1LWRES_GETNAMEINFO(3)                 BIND9                LWRES_GETNAMEINFO(3)
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NAME

6       lwres_getnameinfo - lightweight resolver socket address structure to
7       hostname and service name
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SYNOPSIS

10       #include <lwres/netdb.h>
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12       int lwres_getnameinfo(const struct sockaddr *sa, size_t salen,
13                             char *host, size_t hostlen, char *serv,
14                             size_t servlen, int flags);
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DESCRIPTION

17       This function is equivalent to the getnameinfo(3) function defined in
18       RFC2133.  lwres_getnameinfo() returns the hostname for the struct
19       sockaddr sa which is salen bytes long. The hostname is of length
20       hostlen and is returned via *host.  The maximum length of the hostname
21       is 1025 bytes: NI_MAXHOST.
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23       The name of the service associated with the port number in sa is
24       returned in *serv.  It is servlen bytes long. The maximum length of the
25       service name is NI_MAXSERV - 32 bytes.
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27       The flags argument sets the following bits:
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29       NI_NOFQDN
30           A fully qualified domain name is not required for local hosts. The
31           local part of the fully qualified domain name is returned instead.
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33       NI_NUMERICHOST
34           Return the address in numeric form, as if calling inet_ntop(),
35           instead of a host name.
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37       NI_NAMEREQD
38           A name is required. If the hostname cannot be found in the DNS and
39           this flag is set, a non-zero error code is returned. If the
40           hostname is not found and the flag is not set, the address is
41           returned in numeric form.
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43       NI_NUMERICSERV
44           The service name is returned as a digit string representing the
45           port number.
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47       NI_DGRAM
48           Specifies that the service being looked up is a datagram service,
49           and causes getservbyport() to be called with a second argument of
50           "udp" instead of its default of "tcp". This is required for the few
51           ports (512-514) that have different services for UDP and TCP.
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RETURN VALUES

54       lwres_getnameinfo() returns 0 on success or a non-zero error code if an
55       error occurs.
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SEE ALSO

58       RFC2133(), getservbyport(3), lwres(3), lwres_getnameinfo(3),
59       lwres_getnamebyaddr(3).  lwres_net_ntop(3).
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BUGS

62       RFC2133 fails to define what the nonzero return values of
63       getnameinfo(3) are.
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AUTHOR

66       Internet Systems Consortium, Inc.
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69       Copyright © 2000, 2001, 2004, 2005, 2007, 2014-2016, 2018-2021 Internet
70       Systems Consortium, Inc. ("ISC")
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74ISC                               2007-06-18              LWRES_GETNAMEINFO(3)
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