HESIOD(3) HESIOD(3)
NNAAMMEE
hesiod, hesiod_init, hesiod_resolve, hesiod_free_list,
hesiod_to_bind, hesiod_end - Hesiod name server interface
library
SSYYNNOOPPSSIISS
##iinncclluuddee <<hheessiioodd..hh>>
iinntt hheessiioodd__iinniitt((vvooiidd ****_c_o_n_t_e_x_t))
cchhaarr ****hheessiioodd__rreessoollvvee((vvooiidd **_c_o_n_t_e_x_t,, ccoonnsstt cchhaarr **_n_a_m_e,,
ccoonnsstt cchhaarr **_t_y_p_e))
vvooiidd hheessiioodd__ffrreeee__lliisstt((vvooiidd **_c_o_n_t_e_x_t,, cchhaarr ****_l_i_s_t));;
cchhaarr **hheessiioodd__ttoo__bbiinndd((vvooiidd **_c_o_n_t_e_x_t,, ccoonnsstt cchhaarr **_n_a_m_e,,
ccoonnsstt cchhaarr **_t_y_p_e))
vvooiidd hheessiioodd__eenndd((vvooiidd **_c_o_n_t_e_x_t))
DDEESSCCRRIIPPTTIIOONN
This family of functions allows you to perform lookups of
Hesiod information, which is stored as text records in the
Domain Name Service. To perform lookups, you must first
initialize a _c_o_n_t_e_x_t, an opaque object which stores infor-
mation used internally by the library between calls. _h_e_s_-
_i_o_d___i_n_i_t initializes a context, storing a pointer to the
context in the location pointed to by the _c_o_n_t_e_x_t argu-
ment. _h_e_s_i_o_d___e_n_d frees the resources used by a context.
_h_e_s_i_o_d___r_e_s_o_l_v_e is the primary interface to the library.
If successful, it returns a list of one or more strings
giving the records matching _n_a_m_e and _t_y_p_e. The last ele-
ment of the list is followed by a NULL pointer. It is the
caller's responsibility to call _h_e_s_i_o_d___f_r_e_e___l_i_s_t to free
the resources used by the returned list.
_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_i_o_d___r_e_s_o_l_v_e. It is the caller's responsibility
to free the returned string using _f_r_e_e.
RREETTUURRNN VVAALLUUEESS
If successful, _h_e_s_i_o_d___i_n_i_t returns 0; otherwise it returns
-1 and sets _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_i_o_d___t_o___b_i_n_d return NULL and set the
global variable _e_r_r_n_o to indicate the error.
EENNVVIIRROONNMMEENNTT
If the environment variable HHEESS__DDOOMMAAIINN is set, it will
override the domain in the Hesiod configuration file. If
the environment variable HHEESSIIOODD__CCOONNFFIIGG is set, it speci-
fies the location of the Hesiod configuration file.
SSEEEE AALLSSOO
`Hesiod - Project Athena Technical Plan -- Name Service',
named(8), hesiod.conf(5)
30 November 1996 1
HESIOD(3) HESIOD(3)
EERRRROORRSS
Hesiod calls may fail because of:
ENOMEM Insufficient memory was available to carry out the
requested operation.
ENOEXEC
_h_e_s_i_o_d___i_n_i_t failed because the Hesiod configuration
file was invalid.
ECONNREFUSED
_h_e_s_i_o_d___r_e_s_o_l_v_e failed because no name server could
be contacted to answer the query.
EMSGSIZE
_h_e_s_i_o_d___r_e_s_o_l_v_e failed because the query or response
was too big to fit into the packet buffers.
ENOENT _h_e_s_i_o_d___r_e_s_o_l_v_e failed because the name server had
no text 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 the _n_a_m_e argument had a
domain extension which could not be resolved with
type ``rhs-extension'' in the local Hesiod domain.
AAUUTTHHOORR
Steve Dyer, IBM/Project Athena
Greg Hudson, MIT Team Athena
Copyright 1987, 1988, 1995, 1996 by the Massachusetts
Institute of Technology.
BBUUGGSS
The strings corresponding to the _e_r_r_n_o values set by the
Hesiod functions are not particularly indicative of what
went wrong, especially for _E_N_O_E_X_E_C and _E_N_O_E_N_T.
30 November 1996 2