1996-08-30 19:40:05 +00:00
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.\" Copyright (c) 1983, 1987, 1991, 1993
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.\" The Regents of the University of California. All rights reserved.
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1996-08-29 22:13:00 +00:00
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.\"
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1996-08-30 19:40:05 +00:00
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.\" Redistribution and use in source and binary forms, with or without
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.\" modification, are permitted provided that the following conditions
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.\" are met:
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.\" 1. Redistributions of source code must retain the above copyright
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.\" notice, this list of conditions and the following disclaimer.
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.\" 2. Redistributions in binary form must reproduce the above copyright
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.\" notice, this list of conditions and the following disclaimer in the
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.\" documentation and/or other materials provided with the distribution.
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.\" 3. All advertising materials mentioning features or use of this software
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.\" must display the following acknowledgement:
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.\" This product includes software developed by the University of
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.\" California, Berkeley and its contributors.
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.\" 4. Neither the name of the University nor the names of its contributors
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.\" may be used to endorse or promote products derived from this software
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.\" without specific prior written permission.
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1996-08-29 22:13:00 +00:00
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.\"
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1996-08-30 19:40:05 +00:00
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.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
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.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
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.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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.\" SUCH DAMAGE.
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1996-08-29 22:13:00 +00:00
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.\"
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1997-06-18 06:26:13 +00:00
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.\" From: @(#)gethostbyname.3 8.4 (Berkeley) 5/25/95
|
1999-08-28 00:22:10 +00:00
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.\" $FreeBSD$
|
1996-08-30 19:40:05 +00:00
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.\"
|
1996-11-01 06:29:00 +00:00
|
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|
.Dd May 25, 1995
|
1996-08-30 19:40:05 +00:00
|
|
|
.Dt GETHOSTBYNAME 3
|
2001-07-10 13:41:46 +00:00
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|
|
.Os
|
1996-08-30 19:40:05 +00:00
|
|
|
.Sh NAME
|
|
|
|
.Nm gethostbyname ,
|
1996-11-01 06:29:00 +00:00
|
|
|
.Nm gethostbyname2 ,
|
1996-08-30 19:40:05 +00:00
|
|
|
.Nm gethostbyaddr ,
|
|
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|
.Nm gethostent ,
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.Nm sethostent ,
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.Nm endhostent ,
|
1996-11-01 06:29:00 +00:00
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|
.Nm herror ,
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|
|
|
.Nm hstrerror
|
1996-08-30 19:40:05 +00:00
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.Nd get network host entry
|
2000-04-21 09:42:15 +00:00
|
|
|
.Sh LIBRARY
|
|
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|
.Lb libc
|
1996-08-30 19:40:05 +00:00
|
|
|
.Sh SYNOPSIS
|
2001-10-01 16:09:29 +00:00
|
|
|
.In netdb.h
|
2001-01-12 15:46:56 +00:00
|
|
|
.Vt extern int h_errno ;
|
1996-08-30 19:40:05 +00:00
|
|
|
.Ft struct hostent *
|
1996-10-08 22:30:08 +00:00
|
|
|
.Fn gethostbyname "const char *name"
|
1996-08-30 19:40:05 +00:00
|
|
|
.Ft struct hostent *
|
1996-11-01 06:29:00 +00:00
|
|
|
.Fn gethostbyname2 "const char *name" "int af"
|
|
|
|
.Ft struct hostent *
|
1996-10-08 22:30:08 +00:00
|
|
|
.Fn gethostbyaddr "const char *addr" "int len" "int type"
|
1996-08-30 19:40:05 +00:00
|
|
|
.Ft struct hostent *
|
|
|
|
.Fn gethostent void
|
1997-03-19 00:32:42 +00:00
|
|
|
.Ft void
|
1996-08-30 19:40:05 +00:00
|
|
|
.Fn sethostent "int stayopen"
|
1997-03-19 00:32:42 +00:00
|
|
|
.Ft void
|
1996-08-30 19:40:05 +00:00
|
|
|
.Fn endhostent void
|
1997-03-19 00:32:42 +00:00
|
|
|
.Ft void
|
1996-10-08 22:30:08 +00:00
|
|
|
.Fn herror "const char *string"
|
1996-11-01 06:29:00 +00:00
|
|
|
.Ft const char *
|
|
|
|
.Fn hstrerror "int err"
|
1996-08-30 19:40:05 +00:00
|
|
|
.Sh DESCRIPTION
|
2001-08-08 11:05:47 +00:00
|
|
|
.Bf -symbolic
|
|
|
|
The
|
|
|
|
.Xr getaddrinfo 3
|
|
|
|
and
|
|
|
|
.Xr getnameinfo 3
|
|
|
|
functions are preferred over the
|
|
|
|
.Fn gethostbyname ,
|
|
|
|
.Fn gethostbyname2 ,
|
|
|
|
and
|
|
|
|
.Fn gethostbyaddr
|
|
|
|
functions.
|
|
|
|
.Ef
|
|
|
|
.Pp
|
1996-08-30 19:40:05 +00:00
|
|
|
The
|
1996-11-01 06:29:00 +00:00
|
|
|
.Fn gethostbyname ,
|
|
|
|
.Fn gethostbyname2
|
1996-08-29 22:13:00 +00:00
|
|
|
and
|
1996-08-30 19:40:05 +00:00
|
|
|
.Fn gethostbyaddr
|
|
|
|
functions
|
1996-08-29 22:13:00 +00:00
|
|
|
each return a pointer to an object with the
|
|
|
|
following structure describing an internet host
|
|
|
|
referenced by name or by address, respectively.
|
2001-02-09 19:06:25 +00:00
|
|
|
.Pp
|
|
|
|
The
|
|
|
|
.Fa name
|
2002-12-19 09:40:28 +00:00
|
|
|
argument passed to
|
2001-02-09 19:06:25 +00:00
|
|
|
.Fn gethostbyname
|
|
|
|
or
|
|
|
|
.Fn gethostbyname2
|
2001-02-10 10:51:39 +00:00
|
|
|
should point to a
|
|
|
|
.Dv NUL Ns -terminated
|
|
|
|
hostname.
|
2001-02-09 19:06:25 +00:00
|
|
|
The
|
|
|
|
.Fa addr
|
2002-12-19 09:40:28 +00:00
|
|
|
argument passed to
|
2001-02-09 19:06:25 +00:00
|
|
|
.Fn gethostbyaddr
|
|
|
|
should point to an address which is
|
|
|
|
.Fa len
|
|
|
|
bytes long,
|
|
|
|
in binary form
|
2001-02-10 10:51:39 +00:00
|
|
|
(i.e. not an IP address in human readable
|
|
|
|
.Tn ASCII
|
|
|
|
form).
|
2001-02-09 19:06:25 +00:00
|
|
|
The
|
|
|
|
.Fa type
|
2002-12-19 09:40:28 +00:00
|
|
|
argument specifies the address family
|
2001-02-10 10:51:39 +00:00
|
|
|
(e.g.\&
|
|
|
|
.Dv AF_INET , AF_INET6 ,
|
|
|
|
etc.) of this address.
|
2001-02-09 19:06:25 +00:00
|
|
|
.Pp
|
|
|
|
The structure returned contains either the information obtained from the name
|
|
|
|
server,
|
1996-08-30 19:40:05 +00:00
|
|
|
.Xr named 8 ,
|
Add nsswitch support. By creating an /etc/nsswitch.conf file, you can
configure FreeBSD so that various databases such as passwd and group can be
looked up using flat files, NIS, or Hesiod.
= Hesiod has been added to libc (see hesiod(3)).
= A library routine for parsing nsswitch.conf and invoking callback
functions as specified has been added to libc (see nsdispatch(3)).
= The following C library functions have been modified to use nsdispatch:
. getgrent, getgrnam, getgrgid
. getpwent, getpwnam, getpwuid
. getusershell
. getaddrinfo
. gethostbyname, gethostbyname2, gethostbyaddr
. getnetbyname, getnetbyaddr
. getipnodebyname, getipnodebyaddr, getnodebyname, getnodebyaddr
= host.conf has been removed from src/etc. rc.network has been modified
to warn that host.conf is no longer used at boot time. In addition, if
there is a host.conf but no nsswitch.conf, the latter is created at boot
time from the former.
Obtained from: NetBSD
2000-09-06 18:16:48 +00:00
|
|
|
broken-out fields from a line in
|
|
|
|
.Pa /etc/hosts ,
|
|
|
|
or database entries supplied by the
|
2002-01-14 16:59:03 +00:00
|
|
|
.Xr yp 8
|
Add nsswitch support. By creating an /etc/nsswitch.conf file, you can
configure FreeBSD so that various databases such as passwd and group can be
looked up using flat files, NIS, or Hesiod.
= Hesiod has been added to libc (see hesiod(3)).
= A library routine for parsing nsswitch.conf and invoking callback
functions as specified has been added to libc (see nsdispatch(3)).
= The following C library functions have been modified to use nsdispatch:
. getgrent, getgrnam, getgrgid
. getpwent, getpwnam, getpwuid
. getusershell
. getaddrinfo
. gethostbyname, gethostbyname2, gethostbyaddr
. getnetbyname, getnetbyaddr
. getipnodebyname, getipnodebyaddr, getnodebyname, getnodebyaddr
= host.conf has been removed from src/etc. rc.network has been modified
to warn that host.conf is no longer used at boot time. In addition, if
there is a host.conf but no nsswitch.conf, the latter is created at boot
time from the former.
Obtained from: NetBSD
2000-09-06 18:16:48 +00:00
|
|
|
system.
|
|
|
|
The order of the lookups is controlled by the
|
|
|
|
.Sq hosts
|
|
|
|
entry in
|
|
|
|
.Xr nsswitch.conf 5 .
|
1996-08-30 19:40:05 +00:00
|
|
|
.Bd -literal
|
1996-08-29 22:13:00 +00:00
|
|
|
struct hostent {
|
|
|
|
char *h_name; /* official name of host */
|
|
|
|
char **h_aliases; /* alias list */
|
|
|
|
int h_addrtype; /* host address type */
|
|
|
|
int h_length; /* length of address */
|
|
|
|
char **h_addr_list; /* list of addresses from name server */
|
|
|
|
};
|
|
|
|
#define h_addr h_addr_list[0] /* address, for backward compatibility */
|
1996-08-30 19:40:05 +00:00
|
|
|
.Ed
|
|
|
|
.Pp
|
1996-08-29 22:13:00 +00:00
|
|
|
The members of this structure are:
|
1996-08-30 19:40:05 +00:00
|
|
|
.Bl -tag -width h_addr_list
|
2001-02-10 10:51:39 +00:00
|
|
|
.It Va h_name
|
1996-08-29 22:13:00 +00:00
|
|
|
Official name of the host.
|
2001-02-10 10:51:39 +00:00
|
|
|
.It Va h_aliases
|
|
|
|
A
|
|
|
|
.Dv NULL Ns -terminated
|
|
|
|
array of alternate names for the host.
|
|
|
|
.It Va h_addrtype
|
1996-11-01 06:29:00 +00:00
|
|
|
The type of address being returned; usually
|
1996-08-30 19:40:05 +00:00
|
|
|
.Dv AF_INET .
|
2001-02-10 10:51:39 +00:00
|
|
|
.It Va h_length
|
1996-08-29 22:13:00 +00:00
|
|
|
The length, in bytes, of the address.
|
2001-02-10 10:51:39 +00:00
|
|
|
.It Va h_addr_list
|
|
|
|
A
|
|
|
|
.Dv NULL Ns -terminated
|
|
|
|
array of network addresses for the host.
|
1996-08-29 22:13:00 +00:00
|
|
|
Host addresses are returned in network byte order.
|
2001-02-10 10:51:39 +00:00
|
|
|
.It Va h_addr
|
1996-08-30 19:40:05 +00:00
|
|
|
The first address in
|
2001-02-10 10:51:39 +00:00
|
|
|
.Va h_addr_list ;
|
1996-08-30 19:40:05 +00:00
|
|
|
this is for backward compatibility.
|
1996-11-01 06:29:00 +00:00
|
|
|
.El
|
1996-08-30 19:40:05 +00:00
|
|
|
.Pp
|
1996-08-29 22:13:00 +00:00
|
|
|
When using the nameserver,
|
1996-08-30 19:40:05 +00:00
|
|
|
.Fn gethostbyname
|
1996-11-01 06:29:00 +00:00
|
|
|
and
|
1999-09-19 17:57:35 +00:00
|
|
|
.Fn gethostbyname2
|
1996-08-29 22:13:00 +00:00
|
|
|
will search for the named host in the current domain and its parents
|
|
|
|
unless the name ends in a dot.
|
1996-08-30 19:40:05 +00:00
|
|
|
If the name contains no dot, and if the environment variable
|
|
|
|
.Dq Ev HOSTALIASES
|
1996-08-29 22:13:00 +00:00
|
|
|
contains the name of an alias file, the alias file will first be searched
|
|
|
|
for an alias matching the input name.
|
|
|
|
See
|
1996-08-30 19:40:05 +00:00
|
|
|
.Xr hostname 7
|
1996-08-29 22:13:00 +00:00
|
|
|
for the domain search procedure and the alias file format.
|
1996-08-30 19:40:05 +00:00
|
|
|
.Pp
|
|
|
|
The
|
1996-11-01 06:29:00 +00:00
|
|
|
.Fn gethostbyname2
|
|
|
|
function is an evolution of
|
|
|
|
.Fn gethostbyname
|
|
|
|
which is intended to allow lookups in address families other than
|
|
|
|
.Dv AF_INET ,
|
|
|
|
for example
|
|
|
|
.Dv AF_INET6 .
|
|
|
|
.Pp
|
|
|
|
The
|
1996-08-30 19:40:05 +00:00
|
|
|
.Fn sethostent
|
|
|
|
function
|
|
|
|
may be used to request the use of a connected
|
|
|
|
.Tn TCP
|
|
|
|
socket for queries.
|
1996-08-29 22:13:00 +00:00
|
|
|
If the
|
1996-08-30 19:40:05 +00:00
|
|
|
.Fa stayopen
|
1996-08-29 22:13:00 +00:00
|
|
|
flag is non-zero,
|
1996-08-30 19:40:05 +00:00
|
|
|
this sets the option to send all queries to the name server using
|
|
|
|
.Tn TCP
|
2001-07-15 07:53:42 +00:00
|
|
|
and to retain the connection after each call to
|
1996-11-01 06:29:00 +00:00
|
|
|
.Fn gethostbyname ,
|
|
|
|
.Fn gethostbyname2
|
1996-08-29 22:13:00 +00:00
|
|
|
or
|
1996-08-30 19:40:05 +00:00
|
|
|
.Fn gethostbyaddr .
|
|
|
|
Otherwise, queries are performed using
|
|
|
|
.Tn UDP
|
|
|
|
datagrams.
|
|
|
|
.Pp
|
|
|
|
The
|
|
|
|
.Fn endhostent
|
|
|
|
function
|
|
|
|
closes the
|
|
|
|
.Tn TCP
|
|
|
|
connection.
|
1996-11-01 06:29:00 +00:00
|
|
|
.Pp
|
|
|
|
The
|
|
|
|
.Fn herror
|
|
|
|
function writes a message to the diagnostic output consisting of the
|
2002-12-19 09:40:28 +00:00
|
|
|
string argument
|
|
|
|
.Fa string ,
|
2001-02-10 10:51:39 +00:00
|
|
|
the constant string
|
|
|
|
.Qq Li ":\ " ,
|
|
|
|
and a message corresponding to the value of
|
1996-11-01 06:29:00 +00:00
|
|
|
.Va h_errno .
|
|
|
|
.Pp
|
|
|
|
The
|
|
|
|
.Fn hstrerror
|
|
|
|
function returns a string which is the message text corresponding to the
|
|
|
|
value of the
|
|
|
|
.Fa err
|
2002-12-19 09:40:28 +00:00
|
|
|
argument.
|
1996-08-30 19:40:05 +00:00
|
|
|
.Sh FILES
|
Add nsswitch support. By creating an /etc/nsswitch.conf file, you can
configure FreeBSD so that various databases such as passwd and group can be
looked up using flat files, NIS, or Hesiod.
= Hesiod has been added to libc (see hesiod(3)).
= A library routine for parsing nsswitch.conf and invoking callback
functions as specified has been added to libc (see nsdispatch(3)).
= The following C library functions have been modified to use nsdispatch:
. getgrent, getgrnam, getgrgid
. getpwent, getpwnam, getpwuid
. getusershell
. getaddrinfo
. gethostbyname, gethostbyname2, gethostbyaddr
. getnetbyname, getnetbyaddr
. getipnodebyname, getipnodebyaddr, getnodebyname, getnodebyaddr
= host.conf has been removed from src/etc. rc.network has been modified
to warn that host.conf is no longer used at boot time. In addition, if
there is a host.conf but no nsswitch.conf, the latter is created at boot
time from the former.
Obtained from: NetBSD
2000-09-06 18:16:48 +00:00
|
|
|
.Bl -tag -width /etc/nsswitch.conf -compact
|
1996-08-30 19:40:05 +00:00
|
|
|
.It Pa /etc/hosts
|
Add nsswitch support. By creating an /etc/nsswitch.conf file, you can
configure FreeBSD so that various databases such as passwd and group can be
looked up using flat files, NIS, or Hesiod.
= Hesiod has been added to libc (see hesiod(3)).
= A library routine for parsing nsswitch.conf and invoking callback
functions as specified has been added to libc (see nsdispatch(3)).
= The following C library functions have been modified to use nsdispatch:
. getgrent, getgrnam, getgrgid
. getpwent, getpwnam, getpwuid
. getusershell
. getaddrinfo
. gethostbyname, gethostbyname2, gethostbyaddr
. getnetbyname, getnetbyaddr
. getipnodebyname, getipnodebyaddr, getnodebyname, getnodebyaddr
= host.conf has been removed from src/etc. rc.network has been modified
to warn that host.conf is no longer used at boot time. In addition, if
there is a host.conf but no nsswitch.conf, the latter is created at boot
time from the former.
Obtained from: NetBSD
2000-09-06 18:16:48 +00:00
|
|
|
.It Pa /etc/nsswitch.conf
|
1996-11-01 06:29:00 +00:00
|
|
|
.It Pa /etc/resolv.conf
|
1996-08-30 19:40:05 +00:00
|
|
|
.El
|
2001-02-09 19:06:25 +00:00
|
|
|
.Sh EXAMPLES
|
|
|
|
Print out the hostname associated with a specific IP address:
|
2001-02-10 10:51:39 +00:00
|
|
|
.Bd -literal -offset indent
|
|
|
|
const char *ipstr = "127.0.0.1";
|
|
|
|
struct in_addr ip;
|
|
|
|
struct hostent *hp;
|
2001-02-09 19:06:25 +00:00
|
|
|
|
2001-02-10 10:51:39 +00:00
|
|
|
if (!inet_aton(ipstr, &ip))
|
|
|
|
errx(1, "can't parse IP address %s", ipstr);
|
2001-02-09 19:06:25 +00:00
|
|
|
|
2001-02-10 10:51:39 +00:00
|
|
|
if ((hp = gethostbyaddr((const char *)&ip,
|
|
|
|
sizeof ip, AF_INET)) == NULL)
|
|
|
|
errx(1, "no name associated with %s", ipstr);
|
2001-02-09 19:06:25 +00:00
|
|
|
|
2001-02-10 10:51:39 +00:00
|
|
|
printf("name associated with %s is %s\en", ipstr, hp->h_name);
|
|
|
|
.Ed
|
1996-08-30 19:40:05 +00:00
|
|
|
.Sh DIAGNOSTICS
|
2001-07-15 07:53:42 +00:00
|
|
|
Error return status from
|
1996-11-01 06:29:00 +00:00
|
|
|
.Fn gethostbyname ,
|
|
|
|
.Fn gethostbyname2
|
1996-08-29 22:13:00 +00:00
|
|
|
and
|
1996-08-30 19:40:05 +00:00
|
|
|
.Fn gethostbyaddr
|
2001-02-10 10:51:39 +00:00
|
|
|
is indicated by return of a
|
|
|
|
.Dv NULL
|
|
|
|
pointer.
|
1996-08-29 22:13:00 +00:00
|
|
|
The external integer
|
1996-08-30 19:40:05 +00:00
|
|
|
.Va h_errno
|
1996-08-29 22:13:00 +00:00
|
|
|
may then be checked to see whether this is a temporary failure
|
|
|
|
or an invalid or unknown host.
|
|
|
|
The routine
|
1996-08-30 19:40:05 +00:00
|
|
|
.Fn herror
|
1996-08-29 22:13:00 +00:00
|
|
|
can be used to print an error message describing the failure.
|
|
|
|
If its argument
|
1996-08-30 19:40:05 +00:00
|
|
|
.Fa string
|
|
|
|
is
|
2001-02-10 10:51:39 +00:00
|
|
|
.Pf non- Dv NULL ,
|
1996-08-30 19:40:05 +00:00
|
|
|
it is printed, followed by a colon and a space.
|
1996-08-29 22:13:00 +00:00
|
|
|
The error message is printed with a trailing newline.
|
1996-08-30 19:40:05 +00:00
|
|
|
.Pp
|
|
|
|
The variable
|
|
|
|
.Va h_errno
|
1996-08-29 22:13:00 +00:00
|
|
|
can have the following values:
|
1996-08-30 19:40:05 +00:00
|
|
|
.Bl -tag -width HOST_NOT_FOUND
|
|
|
|
.It Dv HOST_NOT_FOUND
|
1996-08-29 22:13:00 +00:00
|
|
|
No such host is known.
|
1996-08-30 19:40:05 +00:00
|
|
|
.It Dv TRY_AGAIN
|
1996-08-29 22:13:00 +00:00
|
|
|
This is usually a temporary error
|
|
|
|
and means that the local server did not receive
|
|
|
|
a response from an authoritative server.
|
|
|
|
A retry at some later time may succeed.
|
1996-08-30 19:40:05 +00:00
|
|
|
.It Dv NO_RECOVERY
|
1996-08-29 22:13:00 +00:00
|
|
|
Some unexpected server failure was encountered.
|
|
|
|
This is a non-recoverable error.
|
1996-08-30 19:40:05 +00:00
|
|
|
.It Dv NO_DATA
|
2001-07-15 07:53:42 +00:00
|
|
|
The requested name is valid but does not have an IP address;
|
|
|
|
this is not a temporary error.
|
1996-08-29 22:13:00 +00:00
|
|
|
This means that the name is known to the name server but there is no address
|
|
|
|
associated with this name.
|
|
|
|
Another type of request to the name server using this domain name
|
|
|
|
will result in an answer;
|
|
|
|
for example, a mail-forwarder may be registered for this domain.
|
1996-08-30 19:40:05 +00:00
|
|
|
.El
|
|
|
|
.Sh SEE ALSO
|
2001-04-27 18:18:12 +00:00
|
|
|
.Xr getaddrinfo 3 ,
|
2001-08-08 11:05:47 +00:00
|
|
|
.Xr getnameinfo 3 ,
|
2001-05-15 15:57:05 +00:00
|
|
|
.Xr inet_aton 3 ,
|
1996-08-30 19:40:05 +00:00
|
|
|
.Xr resolver 3 ,
|
|
|
|
.Xr hosts 5 ,
|
|
|
|
.Xr hostname 7 ,
|
|
|
|
.Xr named 8
|
|
|
|
.Sh CAVEAT
|
|
|
|
The
|
|
|
|
.Fn gethostent
|
|
|
|
function
|
1996-08-29 22:13:00 +00:00
|
|
|
is defined, and
|
1996-08-30 19:40:05 +00:00
|
|
|
.Fn sethostent
|
1996-08-29 22:13:00 +00:00
|
|
|
and
|
1996-08-30 19:40:05 +00:00
|
|
|
.Fn endhostent
|
1996-08-29 22:13:00 +00:00
|
|
|
are redefined,
|
|
|
|
when
|
1996-08-30 19:40:05 +00:00
|
|
|
.Xr libc 3
|
1996-08-29 22:13:00 +00:00
|
|
|
is built to use only the routines to lookup in
|
1996-08-30 19:40:05 +00:00
|
|
|
.Pa /etc/hosts
|
1996-08-29 22:13:00 +00:00
|
|
|
and not the name server.
|
1996-08-30 19:40:05 +00:00
|
|
|
.Pp
|
|
|
|
The
|
|
|
|
.Fn gethostent
|
|
|
|
function
|
1996-08-29 22:13:00 +00:00
|
|
|
reads the next line of
|
1996-08-30 19:40:05 +00:00
|
|
|
.Pa /etc/hosts ,
|
1996-08-29 22:13:00 +00:00
|
|
|
opening the file if necessary.
|
1996-08-30 19:40:05 +00:00
|
|
|
.Pp
|
|
|
|
The
|
|
|
|
.Fn sethostent
|
|
|
|
function
|
|
|
|
opens and/or rewinds the file
|
|
|
|
.Pa /etc/hosts .
|
|
|
|
If the
|
|
|
|
.Fa stayopen
|
1996-08-29 22:13:00 +00:00
|
|
|
argument is non-zero,
|
1996-08-30 19:40:05 +00:00
|
|
|
the file will not be closed after each call to
|
1996-11-01 06:29:00 +00:00
|
|
|
.Fn gethostbyname ,
|
|
|
|
.Fn gethostbyname2
|
1996-08-29 22:13:00 +00:00
|
|
|
or
|
1996-08-30 19:40:05 +00:00
|
|
|
.Fn gethostbyaddr .
|
|
|
|
.Pp
|
|
|
|
The
|
|
|
|
.Fn endhostent
|
|
|
|
function
|
|
|
|
closes the file.
|
|
|
|
.Sh HISTORY
|
|
|
|
The
|
|
|
|
.Fn herror
|
2001-07-15 07:53:42 +00:00
|
|
|
function appeared in
|
1996-08-30 19:40:05 +00:00
|
|
|
.Bx 4.3 .
|
|
|
|
The
|
|
|
|
.Fn endhostent ,
|
|
|
|
.Fn gethostbyaddr ,
|
|
|
|
.Fn gethostbyname ,
|
|
|
|
.Fn gethostent ,
|
|
|
|
and
|
|
|
|
.Fn sethostent
|
|
|
|
functions appeared in
|
|
|
|
.Bx 4.2 .
|
1996-11-01 06:29:00 +00:00
|
|
|
The
|
|
|
|
.Fn gethostbyname2
|
2001-02-10 10:51:39 +00:00
|
|
|
function first appeared in
|
|
|
|
.Tn BIND
|
|
|
|
version 4.9.4.
|
1996-08-30 19:40:05 +00:00
|
|
|
.Sh BUGS
|
|
|
|
These functions use static data storage;
|
|
|
|
if the data is needed for future use, it should be
|
|
|
|
copied before any subsequent calls overwrite it.
|
|
|
|
Only the Internet
|
1996-08-29 22:13:00 +00:00
|
|
|
address format is currently understood.
|
2001-05-08 11:21:15 +00:00
|
|
|
.Pp
|
2002-12-18 12:45:11 +00:00
|
|
|
The
|
2001-05-08 11:21:15 +00:00
|
|
|
.Fn gethostbyname2
|
2002-12-18 12:45:11 +00:00
|
|
|
function
|
2001-05-08 11:21:15 +00:00
|
|
|
cannot perform
|
|
|
|
.Dv AF_INET6
|
|
|
|
lookups over NIS.
|
2003-02-06 11:04:47 +00:00
|
|
|
The
|
2001-05-08 11:21:15 +00:00
|
|
|
.Xr getaddrinfo 3
|
2003-02-06 11:04:47 +00:00
|
|
|
function must be used instead.
|