GETNAMEINFO(3) FreeBSD Library Functions Manual GETNAMEINFO(3) NNAAMMEE ggeettnnaammeeiinnffoo -- address-to-name translation in protocol-independent manner SSYYNNOOPPSSIISS ##iinncclluuddee <> ##iinncclluuddee <> _i_n_t ggeettnnaammeeiinnffoo(_c_o_n_s_t _s_t_r_u_c_t _s_o_c_k_a_d_d_r _*_s_a, _s_o_c_k_l_e_n___t _s_a_l_e_n, _c_h_a_r _*_h_o_s_t, _s_i_z_e___t _h_o_s_t_l_e_n, _c_h_a_r _*_s_e_r_v, _s_i_z_e___t _s_e_r_v_l_e_n, _i_n_t _f_l_a_g_s); DDEESSCCRRIIPPTTIIOONN The ggeettnnaammeeiinnffoo() function is defined for protocol-independent address- to-nodename translation. It performs functionality of gethostbyaddr(3) and getservbyport(3) in more sophisticated manner. The _s_a arguement is a pointer to a generic socket address structure of size _s_a_l_e_n. The arguements _h_o_s_t and _s_e_r_v are pointers to buffers to hold the return values. Their sizes are specified by _h_o_s_t_l_e_n and _s_e_r_v_l_e_n repectively. Either _h_o_s_t or _s_e_r_v may be NULL if the hostname or service name is not required. The _f_l_a_g_s arguement modifies the behaviour of ggeettnnaammeeiinnffoo() as follows: If NI_NOFQDN is set only the unqualified hostname is returned for local fully qualified names. If NI_NUMERICHOST is set then the numeric form of the hostname is returned. If NI_NAMEREQD is set, then a error is returned if the hostname cannot be looked up. If NI_NUMERICSERV is set then the service is returned in numeric form. If NI_DGRAM is set then the service is UDP based rather than TCP based. SSEEEE AALLSSOO getaddrinfo(3), gethostbyaddr(3), getservbyport(3), hosts(5), services(5), hostname(7), R. Gilligan, S. Thomson, J. Bound, and W. Stevens, ``Basic Socket Inter- face Extensions for IPv6,'' RFC2133, April 1997. SSTTAANNDDAARRDDSS The ggeettaaddddrriinnffoo() function is defined IEEE POSIX 1003.1g draft specifica- tion, and documented in ``Basic Socket Interface Extensions for IPv6'' (RFC2133). January 11, 1999