151 строка
4.2 KiB
Groff
151 строка
4.2 KiB
Groff
.\" $Id$
|
|
.\"
|
|
.\" Copyright 2005 by Dominick Meglio.
|
|
.\"
|
|
.\" Permission to use, copy, modify, and distribute this
|
|
.\" software and its documentation for any purpose and without
|
|
.\" fee is hereby granted, provided that the above copyright
|
|
.\" notice appear in all copies and that both that copyright
|
|
.\" notice and this permission notice appear in supporting
|
|
.\" documentation, and that the name of M.I.T. not be used in
|
|
.\" advertising or publicity pertaining to distribution of the
|
|
.\" software without specific, written prior permission.
|
|
.\" M.I.T. makes no representations about the suitability of
|
|
.\" this software for any purpose. It is provided "as is"
|
|
.\" without express or implied warranty.
|
|
.\"
|
|
.TH ARES_GETNAMEINFO 3 "1 May 2009"
|
|
.SH NAME
|
|
ares_getnameinfo \- Address-to-nodename translation in protocol-independent manner
|
|
.SH SYNOPSIS
|
|
.nf
|
|
.B #include <ares.h>
|
|
.PP
|
|
.B typedef void (*ares_nameinfo_callback)(void *\fIarg\fP, int \fIstatus\fP,
|
|
.B int \fItimeouts\fP, char *\fInode\fP, char *\fIservice\fP)
|
|
.PP
|
|
.B void ares_getnameinfo(ares_channel \fIchannel\fP, const struct sockaddr *\fIsa\fP,
|
|
.B ares_socklen_t \fIsalen\fP, int \fIflags\fP, ares_nameinfo_callback \fIcallback\fP,
|
|
.B void *\fIarg\fP)
|
|
.fi
|
|
.SH DESCRIPTION
|
|
The
|
|
.B ares_getnameinfo
|
|
function is defined for protocol-independent address translation. The function
|
|
is a combination of \fIares_gethostbyaddr(3)\fP and \fIgetservbyport(3)\fP. The function will
|
|
translate the address either by executing a host query on the name service channel
|
|
identified by
|
|
.IR channel
|
|
or it will attempt to resolve it locally if possible.
|
|
The parameters
|
|
.I sa
|
|
and
|
|
.I len
|
|
give the address as a sockaddr structure, and
|
|
.I flags
|
|
gives the options that the function will use. Valid flags are listed below:
|
|
.TP 19
|
|
.B ARES_NI_NOFQDN
|
|
Only the nodename portion of the FQDN is returned for local hosts.
|
|
.TP 19
|
|
.B ARES_NI_NUMERICHOST
|
|
The numeric form of the hostname is returned rather than the name.
|
|
.TP 19
|
|
.B ARES_NI_NAMEREQD
|
|
An error is returned if the hostname cannot be found in the DNS.
|
|
.TP 19
|
|
.B ARES_NI_NUMERICSERV
|
|
The numeric form of the service is returned rather than the name.
|
|
.TP 19
|
|
.B ARES_NI_TCP
|
|
The service name is to be looked up for the TCP protocol.
|
|
.TP 19
|
|
.B ARES_NI_UDP
|
|
The service name is to be looked up for the UDP protocol.
|
|
.TP 19
|
|
.B ARES_NI_SCTP
|
|
The service name is to be looked up for the SCTP protocol.
|
|
.TP 19
|
|
.B ARES_NI_DCCP
|
|
The service name is to be looked up for the DCCP protocol.
|
|
.TP 19
|
|
.B ARES_NI_NUMERICSCOPE
|
|
The numeric form of the scope ID is returned rather than the name.
|
|
.TP 19
|
|
.B ARES_NI_LOOKUPHOST
|
|
A hostname lookup is being requested.
|
|
.TP 19
|
|
.B ARES_NI_LOOKUPSERVICE
|
|
A service name lookup is being requested.
|
|
.PP
|
|
When the query
|
|
is complete or has
|
|
failed, the ares library will invoke \fIcallback\fP. Completion or failure of
|
|
the query may happen immediately, or may happen during a later call to
|
|
\fIares_process(3)\fP, \fIares_destroy(3)\fP or \fIares_cancel(3)\fP.
|
|
.PP
|
|
The callback argument
|
|
.I arg
|
|
is copied from the
|
|
.B ares_getnameinfo
|
|
argument
|
|
.IR arg .
|
|
The callback argument
|
|
.I status
|
|
indicates whether the query succeeded and, if not, how it failed. It
|
|
may have any of the following values:
|
|
.TP 19
|
|
.B ARES_SUCCESS
|
|
The host lookup completed successfully.
|
|
.TP 19
|
|
.B ARES_ENOTIMP
|
|
The ares library does not know how to look up addresses of type
|
|
.IR family .
|
|
.TP 19
|
|
.B ARES_ENOTFOUND
|
|
The address
|
|
.I addr
|
|
was not found.
|
|
.TP 19
|
|
.B ARES_ENOMEM
|
|
Memory was exhausted.
|
|
.TP 19
|
|
.B ARES_EDESTRUCTION
|
|
The name service channel
|
|
.I channel
|
|
is being destroyed; the query will not be completed.
|
|
.TP 19
|
|
.B ARES_EBADFLAGS
|
|
The
|
|
.I flags
|
|
parameter contains an illegal value.
|
|
.PP
|
|
The callback argument
|
|
.I timeouts
|
|
reports how many times a query timed out during the execution of the
|
|
given request.
|
|
.PP
|
|
On successful completion of the query, the callback argument
|
|
.I node
|
|
contains a string representing the hostname (assuming
|
|
.B ARES_NI_LOOKUPHOST
|
|
was specified). Additionally,
|
|
.I service
|
|
contains a string representing the service name (assuming
|
|
.B ARES_NI_LOOKUPSERVICE
|
|
was specified).
|
|
If the query did not complete successfully, or one of the values
|
|
was not requested,
|
|
.I node
|
|
or
|
|
.I service
|
|
will be
|
|
.BR NULL .
|
|
.SH SEE ALSO
|
|
.BR ares_process (3),
|
|
.BR ares_getaddrinfo (3)
|
|
.SH AUTHOR
|
|
Dominick Meglio
|
|
.br
|
|
Copyright 2005 by Dominick Meglio.
|