1b5677b36SchristosHESIOD(3) HESIOD(3) 2b5677b36Schristos 3b5677b36Schristos 4b5677b36Schristos 5b5677b36SchristosNNAAMMEE 6b5677b36Schristos hesiod, hesiod_init, hesiod_resolve, hesiod_free_list, hesiod_to_bind, 7b5677b36Schristos hesiod_end - Hesiod name server interface library 8b5677b36Schristos 9b5677b36SchristosSSYYNNOOPPSSIISS 10b5677b36Schristos ##iinncclluuddee <<hheessiioodd..hh>> 11b5677b36Schristos 12b5677b36Schristos iinntt hheessiioodd__iinniitt((vvooiidd ****_c_o_n_t_e_x_t)) 13b5677b36Schristos cchhaarr ****hheessiioodd__rreessoollvvee((vvooiidd **_c_o_n_t_e_x_t,, ccoonnsstt cchhaarr **_n_a_m_e,, 14b5677b36Schristos ccoonnsstt cchhaarr **_t_y_p_e)) 15b5677b36Schristos vvooiidd hheessiioodd__ffrreeee__lliisstt((vvooiidd **_c_o_n_t_e_x_t,, cchhaarr ****_l_i_s_t));; 16b5677b36Schristos cchhaarr **hheessiioodd__ttoo__bbiinndd((vvooiidd **_c_o_n_t_e_x_t,, ccoonnsstt cchhaarr **_n_a_m_e,, 17b5677b36Schristos ccoonnsstt cchhaarr **_t_y_p_e)) 18b5677b36Schristos vvooiidd hheessiioodd__eenndd((vvooiidd **_c_o_n_t_e_x_t)) 19b5677b36Schristos 20b5677b36SchristosDDEESSCCRRIIPPTTIIOONN 21*5bbd2a12Schristos This family of functions allows you to perform lookups of Hesiod infor- 22b5677b36Schristos mation, which is stored as text records in the Domain Name Service. To 23b5677b36Schristos perform lookups, you must first initialize a _c_o_n_t_e_x_t, an opaque object 24b5677b36Schristos which stores information used internally by the library between calls. 25b5677b36Schristos _h_e_s_i_o_d___i_n_i_t initializes a context, storing a pointer to the context in 26b5677b36Schristos the location pointed to by the _c_o_n_t_e_x_t argument. _h_e_s_i_o_d___e_n_d frees the 27b5677b36Schristos resources used by a context. 28b5677b36Schristos 29b5677b36Schristos _h_e_s_i_o_d___r_e_s_o_l_v_e is the primary interface to the library. If successful, 30b5677b36Schristos it returns a list of one or more strings giving the records matching 31b5677b36Schristos _n_a_m_e and _t_y_p_e. The last element of the list is followed by a NULL 32*5bbd2a12Schristos pointer. It is the caller's responsibility to call _h_e_s_i_o_d___f_r_e_e___l_i_s_t to 33b5677b36Schristos free the resources used by the returned list. 34b5677b36Schristos 35*5bbd2a12Schristos _h_e_s_i_o_d___t_o___b_i_n_d converts _n_a_m_e and _t_y_p_e into the DNS name used by _h_e_s_- 36*5bbd2a12Schristos _i_o_d___r_e_s_o_l_v_e. It is the caller's responsibility to free the returned 37b5677b36Schristos string using _f_r_e_e. 38b5677b36Schristos 39b5677b36SchristosRREETTUURRNN VVAALLUUEESS 40b5677b36Schristos If successful, _h_e_s_i_o_d___i_n_i_t returns 0; otherwise it returns -1 and sets 41*5bbd2a12Schristos _e_r_r_n_o to indicate the error. On failure, _h_e_s_i_o_d___r_e_s_o_l_v_e and _h_e_s_- 42b5677b36Schristos _i_o_d___t_o___b_i_n_d return NULL and set the global variable _e_r_r_n_o to indicate 43b5677b36Schristos the error. 44b5677b36Schristos 45b5677b36SchristosEENNVVIIRROONNMMEENNTT 46b5677b36Schristos If the environment variable HHEESS__DDOOMMAAIINN is set, it will override the 47b5677b36Schristos domain in the Hesiod configuration file. If the environment variable 48*5bbd2a12Schristos HHEESSIIOODD__CCOONNFFIIGG is set, it specifies the location of the Hesiod configu- 49b5677b36Schristos ration file. 50b5677b36Schristos 51b5677b36SchristosSSEEEE AALLSSOO 52*5bbd2a12Schristos `Hesiod - Project Athena Technical Plan -- Name Service' 53b5677b36Schristos 54b5677b36SchristosEERRRROORRSS 55b5677b36Schristos Hesiod calls may fail because of: 56b5677b36Schristos 57b5677b36Schristos ENOMEM Insufficient memory was available to carry out the requested 58b5677b36Schristos operation. 59b5677b36Schristos 60b5677b36Schristos ENOEXEC 61b5677b36Schristos _h_e_s_i_o_d___i_n_i_t failed because the Hesiod configuration file was 62b5677b36Schristos invalid. 63b5677b36Schristos 64b5677b36Schristos ECONNREFUSED 65b5677b36Schristos _h_e_s_i_o_d___r_e_s_o_l_v_e failed because no name server could be contacted 66b5677b36Schristos to answer the query. 67b5677b36Schristos 68b5677b36Schristos EMSGSIZE 69b5677b36Schristos _h_e_s_i_o_d___r_e_s_o_l_v_e failed because the query or response was too big 70b5677b36Schristos to fit into the packet buffers. 71b5677b36Schristos 72b5677b36Schristos ENOENT _h_e_s_i_o_d___r_e_s_o_l_v_e failed because the name server had no text 73b5677b36Schristos records matching _n_a_m_e and _t_y_p_e, or _h_e_s_i_o_d___t_o___b_i_n_d failed because 74b5677b36Schristos the _n_a_m_e argument had a domain extension which could not be 75*5bbd2a12Schristos resolved with type ``rhs-extension'' in the local Hesiod domain. 76b5677b36Schristos 77b5677b36SchristosAAUUTTHHOORR 78b5677b36Schristos Steve Dyer, IBM/Project Athena 79b5677b36Schristos Greg Hudson, MIT Team Athena 80b5677b36Schristos Copyright 1987, 1988, 1995, 1996 by the Massachusetts Institute of 81b5677b36Schristos Technology. 82b5677b36Schristos 83b5677b36SchristosBBUUGGSS 84*5bbd2a12Schristos The strings corresponding to the _e_r_r_n_o values set by the Hesiod func- 85b5677b36Schristos tions are not particularly indicative of what went wrong, especially 86b5677b36Schristos for _E_N_O_E_X_E_C and _E_N_O_E_N_T. 87b5677b36Schristos 88b5677b36Schristos 89b5677b36Schristos 90b5677b36Schristos 30 November 1996 HESIOD(3) 91