Finding an address that can be used to connect to a remote machine is done with either of the following commands:

#include <netdb.h>

struct hostent *gethostbyname(char *name)

struct hostent *gethostbyaddr(char *addr,

int len, int type)

name contains the host name for which the IP address is needed. addr points to a structure of type in_addr and len is the size in bytes of this structure. In this discussion type is always AF_INET since the discussion is limited to use of IP addresses on the Internet.

Both calls return a pointer to a host entry structure.

This structure has the following form:

struct hostent {

char *h_name; /*official name of host*/

char **h_aliases; /* alias list */

int h_addrtype; /* address type */

int h_length; /* length of address */

char **h_addr_list;

/* list of addresses from name server */

#define h_addr h_addr_list[0]

/* address for backward compatibility */

};