv.5, proc.5, resolv.conf.5, services.5, slabinfo.5, arp.7, bootparam.7, capabilities.7, charsets.7, cpuset.7, ddp.7, epoll.7, feature_test_macros.7, futex.7, hier.7, icmp.7, inotify.7, ip.7, ipv6.7, man-pages.7, mdoc.7, mdoc.samples.7, netdevice.7, netlink.7, numa.7, packet.7, path_resolution.7, posixoptions.7, pthreads.7, raw.7, rtld-audit.7, rtnetlink.7, sem_overview.7, sigevent.7, socket.7, spufs.7, tcp.7, udp.7, unicode.7, uri.7, utf-8.7, intro.8, ldconfig.8, sync.8: Global fix: fix placement of word "only"
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
2013-03-31 08:53:00 +00:00
|
|
|
(effective only if glibc was built with debug support; see
|
2013-03-05 07:06:31 +00:00
|
|
|
.BR resolver (3)).
|
2004-11-03 13:51:07 +00:00
|
|
|
.TP
|
|
|
|
|
.BI ndots: n
|
2009-02-28 19:37:19 +00:00
|
|
|
.\" Since glibc 2.2
|
2004-11-03 13:51:07 +00:00
|
|
|
sets a threshold for the number of dots which
|
2007-05-12 09:06:04 +00:00
|
|
|
must appear in a name given to
|
2007-05-21 22:14:09 +00:00
|
|
|
.BR res_query (3)
|
2007-05-12 09:06:04 +00:00
|
|
|
(see
|
2004-11-03 13:51:07 +00:00
|
|
|
.BR resolver (3))
|
2007-04-12 22:42:49 +00:00
|
|
|
before an \fIinitial absolute query\fP will be made.
|
|
|
|
|
The default for
|
2007-12-16 14:08:46 +00:00
|
|
|
\fIn\fP is 1, meaning that if there are any dots in a name, the name
|
2004-11-03 13:51:07 +00:00
|
|
|
will be tried first as an absolute name before any \fIsearch list\fP
|
|
|
|
|
elements are appended to it.
|
2009-09-27 07:26:38 +00:00
|
|
|
The value for this option is silently capped to 15.
|
2004-11-03 13:51:07 +00:00
|
|
|
.TP
|
|
|
|
|
.BI timeout: n
|
2009-02-28 19:37:19 +00:00
|
|
|
.\" Since glibc 2.2
|
2004-11-03 13:51:07 +00:00
|
|
|
sets the amount of time the resolver will wait for a
|
|
|
|
|
response from a remote name server before retrying the
|
2007-04-12 22:42:49 +00:00
|
|
|
query via a different name server.
|
|
|
|
|
Measured in seconds,
|
2007-12-16 14:23:16 +00:00
|
|
|
the default is
|
|
|
|
|
.BR RES_TIMEOUT
|
|
|
|
|
(currently 5, see \fI<resolv.h>\fP).
|
2009-09-27 07:26:38 +00:00
|
|
|
The value for this option is silently capped to 30.
|
2004-11-03 13:51:07 +00:00
|
|
|
.TP
|
|
|
|
|
.BI attempts: n
|
|
|
|
|
sets the number of times the resolver will send a
|
|
|
|
|
query to its name servers before giving up and returning
|
2007-04-12 22:42:49 +00:00
|
|
|
an error to the calling application.
|
2007-12-16 14:23:16 +00:00
|
|
|
The default is
|
|
|
|
|
.BR RES_DFLRETRY
|
|
|
|
|
(currently 2, see \fI<resolv.h>\fP).
|
2009-09-27 07:26:38 +00:00
|
|
|
The value for this option is silently capped to 5.
|
2004-11-03 13:51:07 +00:00
|
|
|
.TP
|
|
|
|
|
.B rotate
|
2009-02-28 19:37:19 +00:00
|
|
|
.\" Since glibc 2.2
|
2007-12-16 14:23:16 +00:00
|
|
|
sets
|
|
|
|
|
.BR RES_ROTATE
|
|
|
|
|
in
|
2004-11-03 13:51:07 +00:00
|
|
|
.IR _res.options ,
|
2014-01-15 04:47:31 +00:00
|
|
|
which causes round-robin selection of name servers from among those listed.
|
2004-11-03 13:51:07 +00:00
|
|
|
This has the effect of spreading the query load among all listed servers,
|
|
|
|
|
rather than having all clients try the first listed server first every time.
|
|
|
|
|
.TP
|
|
|
|
|
.B no-check-names
|
2009-02-28 19:37:19 +00:00
|
|
|
.\" since glibc 2.2
|
2007-12-16 14:23:16 +00:00
|
|
|
sets
|
|
|
|
|
.BR RES_NOCHECKNAME
|
|
|
|
|
in
|
2004-11-03 13:51:07 +00:00
|
|
|
.IR _res.options ,
|
2008-06-27 03:37:56 +00:00
|
|
|
which disables the modern BIND checking of incoming hostnames and
|
2004-11-03 13:51:07 +00:00
|
|
|
mail names for invalid characters such as underscore (_), non-ASCII,
|
|
|
|
|
or control characters.
|
|
|
|
|
.TP
|
|
|
|
|
.B inet6
|
2009-02-28 19:37:19 +00:00
|
|
|
.\" Since glibc 2.2
|
2007-12-16 14:23:16 +00:00
|
|
|
sets
|
|
|
|
|
.BR RES_USE_INET6
|
|
|
|
|
in
|
2004-11-03 13:51:07 +00:00
|
|
|
.IR _res.options .
|
|
|
|
|
This has the effect of trying a AAAA query before an A query inside the
|
2007-06-02 06:22:00 +00:00
|
|
|
.BR gethostbyname (3)
|
2007-12-16 14:08:46 +00:00
|
|
|
function, and of mapping IPv4 responses in IPv6 "tunneled form"
|
2004-11-03 13:51:07 +00:00
|
|
|
if no AAAA records are found but an A record set exists.
|
2009-02-28 19:17:01 +00:00
|
|
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.TP
|
2009-02-28 21:04:52 +00:00
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|
.BR ip6-bytestring " (since glibc 2.3.4)"
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|
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|
sets
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|
.BR RES_USE_BSTRING
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in
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.IR _res.options .
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|
This causes reverse IPv6 lookups to be made using the bit-label format
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|
described in RFC\ 2673;
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|
if this option is not set, then nibble format is used.
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|
.TP
|
2009-02-28 21:23:53 +00:00
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|
.BR ip6-dotint / no-ip6-dotint " (since glibc 2.3.4)"
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|
Clear/set
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.BR RES_NOIP6DOTINT
|
|
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in
|
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|
.IR _res.options .
|
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When this option is clear
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.RB ( ip6-dotint ),
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|
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|
reverse IPv6 lookups are made in the (deprecated)
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|
.I ip6.int
|
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|
zone;
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|
when this option is set
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|
.RB ( no-ip6-dotint ),
|
|
|
|
|
reverse IPv6 lookups are made in the
|
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|
.I ip6.arpa
|
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|
zone by default.
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|
This option is set by default.
|
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|
.TP
|
2009-02-28 19:17:01 +00:00
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|
|
.BR edns0 " (since glibc 2.6)"
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|
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|
sets
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|
.BR RES_USE_EDNSO
|
|
|
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|
in
|
|
|
|
|
.IR _res.options .
|
|
|
|
|
This enables support for the DNS extensions described in RFC\ 2671.
|
2012-04-23 12:11:11 +00:00
|
|
|
.TP
|
|
|
|
|
.BR single-request " (since glibc 2.10)"
|
|
|
|
|
sets
|
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|
|
.BR RES_SNGLKUP
|
|
|
|
|
in
|
|
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|
|
.IR _res.options .
|
|
|
|
|
By default, glibc performs IPv4 and IPv6 lookups in parallel since
|
|
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|
|
version 2.9.
|
|
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|
|
Some appliance DNS servers
|
|
|
|
|
cannot handle these queries properly and make the requests time out.
|
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|
This option disables the behavior and makes glibc perform the IPv6
|
|
|
|
|
and IPv4 requests sequentially (at the cost of some slowdown of the
|
|
|
|
|
resolving process).
|
2013-02-10 03:21:34 +00:00
|
|
|
.TP
|
|
|
|
|
.BR single-request-reopen " (since glibc 2.9)"
|
2013-02-12 02:52:40 +00:00
|
|
|
The resolver uses the same socket for the A and AAAA requests.
|
intro.1, _syscall.2, access.2, arch_prctl.2, cacheflush.2, chown.2, clock_getres.2, clone.2, create_module.2, fcntl.2, flock.2, get_kernel_syms.2, get_robust_list.2, get_thread_area.2, getcpu.2, getpriority.2, getrlimit.2, getrusage.2, ioprio_set.2, kexec_load.2, madvise.2, mbind.2, migrate_pages.2, mknod.2, mmap.2, mount.2, move_pages.2, mprotect.2, open.2, pause.2, pciconfig_read.2, perf_event_open.2, prctl.2, ptrace.2, query_module.2, read.2, reboot.2, recv.2, s390_runtime_instr.2, sched_setscheduler.2, select_tut.2, send.2, set_mempolicy.2, setfsgid.2, setfsuid.2, sigaction.2, spu_create.2, spu_run.2, stime.2, swapon.2, syslog.2, timer_create.2, timer_getoverrun.2, times.2, tkill.2, umount.2, unimplemented.2, ustat.2, vm86.2, wait.2, abs.3, aio_read.3, aio_write.3, bsd_signal.3, catgets.3, clearenv.3, cmsg.3, dbopen.3, dirfd.3, dlopen.3, exec.3, fenv.3, ferror.3, fmemopen.3, fnmatch.3, fopen.3, futimes.3, getaddrinfo.3, getifaddrs.3, getipnodebyname.3, hsearch.3, if_nameindex.3, inet_pton.3, mblen.3, mbrlen.3, mbsrtowcs.3, mbtowc.3, mcheck.3, memfrob.3, mq_notify.3, netlink.3, posix_memalign.3, printf.3, pthread_attr_setscope.3, pthread_cleanup_push.3, pthread_kill_other_threads_np.3, pthread_self.3, pthread_setcancelstate.3, pthread_setconcurrency.3, raise.3, resolver.3, rpc.3, rtime.3, rtnetlink.3, scanf.3, setbuf.3, setnetgrent.3, shm_open.3, sigpause.3, sigset.3, sigwait.3, sockatmark.3, strcasecmp.3, strcmp.3, strdup.3, strftime.3, strptime.3, strsignal.3, strverscmp.3, sysv_signal.3, termios.3, wcrtomb.3, wcsnlen.3, wcsnrtombs.3, wcsrtombs.3, wctomb.3, wprintf.3, console_codes.4, cpuid.4, msr.4, rtc.4, sk98lin.4, st.4, tty.4, charmap.5, core.5, elf.5, hosts.equiv.5, proc.5, resolv.conf.5, services.5, slabinfo.5, arp.7, bootparam.7, capabilities.7, charsets.7, cpuset.7, ddp.7, epoll.7, feature_test_macros.7, futex.7, hier.7, icmp.7, inotify.7, ip.7, ipv6.7, man-pages.7, mdoc.7, mdoc.samples.7, netdevice.7, netlink.7, numa.7, packet.7, path_resolution.7, posixoptions.7, pthreads.7, raw.7, rtld-audit.7, rtnetlink.7, sem_overview.7, sigevent.7, socket.7, spufs.7, tcp.7, udp.7, unicode.7, uri.7, utf-8.7, intro.8, ldconfig.8, sync.8: Global fix: fix placement of word "only"
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
2013-03-31 08:53:00 +00:00
|
|
|
Some hardware mistakenly sends back only one reply.
|
2013-02-12 02:52:40 +00:00
|
|
|
When that happens the client system will sit and wait for the second reply.
|
|
|
|
|
Turning this option on changes this behavior
|
2013-02-10 03:21:34 +00:00
|
|
|
so that if two requests from the same port are not handled correctly it will
|
2014-05-11 07:04:13 +00:00
|
|
|
close the socket and open a new one before sending the second request.
|
2014-10-16 10:49:13 +00:00
|
|
|
.TP
|
|
|
|
|
.BR no-tld-query " (since glibc 2.14)"
|
|
|
|
|
sets RES_NOTLDQUERY in
|
|
|
|
|
.IR _res.options .
|
|
|
|
|
This option causes
|
|
|
|
|
.BR res_nsearch()
|
|
|
|
|
to not attempt to resolve an unqualified name
|
|
|
|
|
as if it were a top level domain (TLD).
|
|
|
|
|
This option can cause problems if the site has ``localhost'' as a TLD
|
|
|
|
|
rather than having localhost on one or more elements of the search list.
|
|
|
|
|
This option has no effect if neither RES_DEFNAMES or RES_DNSRCH is set.
|
2004-11-03 13:51:07 +00:00
|
|
|
.RE
|
|
|
|
|
.LP
|
|
|
|
|
The \fIdomain\fP and \fIsearch\fP keywords are mutually exclusive.
|
|
|
|
|
If more than one instance of these keywords is present,
|
|
|
|
|
the last instance wins.
|
|
|
|
|
.LP
|
|
|
|
|
The \fIsearch\fP keyword of a system's \fIresolv.conf\fP file can be
|
|
|
|
|
overridden on a per-process basis by setting the environment variable
|
2007-12-16 14:08:46 +00:00
|
|
|
.B LOCALDOMAIN
|
|
|
|
|
to a space-separated list of search domains.
|
2004-11-03 13:51:07 +00:00
|
|
|
.LP
|
|
|
|
|
The \fIoptions\fP keyword of a system's \fIresolv.conf\fP file can be
|
|
|
|
|
amended on a per-process basis by setting the environment variable
|
2007-12-16 14:08:46 +00:00
|
|
|
.B RES_OPTIONS
|
|
|
|
|
to a space-separated list of resolver options
|
2004-11-03 13:51:07 +00:00
|
|
|
as explained above under \fBoptions\fP.
|
|
|
|
|
.LP
|
|
|
|
|
The keyword and value must appear on a single line, and the keyword
|
2007-06-08 11:56:22 +00:00
|
|
|
(e.g., \fBnameserver\fP) must start the line.
|
2007-04-12 22:42:49 +00:00
|
|
|
The value follows the keyword, separated by white space.
|
2012-02-07 18:20:42 +00:00
|
|
|
|
|
|
|
|
Lines that contain a semicolon (;) or hash character (#)
|
|
|
|
|
in the first column are treated as comments.
|
2004-11-03 13:51:07 +00:00
|
|
|
.SH FILES
|
|
|
|
|
.IR /etc/resolv.conf ,
|
|
|
|
|
.I <resolv.h>
|
getent.1, intro.1, time.1, _exit.2, _syscall.2, accept.2, access.2, acct.2, adjtimex.2, alarm.2, alloc_hugepages.2, arch_prctl.2, bdflush.2, bind.2, brk.2, cacheflush.2, capget.2, chdir.2, chmod.2, chown.2, chroot.2, clock_getres.2, clock_nanosleep.2, clone.2, close.2, connect.2, create_module.2, delete_module.2, dup.2, epoll_create.2, epoll_ctl.2, epoll_wait.2, eventfd.2, execve.2, exit_group.2, faccessat.2, fchmodat.2, fchownat.2, fcntl.2, flock.2, fork.2, fstatat.2, fsync.2, futex.2, futimesat.2, get_kernel_syms.2, get_robust_list.2, get_thread_area.2, getcpu.2, getdents.2, getdomainname.2, getgid.2, getgroups.2, gethostname.2, getitimer.2, getpagesize.2, getpeername.2, getpid.2, getpriority.2, getresuid.2, getrlimit.2, getrusage.2, getsid.2, getsockname.2, getsockopt.2, gettid.2, gettimeofday.2, getuid.2, getunwind.2, getxattr.2, idle.2, init_module.2, inotify_add_watch.2, inotify_init.2, inotify_rm_watch.2, intro.2, io_cancel.2, io_destroy.2, io_getevents.2, io_setup.2, io_submit.2, ioctl.2, ioctl_list.2, ioperm.2, iopl.2, ioprio_set.2, ipc.2, kcmp.2, kill.2, killpg.2, link.2, linkat.2, listen.2, listxattr.2, llseek.2, lookup_dcookie.2, lseek.2, madvise.2, migrate_pages.2, mincore.2, mkdir.2, mkdirat.2, mknod.2, mknodat.2, mlock.2, mmap.2, mmap2.2, modify_ldt.2, mount.2, move_pages.2, mprotect.2, mq_getsetattr.2, mremap.2, msgctl.2, msgget.2, msgop.2, msync.2, nanosleep.2, nfsservctl.2, nice.2, open.2, openat.2, outb.2, pause.2, pciconfig_read.2, perf_event_open.2, perfmonctl.2, personality.2, pipe.2, pivot_root.2, poll.2, posix_fadvise.2, prctl.2, pread.2, process_vm_readv.2, ptrace.2, query_module.2, quotactl.2, read.2, readahead.2, readdir.2, readlink.2, readlinkat.2, readv.2, reboot.2, recv.2, remap_file_pages.2, removexattr.2, rename.2, renameat.2, rmdir.2, rt_sigqueueinfo.2, sched_get_priority_max.2, sched_rr_get_interval.2, sched_setaffinity.2, sched_setparam.2, sched_setscheduler.2, sched_yield.2, select.2, semctl.2, semget.2, semop.2, send.2, sendfile.2, set_thread_area.2, set_tid_address.2, seteuid.2, setfsgid.2, setfsuid.2, setgid.2, setpgid.2, setresuid.2, setreuid.2, setsid.2, setuid.2, setup.2, setxattr.2, shmctl.2, shmget.2, shmop.2, shutdown.2, sigaction.2, sigaltstack.2, signal.2, signalfd.2, sigpending.2, sigprocmask.2, sigreturn.2, sigsuspend.2, sigwaitinfo.2, socket.2, socketcall.2, socketpair.2, splice.2, stat.2, statfs.2, stime.2, swapon.2, symlink.2, symlinkat.2, sync.2, sync_file_range.2, sysctl.2, sysfs.2, sysinfo.2, syslog.2, tee.2, time.2, timerfd_create.2, times.2, tkill.2, truncate.2, umask.2, umount.2, uname.2, unimplemented.2, unlink.2, unlinkat.2, uselib.2, ustat.2, utime.2, utimensat.2, vfork.2, vhangup.2, vm86.2, vmsplice.2, wait.2, wait4.2, write.2, CPU_SET.3, INFINITY.3, MB_CUR_MAX.3, MB_LEN_MAX.3, __setfpucw.3, a64l.3, abort.3, abs.3, acos.3, acosh.3, addseverity.3, adjtime.3, aio_cancel.3, aio_error.3, aio_fsync.3, aio_read.3, aio_return.3, aio_suspend.3, aio_write.3, alloca.3, argz_add.3, asin.3, asinh.3, asprintf.3, assert.3, assert_perror.3, atan.3, atan2.3, atanh.3, atexit.3, atof.3, atoi.3, backtrace.3, basename.3, bcmp.3, bcopy.3, bindresvport.3, bsd_signal.3, bsearch.3, bstring.3, btowc.3, btree.3, byteorder.3, bzero.3, cabs.3, cacos.3, cacosh.3, canonicalize_file_name.3, carg.3, casin.3, casinh.3, catan.3, catanh.3, catgets.3, catopen.3, cbrt.3, ccos.3, ccosh.3, ceil.3, cerf.3, cexp.3, cexp2.3, cfree.3, cimag.3, clearenv.3, clock.3, clock_getcpuclockid.3, clog.3, clog10.3, clog2.3, closedir.3, cmsg.3, confstr.3, conj.3, copysign.3, cos.3, cosh.3, cpow.3, cproj.3, creal.3, crypt.3, csin.3, csinh.3, csqrt.3, ctan.3, ctanh.3, ctermid.3, ctime.3, daemon.3, dbopen.3, des_crypt.3, difftime.3, dirfd.3, div.3, dl_iterate_phdr.3, dlopen.3, dprintf.3, drand48.3, drand48_r.3, dysize.3, ecvt.3, ecvt_r.3, encrypt.3, end.3, endian.3, envz_add.3, erf.3, erfc.3, err.3, errno.3, error.3, ether_aton.3, euidaccess.3, exec.3, exit.3, exp.3, exp10.3, exp2.3, expm1.3, fabs.3, fclose.3, fcloseall.3, fdim.3, fenv.3, ferror.3, fexecve.3, fflush.3, ffs.3, fgetgrent.3, fgetpwent.3, fgetwc.3, fgetws.3, finite.3, flockfile.3, floor.3, fma.3, fmax.3, fmemopen.3, fmin.3, fmod.3, fmtmsg.3, fnmatch.3, fopen.3, fpathconf.3, fpclassify.3, fpurge.3, fputwc.3, fputws.3, fread.3, frexp.3, fseek.3, fseeko.3, ftime.3, ftok.3, fts.3, ftw.3, futimes.3, fwide.3, gamma.3, gcvt.3, getaddrinfo.3, getaddrinfo_a.3, getauxval.3, getcontext.3, getcwd.3, getdate.3, getdirentries.3, getdtablesize.3, getenv.3, getfsent.3, getgrent.3, getgrent_r.3, getgrnam.3, getgrouplist.3, gethostbyname.3, gethostid.3, getipnodebyname.3, getline.3, getloadavg.3, getlogin.3, getmntent.3, getnameinfo.3, getnetent.3, getnetent_r.3, getopt.3, getpass.3, getprotoent.3, getprotoent_r.3, getpt.3, getpw.3, getpwent.3, getpwent_r.3, getpwnam.3, getrpcent.3, getrpcent_r.3, getrpcport.3, gets.3, getservent.3, getservent_r.3, getspnam.3, getttyent.3, getumask.3, getusershell.3, getutent.3, getw.3, getwchar.3, glob.3, grantpt.3, gsignal.3, hash.3, hsearch.3, hypot.3, iconv.3, iconv_close.3, iconv_open.3, ilogb.3, index.3, inet.3, inet_ntop.3, inet_pton.3, infnan.3, initgroups.3, insque.3, intro.3, isalpha.3, isatty.3, isgreater.3, iswalnum.3, iswalpha.3, iswblank.3, iswcntrl.3, iswctype.3, iswdigit.3, iswgraph.3, iswlower.3, iswprint.3, iswpunct.3, iswspace.3, iswupper.3, iswxdigit.3, j0.3, key_setsecret.3, ldexp.3, lgamma.3, lio_listio.3, localeconv.3, lockf.3, log.3, log10.3, log1p.3, log2.3, logb.3, login.3, longjmp.3, lrint.3, lround.3, lsearch.3, lseek64.3, makecontext.3, makedev.3, malloc.3, malloc_hook.3, mblen.3, mbrlen.3, mbrtowc.3, mbsinit.3, mbsnrtowcs.3, mbsrtowcs.3, mbstowcs.3, mbtowc.3, memccpy.3, memchr.3, memcmp.3, memcpy.3, memfrob.3, memmem.3, memmove.3, mempcpy.3, memset.3, mkdtemp.3, mkfifo.3, mkfifoat.3, mkstemp.3, mktemp.3, modf.3, mpool.3, mq_close.3, mq_getattr.3, mq_notify.3, mq_open.3, mq_receive.3, mq_send.3, mq_unlink.3, mtrace.3, nan.3, netlink.3, nextafter.3, nl_langinfo.3, offsetof.3, on_exit.3, opendir.3, openpty.3, perror.3, popen.3, posix_fallocate.3, posix_memalign.3, posix_openpt.3, pow.3, pow10.3, printf.3, profil.3, program_invocation_name.3, psignal.3, pthread_kill_other_threads_np.3, ptsname.3, putenv.3, putgrent.3, putpwent.3, puts.3, putwchar.3, qecvt.3, qsort.3, queue.3, raise.3, rand.3, random.3, random_r.3, rcmd.3, re_comp.3, readdir.3, realpath.3, recno.3, regex.3, remainder.3, remove.3, remquo.3, resolver.3, rewinddir.3, rexec.3, rint.3, round.3, rpc.3, rpmatch.3, rtime.3, rtnetlink.3, scalb.3, scalbln.3, scandir.3, scandirat.3, scanf.3, seekdir.3, sem_close.3, sem_destroy.3, sem_getvalue.3, sem_init.3, sem_open.3, sem_post.3, sem_unlink.3, sem_wait.3, setaliasent.3, setbuf.3, setenv.3, setjmp.3, setlocale.3, setlogmask.3, setnetgrent.3, shm_open.3, siginterrupt.3, signbit.3, significand.3, sigpause.3, sigqueue.3, sigset.3, sigsetops.3, sigvec.3, sin.3, sincos.3, sinh.3, sleep.3, sockatmark.3, sqrt.3, statvfs.3, stdarg.3, stdin.3, stdio.3, stdio_ext.3, stpcpy.3, stpncpy.3, strcasecmp.3, strcat.3, strchr.3, strcmp.3, strcoll.3, strcpy.3, strdup.3, strerror.3, strfmon.3, strfry.3, strftime.3, string.3, strlen.3, strnlen.3, strpbrk.3, strptime.3, strsep.3, strsignal.3, strspn.3, strstr.3, strtod.3, strtoimax.3, strtok.3, strtol.3, strtoul.3, strverscmp.3, strxfrm.3, swab.3, sysconf.3, syslog.3, system.3, sysv_signal.3, tan.3, tanh.3, tcgetpgrp.3, tcgetsid.3, telldir.3, tempnam.3, termios.3, tgamma.3, timegm.3, timeradd.3, tmpfile.3, tmpnam.3, toascii.3, toupper.3, towctrans.3, towlower.3, towupper.3, trunc.3, tsearch.3, ttyname.3, ttyslot.3, tzset.3, ualarm.3, ulimit.3, ungetwc.3, unlocked_stdio.3, unlockpt.3, updwtmp.3, usleep.3, wcpcpy.3, wcpncpy.3, wcrtomb.3, wcscasecmp.3, wcscat.3, wcschr.3, wcscmp.3, wcscpy.3, wcscspn.3, wcsdup.3, wcslen.3, wcsncasecmp.3, wcsncat.3, wcsncmp.3, wcsncpy.3, wcsnlen.3, wcsnrtombs.3, wcspbrk.3, wcsrchr.3, wcsrtombs.3, wcsspn.3, wcsstr.3, wcstoimax.3, wcstok.3, wcstombs.3, wcswidth.3, wctob.3, wctomb.3, wctrans.3, wctype.3, wcwidth.3, wmemchr.3, wmemcmp.3, wmemcpy.3, wmemmove.3, wmemset.3, wordexp.3, wprintf.3, xcrypt.3, xdr.3, y0.3, cciss.4, console.4, console_codes.4, console_ioctl.4, dsp56k.4, fd.4, full.4, hd.4, hpsa.4, initrd.4, intro.4, lp.4, mem.4, mouse.4, null.4, pts.4, ram.4, random.4, rtc.4, sk98lin.4, st.4, tty.4, ttyS.4, tty_ioctl.4, vcs.4, wavelan.4, acct.5, charmap.5, dir_colors.5, filesystems.5, ftpusers.5, group.5, host.conf.5, hosts.5, hosts.equiv.5, intro.5, issue.5, locale.5, motd.5, networks.5, nologin.5, nscd.conf.5, passwd.5, proc.5, protocols.5, resolv.conf.5, rpc.5, securetty.5, services.5, shells.5, termcap.5, ttytype.5, utmp.5, armscii-8.7, arp.7, ascii.7, bootparam.7, capabilities.7, charsets.7, complex.7, cp1251.7, credentials.7, ddp.7, environ.7, epoll.7, fifo.7, futex.7, glob.7, hier.7, icmp.7, inotify.7, intro.7, ip.7, ipv6.7, iso_8859-1.7, iso_8859-10.7, iso_8859-11.7, iso_8859-13.7, iso_8859-14.7, iso_8859-15.7, iso_8859-16.7, iso_8859-2.7, iso_8859-3.7, iso_8859-4.7, iso_8859-5.7, iso_8859-6.7, iso_8859-7.7, iso_8859-8.7, iso_8859-9.7, koi8-r.7, koi8-u.7, locale.7, mailaddr.7, man.7, mq_overview.7, netdevice.7, netlink.7, numa.7, packet.7, path_resolution.7, pipe.7, posixoptions.7, pthreads.7, pty.7, raw.7, regex.7, rtld-audit.7, rtnetlink.7, sem_overview.7, shm_overview.7, sigevent.7, signal.7, socket.7, standards.7, suffixes.7, svipc.7, tcp.7, termio.7, time.7, udp.7, udplite.7, unicode.7, unix.7, uri.7, utf-8.7, x25.7, nscd.8, sync.8, tzselect.8, zdump.8, zic.8: Global fix: remove unneeded double quotes in .SH headings
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
2013-02-24 18:01:36 +00:00
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.SH SEE ALSO
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2004-11-03 13:51:07 +00:00
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.BR gethostbyname (3),
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.BR resolver (3),
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.BR hostname (7),
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.BR named (8)
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.br
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Name Server Operations Guide for BIND
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