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 infor-
mation, 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 information 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 argument. _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 element 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 specifies the location of the Hesiod configu-
ration file.
SSEEEE AALLSSOO
`Hesiod - Project Athena Technical Plan -- Name Service'
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 func-
tions 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 HESIOD(3)