Difference between revisions of "Agent Helpers"
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Revision as of 16:04, 13 July 2011
Net-SNMP Agent Helpers
The Net-SNMP agent library provides several special purpose Handlers to reduce the work needed to implement a MIB module. See the Agent Architecture documentation for details on how the handler system is implemented within the Net-SNMP Agent. The FAQ item "What's the difference between the various mib2c configuration files?" gives an overview of the major mib2c-related helpers. The the doxygen generated documentation for the helpers are also useful documents]
Here is a list of all current helpers, by file name as found in agent/helpers/, organized by type:
| Handler call flow | |
| baby_steps | Calls your handler in baby_steps for set processing. |
| bulk_to_next | Convert GETBULK requests into GETNEXT requests for the handler. |
| mode_end_call | At the end of a series of requests, call another handler hook. |
| multiplexer | Splits mode requests into calls to different handlers. |
| row_merge | Calls sub handlers with request for one row at a time. |
| serialize | Calls sub handlers one request at a time. |
| Scalar related | |
| instance | Process individual MIB instances easily. |
| scalar | Process scalars easily. |
| scalar_group | Process groups of scalars. |
| Table related | |
| row_merge | Calls sub handlers with request for one row at a time. |
| table | Helps you implement a table. |
| table_container | Helps you implement a table when data can be found via a netsnmp_container. |
| table_data | Helps you implement a table with datamatted storage. |
| table_dataset | Helps you implement a table with automatted storage. |
| table_generic | General requirements for a table helper. |
| table_iterator | The table iterator helper is designed to simplify the task of writing a table handler for the net-snmp agent when the data being accessed is not in an oid sorted form and must be accessed externally. |
| table_row | Helps you implement a table shared across two or more subagents, or otherwise split into individual row slices. |
| table_tdata | Implement a table with datamatted storage.
|
| Data caching | |
| cache_handler | |
| stash_cache | Automatically caches data for certain handlers. |
| stash_to_next | Convert GET_STASH requests into GETNEXT requests for the handler.
|
| Miscellaneous | |
| debug_handler | Print out debugging information about the handler chain being called. |
| old_api | Calls mib module code written in the old style of code. |
| read_only | Make your handler read_only automatically The only purpose of this handler is to return an appropriate error for any requests passed to it in a SET mode. |
| null | The null helper doesn't provide any values, all requests are answered with NOSUCHVALUE |
| watcher | Watch a specified variable and process it as an instance or scalar object. |
| Deprecated/Legacy Helpers | |
| table_array | |
