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diff --git a/contrib/bind9/lib/lwres/man/lwres_gethostent.3 b/contrib/bind9/lib/lwres/man/lwres_gethostent.3 new file mode 100644 index 0000000..3706727 --- /dev/null +++ b/contrib/bind9/lib/lwres/man/lwres_gethostent.3 @@ -0,0 +1,315 @@ +.\" Copyright (C) 2004, 2005, 2007 Internet Systems Consortium, Inc. ("ISC") +.\" Copyright (C) 2001 Internet Software Consortium. +.\" +.\" Permission to use, copy, modify, and/or 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. +.\" +.\" $Id$ +.\" +.hy 0 +.ad l +.\" Title: lwres_gethostent +.\" Author: +.\" Generator: DocBook XSL Stylesheets v1.71.1 <http://docbook.sf.net/> +.\" Date: Jun 30, 2000 +.\" Manual: BIND9 +.\" Source: BIND9 +.\" +.TH "LWRES_GETHOSTENT" "3" "Jun 30, 2000" "BIND9" "BIND9" +.\" disable hyphenation +.nh +.\" disable justification (adjust text to left margin only) +.ad l +.SH "NAME" +lwres_gethostbyname, lwres_gethostbyname2, lwres_gethostbyaddr, lwres_gethostent, lwres_sethostent, lwres_endhostent, lwres_gethostbyname_r, lwres_gethostbyaddr_r, lwres_gethostent_r, lwres_sethostent_r, lwres_endhostent_r \- lightweight resolver get network host entry +.SH "SYNOPSIS" +.nf +#include <lwres/netdb.h> +.fi +.HP 37 +.BI "struct hostent * lwres_gethostbyname(const\ char\ *" "name" ");" +.HP 38 +.BI "struct hostent * lwres_gethostbyname2(const\ char\ *" "name" ", int\ " "af" ");" +.HP 37 +.BI "struct hostent * lwres_gethostbyaddr(const\ char\ *" "addr" ", int\ " "len" ", int\ " "type" ");" +.HP 34 +.BI "struct hostent * lwres_gethostent(void);" +.HP 22 +.BI "void lwres_sethostent(int\ " "stayopen" ");" +.HP 22 +.BI "void lwres_endhostent(void);" +.HP 39 +.BI "struct hostent * lwres_gethostbyname_r(const\ char\ *" "name" ", struct\ hostent\ *" "resbuf" ", char\ *" "buf" ", int\ " "buflen" ", int\ *" "error" ");" +.HP 39 +.BI "struct hostent * lwres_gethostbyaddr_r(const\ char\ *" "addr" ", int\ " "len" ", int\ " "type" ", struct\ hostent\ *" "resbuf" ", char\ *" "buf" ", int\ " "buflen" ", int\ *" "error" ");" +.HP 36 +.BI "struct hostent * lwres_gethostent_r(struct\ hostent\ *" "resbuf" ", char\ *" "buf" ", int\ " "buflen" ", int\ *" "error" ");" +.HP 24 +.BI "void lwres_sethostent_r(int\ " "stayopen" ");" +.HP 24 +.BI "void lwres_endhostent_r(void);" +.SH "DESCRIPTION" +.PP +These functions provide hostname\-to\-address and address\-to\-hostname lookups by means of the lightweight resolver. They are similar to the standard +\fBgethostent\fR(3) +functions provided by most operating systems. They use a +\fBstruct hostent\fR +which is usually defined in +\fI<namedb.h>\fR. +.PP +.RS 4 +.nf +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 */ +.fi +.RE +.sp +.PP +The members of this structure are: +.PP +\fBh_name\fR +.RS 4 +The official (canonical) name of the host. +.RE +.PP +\fBh_aliases\fR +.RS 4 +A NULL\-terminated array of alternate names (nicknames) for the host. +.RE +.PP +\fBh_addrtype\fR +.RS 4 +The type of address being returned \(em +\fBPF_INET\fR +or +\fBPF_INET6\fR. +.RE +.PP +\fBh_length\fR +.RS 4 +The length of the address in bytes. +.RE +.PP +\fBh_addr_list\fR +.RS 4 +A +\fBNULL\fR +terminated array of network addresses for the host. Host addresses are returned in network byte order. +.RE +.PP +For backward compatibility with very old software, +\fBh_addr\fR +is the first address in +\fBh_addr_list.\fR +.PP +\fBlwres_gethostent()\fR, +\fBlwres_sethostent()\fR, +\fBlwres_endhostent()\fR, +\fBlwres_gethostent_r()\fR, +\fBlwres_sethostent_r()\fR +and +\fBlwres_endhostent_r()\fR +provide iteration over the known host entries on systems that provide such functionality through facilities like +\fI/etc/hosts\fR +or NIS. The lightweight resolver does not currently implement these functions; it only provides them as stub functions that always return failure. +.PP +\fBlwres_gethostbyname()\fR +and +\fBlwres_gethostbyname2()\fR +look up the hostname +\fIname\fR. +\fBlwres_gethostbyname()\fR +always looks for an IPv4 address while +\fBlwres_gethostbyname2()\fR +looks for an address of protocol family +\fIaf\fR: either +\fBPF_INET\fR +or +\fBPF_INET6\fR +\(em IPv4 or IPV6 addresses respectively. Successful calls of the functions return a +\fBstruct hostent\fRfor the name that was looked up. +\fBNULL\fR +is returned if the lookups by +\fBlwres_gethostbyname()\fR +or +\fBlwres_gethostbyname2()\fR +fail. +.PP +Reverse lookups of addresses are performed by +\fBlwres_gethostbyaddr()\fR. +\fIaddr\fR +is an address of length +\fIlen\fR +bytes and protocol family +\fItype\fR +\(em +\fBPF_INET\fR +or +\fBPF_INET6\fR. +\fBlwres_gethostbyname_r()\fR +is a thread\-safe function for forward lookups. If an error occurs, an error code is returned in +\fI*error\fR. +\fIresbuf\fR +is a pointer to a +\fBstruct hostent\fR +which is initialised by a successful call to +\fBlwres_gethostbyname_r()\fR. +\fIbuf\fR +is a buffer of length +\fIlen\fR +bytes which is used to store the +\fBh_name\fR, +\fBh_aliases\fR, and +\fBh_addr_list\fR +elements of the +\fBstruct hostent\fR +returned in +\fIresbuf\fR. Successful calls to +\fBlwres_gethostbyname_r()\fR +return +\fIresbuf\fR, which is a pointer to the +\fBstruct hostent\fR +it created. +.PP +\fBlwres_gethostbyaddr_r()\fR +is a thread\-safe function that performs a reverse lookup of address +\fIaddr\fR +which is +\fIlen\fR +bytes long and is of protocol family +\fItype\fR +\(em +\fBPF_INET\fR +or +\fBPF_INET6\fR. If an error occurs, the error code is returned in +\fI*error\fR. The other function parameters are identical to those in +\fBlwres_gethostbyname_r()\fR. +\fIresbuf\fR +is a pointer to a +\fBstruct hostent\fR +which is initialised by a successful call to +\fBlwres_gethostbyaddr_r()\fR. +\fIbuf\fR +is a buffer of length +\fIlen\fR +bytes which is used to store the +\fBh_name\fR, +\fBh_aliases\fR, and +\fBh_addr_list\fR +elements of the +\fBstruct hostent\fR +returned in +\fIresbuf\fR. Successful calls to +\fBlwres_gethostbyaddr_r()\fR +return +\fIresbuf\fR, which is a pointer to the +\fBstruct hostent()\fR +it created. +.SH "RETURN VALUES" +.PP +The functions +\fBlwres_gethostbyname()\fR, +\fBlwres_gethostbyname2()\fR, +\fBlwres_gethostbyaddr()\fR, and +\fBlwres_gethostent()\fR +return NULL to indicate an error. In this case the global variable +\fBlwres_h_errno\fR +will contain one of the following error codes defined in +\fI<lwres/netdb.h>\fR: +.PP +\fBHOST_NOT_FOUND\fR +.RS 4 +The host or address was not found. +.RE +.PP +\fBTRY_AGAIN\fR +.RS 4 +A recoverable error occurred, e.g., a timeout. Retrying the lookup may succeed. +.RE +.PP +\fBNO_RECOVERY\fR +.RS 4 +A non\-recoverable error occurred. +.RE +.PP +\fBNO_DATA\fR +.RS 4 +The name exists, but has no address information associated with it (or vice versa in the case of a reverse lookup). The code NO_ADDRESS is accepted as a synonym for NO_DATA for backwards compatibility. +.RE +.PP +\fBlwres_hstrerror\fR(3) +translates these error codes to suitable error messages. +.PP +\fBlwres_gethostent()\fR +and +\fBlwres_gethostent_r()\fR +always return +\fBNULL\fR. +.PP +Successful calls to +\fBlwres_gethostbyname_r()\fR +and +\fBlwres_gethostbyaddr_r()\fR +return +\fIresbuf\fR, a pointer to the +\fBstruct hostent\fR +that was initialised by these functions. They return +\fBNULL\fR +if the lookups fail or if +\fIbuf\fR +was too small to hold the list of addresses and names referenced by the +\fBh_name\fR, +\fBh_aliases\fR, and +\fBh_addr_list\fR +elements of the +\fBstruct hostent\fR. If +\fIbuf\fR +was too small, both +\fBlwres_gethostbyname_r()\fR +and +\fBlwres_gethostbyaddr_r()\fR +set the global variable +\fBerrno\fR +to +\fBERANGE\fR. +.SH "SEE ALSO" +.PP +\fBgethostent\fR(3), +\fBlwres_getipnode\fR(3), +\fBlwres_hstrerror\fR(3) +.SH "BUGS" +.PP +\fBlwres_gethostbyname()\fR, +\fBlwres_gethostbyname2()\fR, +\fBlwres_gethostbyaddr()\fR +and +\fBlwres_endhostent()\fR +are not thread safe; they return pointers to static data and provide error codes through a global variable. Thread\-safe versions for name and address lookup are provided by +\fBlwres_gethostbyname_r()\fR, and +\fBlwres_gethostbyaddr_r()\fR +respectively. +.PP +The resolver daemon does not currently support any non\-DNS name services such as +\fI/etc/hosts\fR +or +\fBNIS\fR, consequently the above functions don't, either. +.SH "COPYRIGHT" +Copyright \(co 2004, 2005, 2007 Internet Systems Consortium, Inc. ("ISC") +.br +Copyright \(co 2001 Internet Software Consortium. +.br |
