1LWRES_GETNAMEINFO(3)                 BIND9                LWRES_GETNAMEINFO(3)
2
3
4

NAME

6       lwres_getnameinfo - lightweight resolver socket address structure to
7       hostname and service name
8

SYNOPSIS

10       #include <lwres/netdb.h>
11
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);
15

DESCRIPTION

17       This function is equivalent to the getnameinfo(3) function defined in
18       RFC2133.  lwres_getnameinfo() returns the hostname for the struct
19       sockaddrsa which is salen bytes long. The hostname is of length hostlen
20       and is returned via *host.  The maximum length of the hostname is 1025
21       bytes: NI_MAXHOST.
22
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.
26
27       The flags argument sets the following bits:
28
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.
32
33       NI_NUMERICHOST
34           Return the address in numeric form, as if calling inet_ntop(),
35           instead of a host name.
36
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.
42
43       NI_NUMERICSERV
44           The service name is returned as a digit string representing the
45           port number.
46
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.
52

RETURN VALUES

54       lwres_getnameinfo() returns 0 on success or a non-zero error code if an
55       error occurs.
56

SEE ALSO

58       RFC2133(), getservbyport(3), lwres(3), lwres_getnameinfo(3),
59       lwres_getnamebyaddr(3).  lwres_net_ntop(3).
60

BUGS

62       RFC2133 fails to define what the nonzero return values of
63       getnameinfo(3) are.
64

AUTHOR

66       Internet Systems Consortium, Inc.
67

69       Copyright © 2000, 2001, 2004, 2005, 2007, 2014-2016, 2018 Internet
70       Systems Consortium, Inc. ("ISC")
71
72
73
74ISC                               2007-06-18              LWRES_GETNAMEINFO(3)
Impressum