Initialisation and Shutdown

void netsnmp_init_mib(void);
void shutdown_mib(void);

Reading and Parsing MIBs

int add_module_replacement(const char *old_module,
const char *new_module,
const char *tag, int len);

void snmp_set_mib_warnings(int level);
void snmp_set_mib_errors(int level);
void snmp_set_save_descriptions(int save);

Searching the MIB Tree

Output

void print_objid(const oid *objid, size_t objidlen);
void fprint_objid(FILE *fp,
const oid *objid, size_t objidlen);
int snprint_objid(char *buf, size_t len,
const oid *objid, size_t objidlen);

void print_description(const oid *objid, size_t objidlen, int width);
void fprint_description(FILE *fp,
const oid *objid, size_t objidlen, int width);
int snprint_description(char *buf, size_t len,
const oid *objid, size_t objidlen, int width);

Initialisation and Shutdown

netsnmp_init_mib configures the MIB directory search path (using add_mibdir ), sets up the internal MIB framework, and then loads the appropriate MIB modules (using netsnmp_read_module and read_mib). See the ENVIRONMENTAL VARIABLES section for details.
It should be called before any other routine that manipulates or accesses the MIB tree (but after any additional add_mibdir calls).

shutdown_mib will clear the information that was gathered by netsnmp_read_module, add_mibdir and add_module_replacement. It is strongly recommended that one does not invoke shutdown_mib while there are SNMP sessions being actively managed.

Reading and Parsing MIBs

read_mib is similar, but takes the name of the file containing the MIB module. Note that this file need not be located within the MIB directory search list (although any modules listed in the IMPORTS clause do).

read_all_mibs will read in all the MIB modules found on the MIB directory search list.

In general the parser is silent about what strangenesses it sees in the MIB files. To get warnings reported, call snmp_set_mib_warnings with a level of 1 (or 2 for even more warnings).

add_module_replacement can be used to allow new MIB modules to obsolete older ones, without needing to amend the IMPORTS clauses of other modules. It takes the names of the old and new modules, together with an indication of which portions of the old module are affected.

Searching the MIB Tree

snmp_parse_oid is similar, but returns a pointer to the parsed OID buffer (or NULL).

get_module_node takes a descriptor and the name of a module, and returns the corresponding oid list, in the same way as read_objid above.
If the module name is specified as "ANY", then this routine will assume that the descriptor given is unique within the tree, and will return the matching entry. If this assumption is invalid, then the behaviour as to which variable is returned is implementation dependent.

Output

print_objid will take an object identifier (as returned by read_objid, snmp_parse_oid or get_module_node), and prints the textual form of this OID to the standard output.

fprint_objid does the same, but prints to the FILE pointer specified by the initial parameter.

snprint_objid prints the same information into the buffer pointed to by buf which is of length len. It returns the number of characters printed, or -1 if the buffer was not large enough. In the latter case, buf will typically contain a truncated version of the information (but this behaviour is not guaranteed).

print_description, fprint_description, and snprint_description take a similar object identifier and print out a version of the MIB definition for that object, together with the full OID. The width argument controls how the OID is layed out.

By default the parser does not save descriptions since they may be huge. In order to be able to print them, it is necessary to invoke snmp_set_save_descriptions(1)before calling init_mib (or similar).