hesiod, hesiod_init, hesiod_resolve, hesiod_free_list, hesiod_to_bind,
hesiod_end -- Hesiod name server interface library
Standard C Library (libc, -lc)
#include <hesiod.h>
int
hesiod_init(void **context);
char **
hesiod_resolve(void *context, const char *name, const char *type);
void
hesiod_free_list(void *context, char **list);
char *
hesiod_to_bind(void *context, const char *name, const char *type);
void
hesiod_end(void *context);
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.
The hesiod_init() function initializes a context, storing a pointer to
the context in the location pointed to by the context argument. The
hesiod_end() function frees the resources used by a context.
The hesiod_resolve() function 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.
The hesiod_to_bind() function 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().
The hesiod_init() function returns the value 0 if successful; otherwise
the value -1 is returned and the global variable errno is set to indicate
the error. On failure, hesiod_resolve() and hesiod_to_bind() return NULL
and set the global variable errno to indicate the error.
HES_DOMAIN If the environment variable HES_DOMAIN is set, it will
override the domain in the Hesiod configuration file.
HESIOD_CONFIG If the environment variable HESIOD_CONFIG is set, it specifies
the location of the Hesiod configuration file.
hesiod.conf(5), named(8)
Hesiod - Project Athena Technical Plan -- Name Service.
Hesiod calls may fail because of:
[ENOMEM] Insufficient memory was available to carry out the
requested operation.
[ENOEXEC] The hesiod_init() function failed because the Hesiod
configuration file was invalid.
[ECONNREFUSED] The hesiod_resolve() function failed because no name
server could be contacted to answer the query.
[EMSGSIZE] The hesiod_resolve() or hesiod_to_bind() function
failed because the query or response was too big to
fit into the packet buffers.
[ENOENT] The hesiod_resolve() function 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.
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.
FreeBSD 5.2.1 November 30, 1996 FreeBSD 5.2.1 [ Back ] |