GETNETENT(3) 1990 GETNETENT(3) NNAAMMEE getnetent, getnetbyaddr, getnetbyname, setnetent, endnetent - get network entry SSYYNNOOPPSSIISS ##iinncclluuddee <<nneettddbb..hh>> ssttrruucctt nneetteenntt **ggeettnneetteenntt(()) ssttrruucctt nneetteenntt **ggeettnneettbbyynnaammee((nnaammee)) cchhaarr **nnaammee;; ssttrruucctt nneetteenntt **ggeettnneettbbyyaaddddrr((nneett,, ttyyppee)) lloonngg nneett;; iinntt ttyyppee;; sseettnneetteenntt((ssttaayyooppeenn)) iinntt ssttaayyooppeenn;; eennddnneetteenntt(()) DDEESSCCRRIIPPTTIIOONN _G_e_t_n_e_t_e_n_t, _g_e_t_n_e_t_b_y_n_a_m_e, and _g_e_t_n_e_t_b_y_a_d_d_r each return a pointer to an object with the following structure containing the broken-out fields of a line in the network data base, /_e_t_c/_n_e_t_w_o_r_k_s. struct netent { char *n_name; /* official name of net */ char **n_aliases; /* alias list */ int n_addrtype; /* net number type */ unsigned long n_net; /* net number */ }; The members of this structure are: n_name The official name of the network. n_aliases A zero terminated list of alternate names for the network. n_addrtype The type of the network number returned; currently only AF_INET. n_net The network number. Network numbers are returned in machine byte order. _G_e_t_n_e_t_e_n_t reads the next line of the file, opening the file if necessary. _S_e_t_n_e_t_e_n_t opens and rewinds the file. If the _s_t_a_y_o_p_e_n flag is non-zero, the net data base will not be closed after each Printed 7/27/90 June 1 GETNETENT(3) 1990 GETNETENT(3) call to _g_e_t_n_e_t_b_y_n_a_m_e or _g_e_t_n_e_t_b_y_a_d_d_r. _E_n_d_n_e_t_e_n_t closes the file. _G_e_t_n_e_t_b_y_n_a_m_e and _g_e_t_n_e_t_b_y_a_d_d_r sequentially search from the beginning of the file until a matching net name or net address and type is found, or until EOF is encountered. Network numbers are supplied in host order. FFIILLEESS /etc/networks SSEEEE AALLSSOO networks(5) DDIIAAGGNNOOSSTTIICCSS Null pointer (0) returned on EOF or error. BBUUGGSS All information is contained in a static area so it must be copied if it is to be saved. Only Internet network numbers are currently understood. Expecting network numbers to fit in no more than 32 bits is probably naive. Printed 7/27/90 June 2