hesiod, hesiod_init, hesiod_resolve, hesiod_free_list, hesiod_to_bind,
hesiod_end - Hesiod name server interface library
Standard C Library (libc, -lc)
**hesiod_resolve(void *context, const char *name, const char *type);
hesiod_free_list(void *context, char **list);
*hesiod_to_bind(void *context, const char *name, const char *type);
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 context, an opaque object
which stores information used internally by the library between calls.
hesiod_init() initializes a context, storing a pointer to the context in
the location pointed to by the context argument. hesiod_end() frees the
resources used by a context.
hesiod_resolve() is the primary interface to the library. If successful,
it returns a list of one or more strings giving the records matching name
and type. The last element of the list is followed by a NULL pointer.
It is the caller's responsibility to call hesiod_free_list() to free the
resources used by the returned list.
hesiod_to_bind() converts name and type into the DNS name used by
hesiod_resolve(). It is the caller's responsibility to free the returned
string using free(3).
If successful, hesiod_init() returns 0; otherwise it returns -1 and sets
errno to indicate the error. On failure, hesiod_resolve() and
hesiod_to_bind() return NULL and set the global variable errno to indicate
If the environment variable HES_DOMAIN is set, it will override the
domain in the Hesiod configuration file. If the environment variable
HESIOD_CONFIG is set, it specifies the location of the Hesiod configuration
Hesiod calls may fail because of:
ENOMEM Insufficient memory was available to carry out the
ENOEXEC hesiod_init() failed because the Hesiod configuration file
ECONNREFUSED hesiod_resolve() failed because no name server could be
contacted to answer the query.
EMSGSIZE hesiod_resolve() or hesiod_to_bind() failed because the
query or response was too big to fit into the packet
ENOENT hesiod_resolve() failed because the name server had no text
records matching name and type, or hesiod_to_bind() failed
because the name argument had a domain extension which
could not be resolved with type ``rhs-extension'' in the
local Hesiod domain.
Hesiod - Project Athena Technical Plan -- Name Service.
Steve Dyer, IBM/Project Athena
Greg Hudson, MIT Team Athena
Copyright 1987, 1988, 1995, 1996 by the Massachusetts Institute of Technology.
The strings corresponding to the errno values set by the Hesiod functions
are not particularly indicative of what went wrong, especially for
ENOEXEC and ENOENT.
BSD September 16, 2001 BSD
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