# snmpa_mib_storage

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Module

snmpa_mib_storage

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Module Summary

Behaviour module for the SNMP agent mib storage.

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Since

Module snmpa_mib_storage was introduced in OTP R16B01.

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Description

This module defines the behaviour of the SNMP agent mib storage.

The mib storage is used by the agent to store internal mib- related information. The mib storage module is used by several entities, not just the mib-server.

A snmpa_mib_storage compliant module must export the following functions:

- open/5
- close/1
- read/2
- write/2
- delete/1
- delete/2
- match_object/2
- match_delete/2
- tab2list/1
- info/1
- sync/1
- backup/2

The semantics of them and their exact signatures are explained below.

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CALLBACK FUNCTIONS

The following functions must be exported from a mib-server data callback module:

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Exports

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Module:open(Name, RecordName, Fields, Type, Options) -> {ok, TabId} | {error, Reason}
OTP R16B01

### Types

Name = atom()
RecordName = atom()
Fields = [atom()]
Type = set | bag()
Options = list()
TabId = term()
Reason = term()

Create or open a mib storage table.

Note that the RecordName and Fields arguments my not be used in all implementations (they are actually only needed for mnesia-based implementations).

Note also that the Options argument comes from the options config option of the mib-storage config option, and is passed on as is.

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Module:close(TabId) -> void()
OTP R16B01

### Types

State = term()

Close the mib-storage table.

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Module:read(TabId, Key) -> false | {value, Record}
OTP R16B01

### Types

TabId = term()
Key = term()
Record = tuple()

Read a record from the mib-storage table.

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Module:write(TabId, Record) -> ok | {error, Reason}
OTP R16B01

### Types

TabId = term()
Record = tuple()
Reason = term()

Write a record to the mib-storage table.

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Module:delete(TabId) -> void()
OTP R16B01

### Types

TabId = term()

Delete an entire mib-storage table.

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Module:delete(TabId, Key) -> ok | {error, Reason}
OTP R16B01

### Types

TabId = term()
Key = term()
Reason = term()

Delete a record from the mib-storage table.

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Module:match_object(TabId, Pattern) -> Recs | {error, Reason}
OTP R16B01

### Types

TabId = term()
Pattern = match_pattern()
Recs = [tuple()]
Reason = term()

Search the mib-storage table for record that match the specified pattern.

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Module:match_delete(TabId, Pattern) -> Recs | {error, Reason}
OTP R16B01

### Types

TabId = term()
Pattern = match_pattern()
Recs = [tuple()]
Reason = term()

Search the mib-storage table for record that match the specified pattern and then delete them. The records deleted are also returned.

####
Module:tab2list(TabId) -> Recs
OTP R16B01

### Types

TabId = term()
Recs = [tuple()]

Return all records in the mib-storage table in the form of a list.

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Module:info(TabId) -> {ok, Info} | {error, Reason}
OTP R16B01

### Types

TabId = term()
Info = term()
Reason = term()

Retrieve implementation dependent mib-storage table information.

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Module:sync(TabId) -> void()
OTP R16B01

### Types

TabId = term()

Synchronize the mib-storage table.

What this means, if anything, is implementation dependent.

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Module:backup(TabId, BackupDir) -> ok | {error, Reason}
OTP R16B01

### Types

TabId = term()
BackupDir = string()
Reason = term()

Perform a backup of the mib-storage table.

What this means, if anything, is implementation dependent.