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Diffstat (limited to 'static/netbsd/man7/hostname.7')
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diff --git a/static/netbsd/man7/hostname.7 b/static/netbsd/man7/hostname.7 new file mode 100644 index 00000000..38bab06a --- /dev/null +++ b/static/netbsd/man7/hostname.7 @@ -0,0 +1,185 @@ +.\" $NetBSD: hostname.7,v 1.13 2012/03/29 18:37:21 wiz Exp $ +.\" +.\" Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC") +.\" +.\" Permission to use, copy, modify, and distribute this software for any +.\" purpose with or without fee is hereby granted, provided that the above +.\" copyright notice and this permission notice appear in all copies. +.\" +.\" THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES +.\" WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF +.\" MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR +.\" ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES +.\" WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN +.\" ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT +.\" OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. +.\" +.\" Copyright (c) 1987 The Regents of the University of California. +.\" All rights reserved. +.\" +.\" Redistribution and use in source and binary forms are permitted +.\" provided that the above copyright notice and this paragraph are +.\" duplicated in all such forms and that any documentation, +.\" advertising materials, and other materials related to such +.\" distribution and use acknowledge that the software was developed +.\" by the University of California, Berkeley. The name of the +.\" University may not be used to endorse or promote products derived +.\" from this software without specific prior written permission. +.\" THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR +.\" IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED +.\" WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. +.\" +.\" @(#)hostname.7 6.4 (Berkeley) 1/16/90 +.\" +.Dd February 16, 1994 +.Dt HOSTNAME 7 +.Os +.Sh NAME +.Nm hostname +.Nd host name resolution description +.Sh DESCRIPTION +Hostnames are domains. +A domain is a hierarchical, dot-separated list of subdomains. +For example, the machine +.Dq Li monet , +in the +.Dq Li Berkeley +subdomain of the +.Dq Li EDU +subdomain of the Internet Domain Name System would be represented as +.Pp +.Dl monet.Berkeley.EDU +.Pp +(with no trailing dot). +.Pp +Hostnames are often used with network client and server programs, +which must generally translate the name to an address for use. +(This task is usually performed by the library routine +.Xr gethostbyname 3 . ) +The default method for resolving hostnames by the Internet name resolver is +to follow RFC 1535's security recommendations. +Actions can be taken by the administrator to override these +recommendations and to have the resolver behave the same as earlier, +non-RFC 1535 resolvers. +.Pp +The default method (using RFC 1535 guidelines) follows: +.Pp +If the name consists of a single component, i.e. contains no dot, and if the +environment variable +.Dq Ev HOSTALIASES +is set to the name of a file, +that file is searched for a string matching the input hostname. +The file +should consist of lines made up of two strings separated by white-space, the +first of which is the hostname alias, and the second of which is the complete +hostname to be substituted for that alias. +If a case-insensitive match is +found between the hostname to be resolved and the first field of a line in +the file, the substituted name is looked up with no further processing. +.Pp +If there is at least one dot in the name, then the name is first tried +.Dq as-is . +The number of dots to cause this action is configurable by setting the +threshold using the +.Dq Li ndots +option in +.Pa /etc/resolv.conf +(default: 1). +If the name ends with a dot, the trailing dot is +removed, and the remaining name is looked up (regardless of the setting of +the +.Li ndots +option), without further processing. +.Pp +If the input name does not end with a trailing dot, it is looked up by +searching through a list of domains until a match is found. +If neither the search option in the +.Pa /etc/resolv.conf +file or the +.Dq Ev LOCALDOMAIN +environment variable is used, then the +search list of domains contains only the full domain specified by the +.Li domain +option (in +.Pa /etc/resolv.conf ) +or the domain used in the local hostname. +For example, if the +.Dq Li domain +option is set to +.Li CS.Berkeley.EDU , +then only +.Li CS.Berkeley.EDU +will be in the search list, and this will be the only +domain appended to the partial hostname. +For example, if +.Dq Li lithium +is the name to be resolved, this would make +.Li lithium.CS.Berkeley.EDU +the only name to be tried using the search list. +.Pp +If the +.Li search +option is used in +.Pa /etc/resolv.conf +or the environment variable +.Dq Ev LOCALDOMAIN +is set by the user, then +the search list will include what is set by these methods. +For example, if the +.Dq Li search +option contained +.Pp +.Dl CS.Berkeley.EDU CChem.Berkeley.EDU Berkeley.EDU +.Pp +then the partial hostname (e.g., +.Dq Li lithium ) +will be tried with +.Em each +domain name appended (in the same order specified); the resulting hostnames +that would be tried are: +.Bd -literal -offset indent +lithium.CS.Berkeley.EDU +lithium.CChem.Berkeley.EDU +lithium.Berkeley.EDU +.Ed +.Pp +The environment variable +.Dq Ev LOCALDOMAIN +overrides the +.Dq Li search +and +.Dq Li domain +options, and if both +.Li search +and +.Li domain +options are present in the resolver configuration file, then only the +.Em last +one listed is used (see +.Xr resolv.conf 5 ) . +.Pp +If the name was not previously tried +.Dq as-is +(i.e., it fell below the +.Dq Li ndots +threshold or did not contain a dot), then the name as +originally provided is attempted. +.Sh ENVIRONMENT +.Bl -tag -width "/etc/resolv.conf " +.It Ev LOCALDOMAIN +Affects domains appended to partial hostnames. +.It Ev HOSTALIASES +Name of file containing +.Pq Ar host alias , full hostname +pairs. +.El +.Sh FILES +.Bl -tag -width "/etc/resolv.conf " -compact +.It Pa /etc/resolv.conf +See +.Xr resolv.conf 5 . +.El +.Sh SEE ALSO +.Xr gethostbyname 3 , +.Xr resolv.conf 5 , +.Xr mailaddr 7 |