HESIOD(3) Library Functions Manual HESIOD(3)
hesiod, hesiod_init, hesiod_resolve, hesiod_free_list, hesiod_to_bind, hesiod_end - Hesiod name server interface library
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)
cc file.c -lhesiod
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 match-
ing 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.
If successful, hesiod_init returns 0; otherwise it returns -1 and sets errno to indicate the error. On failure, hesiod_resolve and hes-
iod_to_bind return NULL and set the global variable errno to indicate the error.
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 file.
`Hesiod - Project Athena Technical Plan -- Name Service', named(8), hesiod.conf(5)
Hesiod calls may fail because of:
ENOMEM Insufficient memory was available to carry out the requested operation.
hesiod_init failed because the Hesiod configuration file was invalid.
hesiod_resolve failed because no name server could be contacted to answer the query.
hesiod_resolve or hesiod_to_bind failed because the query or response was too big to fit into the packet buffers.
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.
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.
30 November 1996 HESIOD(3)