LWRES_GETNAMEINFO(3)LWRES_GETNAMEINFO(3)NAMElwres_getnameinfo - lightweight resolver socket address
structure to hostname and service name
SYNOPSIS
#include <lwres/netdb.h>
int lwres_getnameinfo(const struct sockaddr *sa, size_t
salen, char *host, size_t hostlen, char *serv, size_t
servlen, int flags);
DESCRIPTION
This function is equivalent to the getnameinfo(3) function
defined in RFC2133. lwres_getnameinfo() returns the host-
name for the struct sockaddr sa which is salen bytes long.
The hostname is of length hostlen and is returned via
*host. The maximum length of the hostname is 1025 bytes:
NI_MAXHOST.
The name of the service associated with the port number in
sa is returned in *serv. It is servlen bytes long. The
maximum length of the service name is NI_MAXSERV - 32
bytes.
The flags argument sets the following bits:
NI_NOFQDN
A fully qualified domain name is not required for
local hosts. The local part of the fully qualified
domain name is returned instead.
NI_NUMERICHOST
Return the address in numeric form, as if calling
inet_ntop(), instead of a host name.
NI_NAMEREQD
A name is required. If the hostname cannot be found
in the DNS and this flag is set, a non-zero error
code is returned. If the hostname is not found and
the flag is not set, the address is returned in
numeric form.
NI_NUMERICSERV
The service name is returned as a digit string rep-
resenting the port number.
NI_DGRAM
Specifies that the service being looked up is a
datagram service, and causes getservbyport() to be
called with a second argument of "udp" instead of
its default of "tcp". This is required for the few
ports (512-514) that have different services for
UDP and TCP.
RETURN VALUESlwres_getnameinfo() returns 0 on success or a non-zero
error code if an error occurs.
SEE ALSO
RFC2133, getservbyport(3), lwres(3), lwres_getnameinfo(3),
lwres_getnamebyaddr(3). lwres_net_ntop(3).
BUGS
RFC2133 fails to define what the nonzero return values of
getnameinfo(3) are.
BIND9 Jun 30, 2000 LWRES_GETNAMEINFO(3)
