lwres_getnameinfo — lightweight resolver socket address structure to hostname and service name
#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 ); | 
       This function is equivalent to the
      getnameinfo(3) function defined in RFC2133.
      lwres_getnameinfo() returns the
      hostname 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_NOFQDNA fully qualified domain name is not required for local hosts. The local part of the fully qualified domain name is returned instead.
NI_NUMERICHOSTReturn the address in numeric form, as if calling inet_ntop(), instead of a host name.
NI_NAMEREQDA 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_NUMERICSERVThe service name is returned as a digit string representing the port number.
NI_DGRAMSpecifies 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.