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# View Source snmpm (snmp v5.18.2)

Interface functions to the SNMP toolkit manager

The module `snmpm` contains interface functions to the SNMP manager.

# Summary

## Types

agent_config()
agent_config_item()

Value type depend on the item according to

pdu_type()
register_timeout()

The time to complete a (agent) registration.

request_id()

Is a unique term that identifies a request.

snmp_reply()
snmpm_user()

Module implementing the snmpm_user behaviour.

target_name()

Is a unique non-empty string.

user_id()

Is a unique term that identifies a user.

usm_config_item()

Value type depend on the item according to

value_type()

- `o - 'OBJECT IDENTIFIER'`

var_and_val()

## Functions

agent_info(TargetName, Item)

Retrieve agent config.

async_get2(UserId, TargetName, Oids)

Equivalent to `async_get2/4`.

async_get2(UserId, TargetName, Oids, SendOpts)

Asynchronous `get-request`.

async_get_bulk2(UserId, TargetName, NonRep, MaxRep, Oids)

Equivalent to `async_get_bulk2/6`.

async_get_bulk2(UserId, TargetName, NonRep, MaxRep, Oids, SendOpts)

Asynchronous `get-bulk-request` (See RFC1905).

async_get_next2(UserId, TargetName, Oids)

Equivalent to `async_get_next2/4`.

async_get_next2(UserId, TargetName, Oids, SendOpts)

Asynchronous `get-next-request`.

async_set2(UserId, TargetName, VarsAndVals)

Equivalent to `async_set2/4`.

async_set2(UserId, TargetName, VarsAndVals, SendOpts)

Asynchronous `set-request`.

backup(BackupDir)

Backup persistent data handled by the manager.

cancel_async_request(UserId, ReqId)

Cancel a previous asynchronous request.

cancel_notify_started(Pid)

Cancel a previous request to be notified of SNMP manager start.

change_log_size(NewSize)

Changes the log size of the Audit Trail Log. The application must be configured to use the audit trail log function. Please refer to disk_log(3) in Kernel Reference Manual for a description of how to change the log size.

demonitor(Ref)

Turn off monitoring of the SNMP manager.

format_reason(Reason)

Equivalent to `format_reason/2`.

format_reason(Prefix, Reason)

This utility function is used to create a formatted (pretty printable) string of the error reason received from either

info()

Returns a list (a dictionary) containing information about the manager. Information includes statistics counters, miscellaneous info about each process (e.g. memory allocation), and so on.

load_mib(MibName)

Load a `Mib` into the manager. The `MibName` is the name of the Mib, including the path to where the compiled mib is found. For example,

log_to_io(LogDir)

Equivalent to `log_to_io/7`.

log_to_io/2

Equivalent to `log_to_io/7`.

log_to_io/3

Equivalent to `log_to_io/7`.

log_to_io/4

Equivalent to `log_to_io/7`.

log_to_io/5

Equivalent to `log_to_io/7`.

log_to_io/6

Equivalent to `log_to_io/7`.

log_to_io(LogDir, Mibs, LogName, LogFile, Block, Start, Stop)

Converts an Audit Trail Log to a readable format and prints it on stdio. `LogName` defaults to "snmpm_log". `LogFile` defaults to "snmpm.log".

log_to_txt(LogDir)

Equivalent to `log_to_txt/8`.

log_to_txt/2

Equivalent to `log_to_txt/8`.

log_to_txt/3

Equivalent to `log_to_txt/8`.

log_to_txt/4

Equivalent to `log_to_txt/8`.

log_to_txt/5

Equivalent to `log_to_txt/8`.

log_to_txt/6

Equivalent to `log_to_txt/8`.

log_to_txt/7

Equivalent to `log_to_txt/8`.

log_to_txt(LogDir, Mibs, OutFile, LogName, LogFile, Block, Start, Stop)

Converts an Audit Trail Log to a readable text file. `OutFile` defaults to "./snmpm_log.txt". `LogName` defaults to "snmpm_log". `LogFile` defaults to "snmpm.log".

monitor()

Monitor the SNMP manager. In case of a crash, the calling (monitoring) process will get a 'DOWN' message (see the erlang module for more info).

name_to_oid(AliasName)

Transform a alias-name to its oid.

notify_started(Timeout)

Request a notification (message) when the SNMP manager has started.

oid_to_name(OID)

Transform a oid to its aliasname.

oid_to_type(OID)

Retrieve the type (asn1 bertype) of an oid.

register_agent(UserId, TargetName, Config)

Explicitly instruct the manager to handle this agent, with `UserId` as the responsible user.

register_user(UserId, Module, Data)

Equivalent to `register_user/4`.

register_user(UserId, Module, Data, DefaultAgentConfig)

Register the manager entity (=user) responsible for specific agent(s).

register_user_monitor(UserId, Module, Data)

Equivalent to `register_user_monitor/4`.

register_user_monitor(UserId, Module, Data, DefaultAgentConfig)

Register the monitored manager entity (=user) responsible for specific agent(s).

register_usm_user(EngineID, UserName, Config)

Explicitly instruct the manager to handle this USM user. Note that there is an alternate way to do the same thing: Add the usm user to the manager config files (see usm.conf).

restart(What)

Restart the indicated process (`What`). Note that its not without risk to restart a process, and should therefore be used with care.

set_log_type(NewType)

Changes the run-time Audit Trail log type.

sync_get2(UserId, TargetName, Oids)

Equivalent to `sync_get2/4`.

sync_get2(UserId, TargetName, Oids, SendOpts)

Synchronous `get-request`.

sync_get_bulk2(UserId, TargetName, NonRep, MaxRep, Oids)

Equivalent to `sync_get_bulk2/6`.

sync_get_bulk2(UserId, TargetName, NonRep, MaxRep, Oids, SendOpts)

Synchronous `get-bulk-request` (See RFC1905).

sync_get_next2(UserId, TargetName, Oids)

Equivalent to `sync_get_next2/4`.

sync_get_next2(UserId, TargetName, Oids, SendOpts)

Synchronous `get-next-request`.

sync_set2(UserId, TargetName, VarsAndVals)

Equivalent to `sync_set2/4`.

sync_set2(UserId, TargetName, VarsAndVals, SendOpts)

Synchronous `set-request`.

unload_mib(MibName)

Unload a `Mib` from the manager. The `MibName` is the name of the Mib, including the path to where the compiled mib is found. For example,

unregister_agent(UserId, TargetName)

Unregister the agent.

unregister_user(UserId)

Unregister the user.

unregister_usm_user(EngineID, UserName)

Unregister this USM user.

update_agent_info(UserId, TargetName, Info)

Update agent config.

update_agent_info(UserId, TargetName, Item, Value)

Update agent config.

update_usm_user_info(EngineID, UserName, Item, Value)

Update usm user config.

usm_user_info(EngineID, UserName, Item)

Retrieve usm user config.

verbosity(Target, Verbosity)

Sets verbosity for the designated process. For the lowest verbosity `silence`, nothing is printed. The higher the verbosity, the more is printed.

which_agents()

Equivalent to `which_agents/1`.

which_agents(UserId)

Get a list of all registered agents or all agents registered by a specific user.

which_mibs()

Get a list of all the mib's loaded into the manager.

which_users()

Get a list of the identities of all registered users.

which_usm_users()

Get a list of all registered usm users.

which_usm_users(EngineID)

Get a list of all registered usm users with engine-id `EngineID`.

# Types

# agent_config()

    -type agent_config() ::
              {engine_id, snmp:engine_id()} |
              {address, inet:ip_address()} |
              {port, inet:port_number()} |
              {tdomain, snmp:tdomain()} |
              {community, snmp:community()} |
              {timeout, register_timeout()} |
              {max_message_size, snmp:mms()} |
              {version, snmp:version()} |
              {sec_model, snmp:sec_model()} |
              {sec_name, snmp:sec_name()} |
              {sec_level, snmp:sec_level()}.

# agent_config_item()

    -type agent_config_item() ::
              engine_id | address | port | tdomain | community | timeout | max_message_size | version |
              sec_model | sec_name | sec_level.

Value type depend on the item according to:

- `engine_id` - Engine ID of the agent.

  Value type: engine_id()

- `address` - The IP address of the agent.

  Value type: ip_address()

- `port` - Port number of the agent.

  Value type: port_number()

- `tdomain` - Transport domain.

  Value type: tdomain()

- `community` - Community.

  Value type: community()

- `timeout` - Registration timeout.

  Value type: `register_timeout/0`

- `max_message_size` - Max Message Size of a message.

  Value type: mms()

- `version` - What SNMP version is used when communicating with this agent.

  Value type: version()

- `sec_model` - Security Model.

  Value type: sec_model()

- `sec_name` - Security Name.

  Value type: sec_name()

- `sec_level` - Security Level.

  Value type: sec_level()

# pdu_type()

    -type pdu_type() :: snmp:pdu_type() | trappdu.

# register_timeout()

    -type register_timeout() :: pos_integer() | snmp:snmp_timer().

The time to complete a (agent) registration.

# request_id()

    -opaque request_id()

Is a unique term that identifies a request.

# snmp_reply()

    -type snmp_reply() :: {snmp:error_status(), snmp:error_index(), [snmp:varbind()]}.

# snmpm_user()

    -type snmpm_user() :: module().

Module implementing the snmpm_user behaviour.

# target_name()

    -type target_name() :: string().

Is a unique non-empty string.

# user_id()

    -type user_id() :: term().

Is a unique term that identifies a user.

# usm_config_item()

    -type usm_config_item() :: sec_name | auth | auth_key | priv | priv_key.

Value type depend on the item according to:

- `sec_name` - Security Name.

  Value type: `snmp:sec_name()`

- `auth` - Authentication protocol.

  Value type: `snmp:usm_auth_protocol()`

- `auth_key` - Authentication key.

  Value type: `snmp:usm_auth_key()`

- `priv` - Privacy protocol.

  Value type: `snmp:usm_priv_protocol()`

- `priv_key` - Privacy key.

  Value type: `snmp:usm_priv_key()`

# value_type()

    -type value_type() :: o | i | u | g | s | s | b | ip | op | c32 | c64 | tt.

- `o - 'OBJECT IDENTIFIER'`

- `i - 'INTEGER'`

- `u - 'Unsigned32`

- `g - 'Unsigned32'`

- `s - 'OCTET STRING'`

- `b - 'BITS'`

- `ip - 'IpAddress'`

- `op - 'Opaque'`

- `c32 - 'Counter32'`

- `c64 - 'Counter64'`

- `tt - 'TimeTicks'`

# var_and_val()

    -type var_and_val() ::
              {OID :: snmp:oid(), ValueType :: value_type(), Value :: term()} |
              {OID :: snmp:oid(), Value :: term()}.

# Functions

# agent_info(TargetName, Item)

    -spec agent_info(TargetName, Item) -> {ok, Value} | {error, Reason}
                        when
                            TargetName :: target_name(),
                            Item :: agent_config_item(),
                            Value :: term(),
                            Reason :: term().

Retrieve agent config.

# async_get2(UserId, TargetName, Oids)

(since OTP R14B03)

    -spec async_get2(UserId, TargetName, Oids) -> {ok, ReqId} | {error, Reason}
                        when
                            UserId :: user_id(),
                            TargetName :: target_name(),
                            Oids :: [snmp:oid()],
                            ReqId :: request_id(),
                            Reason :: term().

Equivalent to `async_get2/4`.

# async_get2(UserId, TargetName, Oids, SendOpts)

(since OTP R14B03)

    -spec async_get2(UserId, TargetName, Oids, SendOpts) -> {ok, ReqId} | {error, Reason}
                        when
                            UserId :: user_id(),
                            TargetName :: target_name(),
                            Oids :: [snmp:oid()],
                            SendOpts :: [SendOpt],
                            SendOpt ::
                                {context, snmp:context_name()} |
                                {timeout, pos_integer()} |
                                {community, snmp:community()} |
                                {sec_model, snmp:sec_model()} |
                                {sec_name, snmp:sec_name()} |
                                {sec_level, snmp:sec_level()} |
                                {max_message_size, snmp:mms()} |
                                {extra, term()},
                            ReqId :: request_id(),
                            Reason :: term().

Asynchronous `get-request`.

The reply, if it arrives, will be delivered to the user through a call to the `snmpm_user` callback function `handle_pdu`.

The send option `timeout` specifies for how long the request is valid (after which the manager is free to delete it).

The send option `extra` specifies an opaque data structure passed on to the net-if process. The net-if process included in this application makes, with one exception, no use of this info, so the only use for it (when using the built in net-if) would be tracing. The one usage exception is: Any tuple with `snmpm_extra_info_tag` as its first element is reserved for internal use.

Some of the send options (`community`, `sec_model`, `sec_name`, `sec_level` and `max_message_size`) are `override options`. That is, for this request, they override any configuration done when the agent was registered.

# async_get_bulk2(UserId, TargetName, NonRep, MaxRep, Oids)

(since OTP R14B03)

    -spec async_get_bulk2(UserId, TargetName, NonRep, MaxRep, Oids) -> {ok, ReqId} | {error, Reason}
                             when
                                 UserId :: user_id(),
                                 TargetName :: target_name(),
                                 NonRep :: non_neg_integer(),
                                 MaxRep :: non_neg_integer(),
                                 Oids :: [snmp:oid()],
                                 ReqId :: request_id(),
                                 Reason :: term().

Equivalent to `async_get_bulk2/6`.

# async_get_bulk2(UserId, TargetName, NonRep, MaxRep, Oids, SendOpts)

(since OTP R14B03)

    -spec async_get_bulk2(UserId, TargetName, NonRep, MaxRep, Oids, SendOpts) ->
                             {ok, ReqId} | {error, Reason}
                             when
                                 UserId :: user_id(),
                                 TargetName :: target_name(),
                                 NonRep :: non_neg_integer(),
                                 MaxRep :: non_neg_integer(),
                                 Oids :: [snmp:oid()],
                                 SendOpts :: [SendOpt],
                                 SendOpt ::
                                     {context, snmp:context_name()} |
                                     {timeout, pos_integer()} |
                                     {community, snmp:community()} |
                                     {sec_model, snmp:sec_model()} |
                                     {sec_name, snmp:sec_name()} |
                                     {sec_level, snmp:sec_level()} |
                                     {max_message_size, snmp:mms()} |
                                     {extra, term()},
                                 ReqId :: request_id(),
                                 Reason :: term().

Asynchronous `get-bulk-request` (See RFC1905).

The reply, if it arrives, will be delivered to the user through a call to the `snmpm_user` callback function `handle_pdu`.

The send option `timeout` specifies for how long the request is valid (after which the manager is free to delete it).

The send option `extra` specifies an opaque data structure passed on to the `net-if` process. The `net-if` process included in this application makes no use of this info, so the only use for it in such a configuration (when using the built in `net-if`) would be tracing.

Some of the send options (`community`, `sec_model`, `sec_name`, `sec_level` and `max_message_size`) are `override options`. That is, for this request, they override any configuration done when the agent was registered.

# async_get_next2(UserId, TargetName, Oids)

(since OTP R14B03)

    -spec async_get_next2(UserId, TargetName, Oids) -> {ok, ReqId} | {error, Reason}
                             when
                                 UserId :: user_id(),
                                 TargetName :: target_name(),
                                 Oids :: [snmp:oid()],
                                 ReqId :: request_id(),
                                 Reason :: term().

Equivalent to `async_get_next2/4`.

# async_get_next2(UserId, TargetName, Oids, SendOpts)

(since OTP R14B03)

    -spec async_get_next2(UserId, TargetName, Oids, SendOpts) -> {ok, ReqId} | {error, Reason}
                             when
                                 UserId :: user_id(),
                                 TargetName :: target_name(),
                                 Oids :: [snmp:oid()],
                                 SendOpts :: [SendOpt],
                                 SendOpt ::
                                     {context, snmp:context_name()} |
                                     {timeout, pos_integer()} |
                                     {community, snmp:community()} |
                                     {sec_model, snmp:sec_model()} |
                                     {sec_name, snmp:sec_name()} |
                                     {sec_level, snmp:sec_level()} |
                                     {max_message_size, snmp:mms()} |
                                     {extra, term()},
                                 ReqId :: request_id(),
                                 Reason :: term().

Asynchronous `get-next-request`.

The reply, if it arrives, will be delivered to the user through a call to the `snmpm_user` callback function `handle_pdu`.

The send option `timeout` specifies for how long the request is valid (after which the manager is free to delete it).

The send option `extra` specifies an opaque data structure passed on to the `net-if` process. The `net-if` process included in this application makes, with one exception, no use of this info, so the only use for it (when using the built in `net-if`) would be tracing. The one usage exception is: Any tuple with `snmpm_extra_info_tag` as its first element is reserved for internal use.

Some of the send options (`community`, `sec_model`, `sec_name`, `sec_level` and `max_message_size`) are `override options`. That is, for this request, they override any configuration done when the agent was registered.

# async_set2(UserId, TargetName, VarsAndVals)

(since OTP R14B03)

    -spec async_set2(UserId, TargetName, VarsAndVals) -> {ok, ReqId} | {error, Reason}
                        when
                            UserId :: user_id(),
                            TargetName :: target_name(),
                            VarsAndVals :: [var_and_val()],
                            ReqId :: request_id(),
                            Reason :: term().

Equivalent to `async_set2/4`.

# async_set2(UserId, TargetName, VarsAndVals, SendOpts)

(since OTP R14B03)

    -spec async_set2(UserId, TargetName, VarsAndVals, SendOpts) -> {ok, ReqId} | {error, Reason}
                        when
                            UserId :: user_id(),
                            TargetName :: target_name(),
                            VarsAndVals :: [var_and_val()],
                            SendOpts :: [SendOpt],
                            SendOpt ::
                                {context, snmp:context_name()} |
                                {timeout, pos_integer()} |
                                {community, snmp:community()} |
                                {sec_model, snmp:sec_model()} |
                                {sec_name, snmp:sec_name()} |
                                {sec_level, snmp:sec_level()} |
                                {max_message_size, snmp:mms()} |
                                {extra, term()},
                            ReqId :: request_id(),
                            Reason :: term().

Asynchronous `set-request`.

The reply will be delivered to the user through a call to the `snmpm_user` callback function `handle_pdu`.

The send option `timeout` specifies for how long the request is valid (after which the manager is free to delete it).

When var_and_val() is {oid(), value()}, the manager makes an educated guess based on the loaded mibs.

The send option `extra` specifies an opaque data structure passed on to the net-if process. The net-if process included in this application makes, with one exception, no use of this info, so the only use for it (when using the built in net-if) would be tracing. The one usage exception is: Any tuple with `snmpm_extra_info_tag` as its first element is reserved for internal use.

Some of the send options (`community`, `sec_model`, `sec_name`, `sec_level` and `max_message_size`) are `override options`. That is, for this request, they override any configuration done when the agent was registered.

# backup(BackupDir)

    -spec backup(BackupDir) -> ok | {error, Reason} when BackupDir :: snmp:dir(), Reason :: term().

Backup persistent data handled by the manager.

BackupDir cannot be identical to DbDir.

# cancel_async_request(UserId, ReqId)

    -spec cancel_async_request(UserId, ReqId) -> ok | {error, Reason}
                                  when UserId :: user_id(), ReqId :: request_id(), Reason :: term().

Cancel a previous asynchronous request.

# cancel_notify_started(Pid)

    -spec cancel_notify_started(Pid) -> snmp:void() when Pid :: pid().

Cancel a previous request to be notified of SNMP manager start.

# change_log_size(NewSize)

    -spec change_log_size(NewSize) -> ok | {error, Reason} when NewSize :: snmp:log_size(), Reason :: term().

Changes the log size of the Audit Trail Log. The application must be configured to use the audit trail log function. Please refer to disk_log(3) in Kernel Reference Manual for a description of how to change the log size.

The change is permanent, as long as the log is not deleted. That means, the log size is remembered across reboots.

# demonitor(Ref)

    -spec demonitor(Ref) -> true when Ref :: reference().

Turn off monitoring of the SNMP manager.

# format_reason(Reason)

    -spec format_reason(Reason) -> FReason when Reason :: term(), FReason :: string().

Equivalent to `format_reason/2`.

# format_reason(Prefix, Reason)

    -spec format_reason(Prefix, Reason) -> FReason
                           when
                               Prefix :: non_neg_integer() | string(), Reason :: term(), FReason :: string().

This utility function is used to create a formatted (pretty printable) string of the error reason received from either:

- The `Reason` returned value if any of the sync/async get/get-next/set/get-bulk functions returns `{error, Reason}`
- The `Reason` parameter in the handle_error user callback function.

`Prefix` should either be an indentation string (e.g. a list of spaces) or a positive integer (which will be used to create the indentation string of that length).

# info()

    -spec info() -> [{Key, Value}] when Key :: atom(), Value :: term().

Returns a list (a dictionary) containing information about the manager. Information includes statistics counters, miscellaneous info about each process (e.g. memory allocation), and so on.

# load_mib(MibName)

    -spec load_mib(MibName) -> ok | {error, Reason} when MibName :: snmp:mib_name(), Reason :: term().

Load a `Mib` into the manager. The `MibName` is the name of the Mib, including the path to where the compiled mib is found. For example,

              Dir = code:priv_dir(my_app) ++ "/mibs/",
              snmpm:load_mib(Dir ++ "MY-MIB").

# log_to_io(LogDir)

(since OTP R15B01)

    -spec log_to_io(LogDir) -> ok | {ok, Cnt} | {error, Reason}
                       when
                           LogDir :: snmp:dir(),
                           Cnt :: {NumOK, NumERR},
                           NumOK :: non_neg_integer(),
                           NumERR :: pos_integer(),
                           Reason :: term().

Equivalent to `log_to_io/7`.

# log_to_io/2

(since OTP R15B01)

    -spec log_to_io(LogDir, Block) -> ok | {ok, Cnt} | {error, Reason}
                       when
                           LogDir :: snmp:dir(),
                           Block :: boolean(),
                           Cnt :: {NumOK, NumERR},
                           NumOK :: non_neg_integer(),
                           NumERR :: pos_integer(),
                           Reason :: term();
                   (LogDir, Mibs) -> ok | {ok, Cnt} | {error, Reason}
                       when
                           LogDir :: snmp:dir(),
                           Mibs :: [snmp:mib_name()],
                           Cnt :: {NumOK, NumERR},
                           NumOK :: non_neg_integer(),
                           NumERR :: pos_integer(),
                           Reason :: term().

Equivalent to `log_to_io/7`.

# log_to_io/3

(since OTP R15B01)

    -spec log_to_io(LogDir, Mibs, Block) -> ok | {ok, Cnt} | {error, Reason}
                       when
                           LogDir :: snmp:dir(),
                           Mibs :: [snmp:mib_name()],
                           Block :: boolean(),
                           Cnt :: {NumOK, NumERR},
                           NumOK :: non_neg_integer(),
                           NumERR :: pos_integer(),
                           Reason :: term();
                   (LogDir, Mibs, LogName) -> ok | {ok, Cnt} | {error, Reason}
                       when
                           LogDir :: snmp:dir(),
                           Mibs :: [snmp:mib_name()],
                           LogName :: string(),
                           Cnt :: {NumOK, NumERR},
                           NumOK :: non_neg_integer(),
                           NumERR :: pos_integer(),
                           Reason :: term().

Equivalent to `log_to_io/7`.

# log_to_io/4

(since OTP R15B01)

    -spec log_to_io(LogDir, Mibs, LogName, Block) -> ok | {ok, Cnt} | {error, Reason}
                       when
                           LogDir :: snmp:dir(),
                           Mibs :: [snmp:mib_name()],
                           LogName :: string(),
                           Block :: boolean(),
                           Cnt :: {NumOK, NumERR},
                           NumOK :: non_neg_integer(),
                           NumERR :: pos_integer(),
                           Reason :: term();
                   (LogDir, Mibs, LogName, LogFile) -> ok | {ok, Cnt} | {error, Reason}
                       when
                           LogDir :: snmp:dir(),
                           Mibs :: [snmp:mib_name()],
                           LogName :: string(),
                           LogFile :: string(),
                           Cnt :: {NumOK, NumERR},
                           NumOK :: non_neg_integer(),
                           NumERR :: pos_integer(),
                           Reason :: term().

Equivalent to `log_to_io/7`.

# log_to_io/5

(since OTP R15B01)

    -spec log_to_io(LogDir, Mibs, LogName, LogFile, Block) -> ok | {ok, Cnt} | {error, Reason}
                       when
                           LogDir :: snmp:dir(),
                           Mibs :: [snmp:mib_name()],
                           LogName :: string(),
                           LogFile :: string(),
                           Block :: boolean(),
                           Cnt :: {NumOK, NumERR},
                           NumOK :: non_neg_integer(),
                           NumERR :: pos_integer(),
                           Reason :: term();
                   (LogDir, Mibs, LogName, LogFile, Start) -> ok | {ok, Cnt} | {error, Reason}
                       when
                           LogDir :: snmp:dir(),
                           Mibs :: [snmp:mib_name()],
                           LogName :: string(),
                           LogFile :: string(),
                           Start :: null | snmp:log_time(),
                           Cnt :: {NumOK, NumERR},
                           NumOK :: non_neg_integer(),
                           NumERR :: pos_integer(),
                           Reason :: term().

Equivalent to `log_to_io/7`.

# log_to_io/6

(since OTP R15B01)

    -spec log_to_io(LogDir, Mibs, LogName, LogFile, Block, Start) -> ok | {ok, Cnt} | {error, Reason}
                       when
                           LogDir :: snmp:dir(),
                           Mibs :: [snmp:mib_name()],
                           LogName :: string(),
                           LogFile :: string(),
                           Block :: boolean(),
                           Start :: null | snmp:log_time(),
                           Cnt :: {NumOK, NumERR},
                           NumOK :: non_neg_integer(),
                           NumERR :: pos_integer(),
                           Reason :: term();
                   (LogDir, Mibs, LogName, LogFile, Start, Stop) -> ok | {ok, Cnt} | {error, Reason}
                       when
                           LogDir :: snmp:dir(),
                           Mibs :: [snmp:mib_name()],
                           LogName :: string(),
                           LogFile :: string(),
                           Start :: null | snmp:log_time(),
                           Stop :: null | snmp:log_time(),
                           Cnt :: {NumOK, NumERR},
                           NumOK :: non_neg_integer(),
                           NumERR :: pos_integer(),
                           Reason :: term().

Equivalent to `log_to_io/7`.

# log_to_io(LogDir, Mibs, LogName, LogFile, Block, Start, Stop)

(since OTP R16B03)

    -spec log_to_io(LogDir, Mibs, LogName, LogFile, Block, Start, Stop) -> ok | {ok, Cnt} | {error, Reason}
                       when
                           LogDir :: snmp:dir(),
                           Mibs :: [snmp:mib_name()],
                           LogName :: string(),
                           LogFile :: string(),
                           Block :: boolean(),
                           Start :: null | snmp:log_time(),
                           Stop :: null | snmp:log_time(),
                           Cnt :: {NumOK, NumERR},
                           NumOK :: non_neg_integer(),
                           NumERR :: pos_integer(),
                           Reason :: term().

Converts an Audit Trail Log to a readable format and prints it on stdio. `LogName` defaults to "snmpm_log". `LogFile` defaults to "snmpm.log".

The `Block` argument indicates if the log should be blocked during conversion. This could be useful when converting large logs (when otherwise the log could wrap during conversion). Defaults to `true`.

`Start` and `Stop` indicates which log entries should be converted, from when (`Start`) to when (`Stop`). `Start = null` => Start from the beginning of the log. `Stop = null` => Stop the conversion at the end of the log. Defaults to `Start = null` and `Stop = null` (the entire log).

See `snmp:log_to_io/7` for more info.

# log_to_txt(LogDir)

(since OTP R16B03)

    -spec log_to_txt(LogDir :: snmp:dir()) -> snmp:void().

Equivalent to `log_to_txt/8`.

# log_to_txt/2

    -spec log_to_txt(LogDir :: snmp:dir(), Block :: boolean()) -> snmp:void();
                    (LogDir :: snmp:dir(), Mibs :: [snmp:mib_name()]) -> snmp:void().

Equivalent to `log_to_txt/8`.

# log_to_txt/3

    -spec log_to_txt(LogDir :: snmp:dir(), Mibs :: [snmp:mib_name()], Block :: boolean()) -> snmp:void();
                    (LogDir :: snmp:dir(), Mibs :: [snmp:mib_name()], OutFile :: file:filename()) ->
                        snmp:void().

Equivalent to `log_to_txt/8`.

# log_to_txt/4

    -spec log_to_txt(LogDir :: snmp:dir(),
                     Mibs :: [snmp:mib_name()],
                     OutFile :: file:filename(),
                     Block :: boolean()) ->
                        snmp:void();
                    (LogDir :: snmp:dir(),
                     Mibs :: [snmp:mib_name()],
                     OutFile :: file:filename(),
                     LogName :: string()) ->
                        snmp:void().

Equivalent to `log_to_txt/8`.

# log_to_txt/5

    -spec log_to_txt(LogDir :: snmp:dir(),
                     Mibs :: [snmp:mib_name()],
                     OutFile :: file:filename(),
                     LogName :: string(),
                     Block :: boolean()) ->
                        snmp:void();
                    (LogDir :: snmp:dir(),
                     Mibs :: [snmp:mib_name()],
                     OutFile :: file:filename(),
                     LogName :: string(),
                     LogFile :: string()) ->
                        snmp:void().

Equivalent to `log_to_txt/8`.

# log_to_txt/6

    -spec log_to_txt(LogDir :: snmp:dir(),
                     Mibs :: [snmp:mib_name()],
                     OutFile :: file:filename(),
                     LogName :: string(),
                     LogFile :: string(),
                     Block :: boolean()) ->
                        snmp:void();
                    (LogDir :: snmp:dir(),
                     Mibs :: [snmp:mib_name()],
                     OutFile :: file:filename(),
                     LogName :: string(),
                     LogFile :: string(),
                     Start :: null | snmp:log_time()) ->
                        snmp:void().

Equivalent to `log_to_txt/8`.

# log_to_txt/7

    -spec log_to_txt(LogDir :: snmp:dir(),
                     Mibs :: [snmp:mib_name()],
                     OutFile :: file:filename(),
                     LogName :: string(),
                     LogFile :: string(),
                     Block :: boolean(),
                     Start :: null | snmp:log_time()) ->
                        snmp:void();
                    (LogDir :: snmp:dir(),
                     Mibs :: [snmp:mib_name()],
                     OutFile :: file:filename(),
                     LogName :: string(),
                     LogFile :: string(),
                     Start :: null | snmp:log_time(),
                     Stop :: null | snmp:log_time()) ->
                        snmp:void().

Equivalent to `log_to_txt/8`.

# log_to_txt(LogDir, Mibs, OutFile, LogName, LogFile, Block, Start, Stop)

(since OTP R16B03)

    -spec log_to_txt(LogDir :: snmp:dir(),
                     Mibs :: [snmp:mib_name()],
                     OutFile :: file:filename(),
                     LogName :: string(),
                     LogFile :: string(),
                     Block :: boolean(),
                     Start :: snmp:log_time(),
                     Stop :: snmp:log_time()) ->
                        snmp:void().

Converts an Audit Trail Log to a readable text file. `OutFile` defaults to "./snmpm_log.txt". `LogName` defaults to "snmpm_log". `LogFile` defaults to "snmpm.log".

The `Block` argument indicates if the log should be blocked during conversion. This could be useful when converting large logs (when otherwise the log could wrap during conversion). Defaults to `true`.

`Start` and `Stop` indicates which log entries should be converted, from when (`Start`) to when (`Stop`). `Start = null` => Start from the beginning of the log. `Stop = null` => Stop the conversion at the end of the log. Defaults to `Start = null` and `Stop = null` (the entire log).

See `snmp:log_to_txt/8` for more info.

# monitor()

    -spec monitor() -> MRef when MRef :: reference().

Monitor the SNMP manager. In case of a crash, the calling (monitoring) process will get a 'DOWN' message (see the erlang module for more info).

# name_to_oid(AliasName)

    -spec name_to_oid(AliasName) -> {ok, OIDs} | {error, Reason}
                         when AliasName :: atom(), OIDs :: [snmp:oid()], Reason :: term().

Transform a alias-name to its oid.

Note that an alias-name is only unique within the mib, so when loading several mib's into a manager, there might be several instances of the same aliasname.

# notify_started(Timeout)

    -spec notify_started(Timeout) -> Pid when Timeout :: pos_integer(), Pid :: pid().

Request a notification (message) when the SNMP manager has started.

The `Timeout` is the time the request is valid. The value has to be greater then zero.

The `Pid` is the process handling the supervision of the SNMP manager start. When the manager has started a completion message will be sent to the client from this process: `{snmpm_started, Pid}`. If the SNMP manager was not started in time, a timeout message will be sent to the client: `{snmpm_start_timeout, Pid}`.

A client application that is dependent on the SNMP manager will use this function in order to be notified of when the manager has started. There are two situations when this is useful:

- During the start of a system, when a client application could start prior to the SNMP manager but is dependent upon it, and therefore has to wait for it to start.
- When the SNMP manager has crashed, the dependent client application has to wait for the SNMP manager to be restarted before it can reconnect.

The function returns the pid() of a handler process, that does the supervision on behalf of the client application. Note that the client application is linked to this handler.

This function is used in conjunction with the monitor function.

# oid_to_name(OID)

    -spec oid_to_name(OID) -> {ok, AliasName} | {error, Reason}
                         when OID :: snmp:oid(), AliasName :: atom(), Reason :: term().

Transform a oid to its aliasname.

# oid_to_type(OID)

    -spec oid_to_type(OID) -> {ok, Type} | {error, Reason}
                         when OID :: snmp:oid(), Type :: atom(), Reason :: term().

Retrieve the type (asn1 bertype) of an oid.

# register_agent(UserId, TargetName, Config)

    -spec register_agent(UserId, TargetName, Config) -> ok | {error, Reason}
                            when
                                UserId :: user_id(),
                                TargetName :: target_name(),
                                Config :: [ConfigEntry],
                                ConfigEntry :: {Item, Value},
                                Item :: agent_config_item(),
                                Value :: term(),
                                Reason :: term().

Explicitly instruct the manager to handle this agent, with `UserId` as the responsible user.

Called to instruct the manager that this agent shall be handled. This function is used when the user knows in advance which agents the manager shall handle. Note that there is an alternate way to do the same thing: Add the agent to the manager config files (see agents.conf).

`TargetName` is a non-empty string, uniquely identifying the agent.

The type of `Val` depends on `Item`:

    [mandatory] engine_id = engine_id()
    [mandatory] address = inet:ip_address()  % Depends on tdomain
    [optional]  port = inet:port_number()
    [optional]  tdomain = snmp:tdomain()
    [optional]  community = snmp:community()
    [optional]  timeout = register_timeout()
    [optional]  max_message_size = snmp:mms()
    [optional]  version = snmp:version()
    [optional]  sec_model = snmp:sec_model()
    [optional]  sec_name = snmp:sec_name()
    [optional]  sec_level = snmp:sec_level()

Note that if no `tdomain` is given, the default value, `transportDomainUdpIpv4`, is used.

Note that if no `port` is given and if `taddress` does not contain a port number, the default value is used.

# register_user(UserId, Module, Data)

    -spec register_user(UserId, Module, Data) -> ok | {error, Reason}
                           when
                               UserId :: user_id(), Module :: snmpm_user(), Data :: term(), Reason :: term().

Equivalent to `register_user/4`.

# register_user(UserId, Module, Data, DefaultAgentConfig)

    -spec register_user(UserId, Module, Data, DefaultAgentConfig) -> ok | {error, Reason}
                           when
                               UserId :: user_id(),
                               Module :: snmpm_user(),
                               Data :: term(),
                               DefaultAgentConfig :: [DefaultConfigEntry],
                               DefaultConfigEntry :: {Item, Value},
                               Item :: agent_config_item(),
                               Value :: term(),
                               Reason :: term().

Register the manager entity (=user) responsible for specific agent(s).

`Module` is the callback module (`snmpm_user` behaviour) which will be called whenever something happens (detected agent, incoming reply or incoming trap/notification).

`Data` is an opaque data structure, not inspected by the manager, that will be included in all callback calls to the `Module` callback module (`snmpm_user` behaviour).

The argument `DefaultAgentConfig` is used as default values when this user register agents.

Note that this operation (register user) could have already been done as a consequence of the node config. (see users.conf).

# register_user_monitor(UserId, Module, Data)

    -spec register_user_monitor(UserId, Module, Data) -> ok | {error, Reason}
                                   when
                                       UserId :: user_id(),
                                       Module :: snmpm_user(),
                                       Data :: term(),
                                       Reason :: term().

Equivalent to `register_user_monitor/4`.

# register_user_monitor(UserId, Module, Data, DefaultAgentConfig)

    -spec register_user_monitor(UserId, Module, Data, DefaultAgentConfig) -> ok | {error, Reason}
                                   when
                                       UserId :: user_id(),
                                       Module :: snmpm_user(),
                                       Data :: term(),
                                       DefaultAgentConfig :: [DefaultConfigEntry],
                                       DefaultConfigEntry :: {Item, Value},
                                       Item :: agent_config_item(),
                                       Value :: term(),
                                       Reason :: term().

Register the monitored manager entity (=user) responsible for specific agent(s).

The process performing the registration will be monitored. Which means that if that process should die, all agents registered by that user process will be unregistered. All outstanding requests will be canceled.

`Module` is the callback module (`snmpm_user` behaviour) which will be called whenever something happens (detected agent, incoming reply or incoming trap/notification).

`Data` is an opaque data structure, not inspected by the manager, that will be included in all callback calls to the `Module` callback module (`snmpm_user` behaviour).

The argument `DefaultAgentConfig` is used as default values when this user register agents.

# register_usm_user(EngineID, UserName, Config)

    -spec register_usm_user(EngineID, UserName, Config) -> ok | {error, Reason}
                               when
                                   EngineID :: snmp:engine_id(),
                                   UserName :: snmp:usm_name(),
                                   Config :: [ConfigEntry],
                                   ConfigEntry :: {Item, Value},
                                   Item :: usm_config_item(),
                                   Value :: term(),
                                   Reason :: term().

Explicitly instruct the manager to handle this USM user. Note that there is an alternate way to do the same thing: Add the usm user to the manager config files (see usm.conf).

# restart(What)

(since OTP 22.3)

    -spec restart(What) -> snmp:void() when What :: net_if.

Restart the indicated process (`What`). Note that its not without risk to restart a process, and should therefore be used with care.

# set_log_type(NewType)

    -spec set_log_type(NewType) -> {ok, OldType} | {error, Reason}
                          when NewType :: snmp:atl_type(), OldType :: snmp:atl_type(), Reason :: term().

Changes the run-time Audit Trail log type.

Note that this has no effect on the application configuration as defined by configuration files, so a node restart will revert the config to whatever is in those files.

This function is primarily useful in testing/debugging scenarios.

# sync_get2(UserId, TargetName, Oids)

(since OTP R14B03)

    -spec sync_get2(UserId, TargetName, Oids) -> {ok, SnmpReply, Remaining} | {error, Reason}
                       when
                           UserId :: user_id(),
                           TargetName :: target_name(),
                           Oids :: [snmp:oid()],
                           SnmpReply :: snmp_reply(),
                           Remaining :: non_neg_integer(),
                           Reason ::
                               {send_failed, ReqId, ActualReason} |
                               {invalid_sec_info, SecInfo, SnmpInfo} |
                               term(),
                           ReqId :: request_id(),
                           ActualReason :: term(),
                           SecInfo :: {SecTag, ExpectedValue, ReceivedValue},
                           SecTag :: atom(),
                           ExpectedValue :: term(),
                           ReceivedValue :: term(),
                           SnmpInfo :: term().

Equivalent to `sync_get2/4`.

# sync_get2(UserId, TargetName, Oids, SendOpts)

(since OTP R14B03)

    -spec sync_get2(UserId, TargetName, Oids, SendOpts) -> {ok, SnmpReply, Remaining} | {error, Reason}
                       when
                           UserId :: user_id(),
                           TargetName :: target_name(),
                           Oids :: [snmp:oid()],
                           SendOpts :: [SendOpt],
                           SendOpt ::
                               {context, snmp:context_name()} |
                               {timeout, pos_integer()} |
                               {community, snmp:community()} |
                               {sec_model, snmp:sec_model()} |
                               {sec_name, snmp:sec_name()} |
                               {sec_level, snmp:sec_level()} |
                               {max_message_size, snmp:mms()} |
                               {extra, term()},
                           SnmpReply :: snmp_reply(),
                           Remaining :: non_neg_integer(),
                           Reason ::
                               {send_failed, ReqId, ActualReason} |
                               {invalid_sec_info, SecInfo, SnmpInfo} |
                               term(),
                           ReqId :: request_id(),
                           ActualReason :: term(),
                           SecInfo :: {SecTag, ExpectedValue, ReceivedValue},
                           SecTag :: atom(),
                           ExpectedValue :: term(),
                           ReceivedValue :: term(),
                           SnmpInfo :: term().

Synchronous `get-request`.

`Remaining` is the remaining time of the given (or default) timeout time.

When Reason is {send_failed, ...} it means that the `net-if` process failed to send the (`get-request` ) message. This could happen because of any number of reasons, i.e. encoding error. ActualReason is the actual reason in this case.

The send option `extra` specifies an opaque data structure passed on to the `net-if` process. The `net-if` process included in this application makes, with one exception, no use of this info, so the only use for it (when using the built in `net-if`) would be tracing. The one usage exception is: Any tuple with `snmpm_extra_info_tag` as its first element is reserved for internal use.

Some of the send options (`community`, `sec_model`, `sec_name`, `sec_level` and `max_message_size`) are `override options`. That is, for this request, they override any configuration done when the agent was registered.

For `SnmpInfo`, see the user callback function handle_report.

# sync_get_bulk2(UserId, TargetName, NonRep, MaxRep, Oids)

(since OTP R14B03)

    -spec sync_get_bulk2(UserId, TargetName, NonRep, MaxRep, Oids) ->
                            {ok, SnmpReply, Remaining} | {error, Reason}
                            when
                                UserId :: user_id(),
                                TargetName :: target_name(),
                                NonRep :: non_neg_integer(),
                                MaxRep :: non_neg_integer(),
                                Oids :: [snmp:oid()],
                                SnmpReply :: snmp_reply(),
                                Remaining :: non_neg_integer(),
                                Reason ::
                                    {send_failed, ReqId, ActualReason} |
                                    {invalid_sec_info, SecInfo, SnmpInfo} |
                                    term(),
                                ReqId :: request_id(),
                                ActualReason :: term(),
                                SecInfo :: {SecTag, ExpectedValue, ReceivedValue},
                                SecTag :: atom(),
                                ExpectedValue :: term(),
                                ReceivedValue :: term(),
                                SnmpInfo :: term().

Equivalent to `sync_get_bulk2/6`.

# sync_get_bulk2(UserId, TargetName, NonRep, MaxRep, Oids, SendOpts)

(since OTP R14B03)

    -spec sync_get_bulk2(UserId, TargetName, NonRep, MaxRep, Oids, SendOpts) ->
                            {ok, SnmpReply, Remaining} | {error, Reason}
                            when
                                UserId :: user_id(),
                                TargetName :: target_name(),
                                NonRep :: non_neg_integer(),
                                MaxRep :: non_neg_integer(),
                                Oids :: [snmp:oid()],
                                SendOpts :: [SendOpt],
                                SendOpt ::
                                    {context, snmp:context_name()} |
                                    {timeout, pos_integer()} |
                                    {community, snmp:community()} |
                                    {sec_model, snmp:sec_model()} |
                                    {sec_name, snmp:sec_name()} |
                                    {sec_level, snmp:sec_level()} |
                                    {max_message_size, snmp:mms()} |
                                    {extra, term()},
                                ReqId :: request_id(),
                                SnmpReply :: snmp_reply(),
                                Remaining :: non_neg_integer(),
                                Reason ::
                                    {send_failed, ReqId, ActualReason} |
                                    {invalid_sec_info, SecInfo, SnmpInfo} |
                                    term(),
                                ReqId :: request_id(),
                                ActualReason :: term(),
                                SecInfo :: {SecTag, ExpectedValue, ReceivedValue},
                                SecTag :: atom(),
                                ExpectedValue :: term(),
                                ReceivedValue :: term(),
                                SnmpInfo :: term().

Synchronous `get-bulk-request` (See RFC1905).

`Remaining` is the remaining time of the given (or default) timeout time.

When Reason is {send_failed, ...} it means that the `net-if` process failed to send the message. This could happen because of any number of reasons, i.e. encoding error. ActualReason is the actual reason in this case.

The send option `extra` specifies an opaque data structure passed on to the `net-if` process. The `net-if` process included in this application makes, with one exception, no use of this info, so the only use for it (when using the built in `net-if`) would be tracing. The one usage exception is: Any tuple with `snmpm_extra_info_tag` as its first element is reserved for internal use.

Some of the send options (`community`, `sec_model`, `sec_name`, `sec_level` and `max_message_size`) are `override options`. That is, for this request, they override any configuration done when the agent was registered.

For `SnmpInfo`, see the user callback function `snmpm_user:handle_report/3`.

# sync_get_next2(UserId, TargetName, Oids)

(since OTP R14B03)

    -spec sync_get_next2(UserId, TargetName, Oids) -> {ok, SnmpReply, Remaining} | {error, Reason}
                            when
                                UserId :: user_id(),
                                TargetName :: target_name(),
                                Oids :: [snmp:oid()],
                                SnmpReply :: snmp_reply(),
                                Remaining :: non_neg_integer(),
                                Reason ::
                                    {send_failed, ReqId, ActualReason} |
                                    {invalid_sec_info, SecInfo, SnmpInfo} |
                                    term(),
                                ReqId :: request_id(),
                                ActualReason :: term(),
                                SecInfo :: {SecTag, ExpectedValue, ReceivedValue},
                                SecTag :: atom(),
                                ExpectedValue :: term(),
                                ReceivedValue :: term(),
                                SnmpInfo :: term().

Equivalent to `sync_get_next2/4`.

# sync_get_next2(UserId, TargetName, Oids, SendOpts)

(since OTP R14B03)

    -spec sync_get_next2(UserId, TargetName, Oids, SendOpts) -> {ok, SnmpReply, Remaining} | {error, Reason}
                            when
                                UserId :: user_id(),
                                TargetName :: target_name(),
                                Oids :: [snmp:oid()],
                                SendOpts :: [SendOpt],
                                SendOpt ::
                                    {context, snmp:context_name()} |
                                    {timeout, pos_integer()} |
                                    {community, snmp:community()} |
                                    {sec_model, snmp:sec_model()} |
                                    {sec_name, snmp:sec_name()} |
                                    {sec_level, snmp:sec_level()} |
                                    {max_message_size, snmp:mms()} |
                                    {extra, term()},
                                SnmpReply :: snmp_reply(),
                                Remaining :: non_neg_integer(),
                                Reason ::
                                    {send_failed, ReqId, ActualReason} |
                                    {invalid_sec_info, SecInfo, SnmpInfo} |
                                    term(),
                                ReqId :: request_id(),
                                ActualReason :: term(),
                                SecInfo :: {SecTag, ExpectedValue, ReceivedValue},
                                SecTag :: atom(),
                                ExpectedValue :: term(),
                                ReceivedValue :: term(),
                                SnmpInfo :: term().

Synchronous `get-next-request`.

`Remaining` is the remaining time of the given (or default) timeout time.

When Reason is {send_failed, ...} it means that the `net-if` process failed to send the message. This could happen because of any number of reasons, i.e. encoding error. ActualReason is the actual reason in this case.

The send option `extra` specifies an opaque data structure passed on to the `net-if` process. The `net-if` process included in this application makes, with one exception, no use of this info, so the only use for it (when using the built in `net-if`) would be tracing. The one usage exception is: Any tuple with `snmpm_extra_info_tag` as its first element is reserved for internal use.

Some of the send options (`community`, `sec_model`, `sec_name`, `sec_level` and `max_message_size`) are `override options`. That is, for this request, they override any configuration done when the agent was registered.

For `SnmpInfo`, see the user callback function handle_report.

# sync_set2(UserId, TargetName, VarsAndVals)

(since OTP R14B03)

    -spec sync_set2(UserId, TargetName, VarsAndVals) -> {ok, SnmpReply, Remaining} | {error, Reason}
                       when
                           UserId :: user_id(),
                           TargetName :: target_name(),
                           VarsAndVals :: [var_and_val()],
                           SnmpReply :: snmp_reply(),
                           Remaining :: non_neg_integer(),
                           Reason ::
                               {send_failed, ReqId, ActualReason} |
                               {invalid_sec_info, SecInfo, SnmpInfo} |
                               term(),
                           ReqId :: request_id(),
                           ActualReason :: term(),
                           SecInfo :: {SecTag, ExpectedValue, ReceivedValue},
                           SecTag :: atom(),
                           ExpectedValue :: term(),
                           ReceivedValue :: term(),
                           SnmpInfo :: term().

Equivalent to `sync_set2/4`.

# sync_set2(UserId, TargetName, VarsAndVals, SendOpts)

(since OTP R14B03)

    -spec sync_set2(UserId, TargetName, VarsAndVals, SendOpts) ->
                       {ok, SnmpReply, Remaining} | {error, Reason}
                       when
                           UserId :: user_id(),
                           TargetName :: target_name(),
                           VarsAndVals :: [var_and_val()],
                           SendOpts :: [SendOpt],
                           SendOpt ::
                               {context, snmp:context_name()} |
                               {timeout, pos_integer()} |
                               {community, snmp:community()} |
                               {sec_model, snmp:sec_model()} |
                               {sec_name, snmp:sec_name()} |
                               {sec_level, snmp:sec_level()} |
                               {max_message_size, snmp:mms()} |
                               {extra, term()},
                           SnmpReply :: snmp_reply(),
                           Remaining :: non_neg_integer(),
                           Reason ::
                               {send_failed, ReqId, ActualReason} |
                               {invalid_sec_info, SecInfo, SnmpInfo} |
                               term(),
                           ReqId :: request_id(),
                           ActualReason :: term(),
                           SecInfo :: {SecTag, ExpectedValue, ReceivedValue},
                           SecTag :: atom(),
                           ExpectedValue :: term(),
                           ReceivedValue :: term(),
                           SnmpInfo :: term().

Synchronous `set-request`.

`Remaining` is the remaining time of the given (or default) timeout time.

When Reason is {send_failed, ...} it means that the `net-if` process failed to send the message. This could happen because of any number of reasons, i.e. encoding error. ActualReason is the actual reason in this case.

When var_and_val() is {oid(), value()}, the manager makes an educated guess based on the loaded mibs.

The send option `extra` specifies an opaque data structure passed on to the `net-if` process. The `net-if` process included in this application makes, with one exception, no use of this info, so the only use for it (when using the built in `net-if`) would be tracing. The one usage exception is: Any tuple with `snmpm_extra_info_tag` as its first element is reserved for internal use.

Some of the send options (`community`, `sec_model`, `sec_name`, `sec_level` and `max_message_size`) are `override options`. That is, for this request, they override any configuration done when the agent was registered.

For `SnmpInfo`, see the user callback function `snmpm_user:handle_report/3`.

# unload_mib(MibName)

    -spec unload_mib(MibName) -> ok | {error, Reason} when MibName :: snmp:mib_name(), Reason :: term().

Unload a `Mib` from the manager. The `MibName` is the name of the Mib, including the path to where the compiled mib is found. For example,

              Dir = code:priv_dir(my_app) ++ "/mibs/",
              snmpm:unload_mib(Dir ++ "MY-MIB").

# unregister_agent(UserId, TargetName)

    -spec unregister_agent(UserId, TargetName) -> ok | {error, Reason}
                              when UserId :: user_id(), TargetName :: target_name(), Reason :: term().

Unregister the agent.

# unregister_user(UserId)

    -spec unregister_user(UserId) -> ok | {error, Reason} when UserId :: user_id(), Reason :: term().

Unregister the user.

# unregister_usm_user(EngineID, UserName)

    -spec unregister_usm_user(EngineID, UserName) -> ok | {error, Reason}
                                 when
                                     EngineID :: snmp:engine_id(),
                                     UserName :: snmp:usm_name(),
                                     Reason :: term().

Unregister this USM user.

# update_agent_info(UserId, TargetName, Info)

(since OTP R14B04)

    -spec update_agent_info(UserId, TargetName, Info) -> ok | {error, Reason}
                               when
                                   UserId :: user_id(),
                                   TargetName :: target_name(),
                                   Info :: [{Item, Value}],
                                   Item :: agent_config_item(),
                                   Value :: term(),
                                   Reason :: term().

Update agent config.

This function, `update_agent_info/3`, should be used when several values needs to be updated atomically.

See function `register_agent/3` for more info about what kind of items are allowed.

# update_agent_info(UserId, TargetName, Item, Value)

    -spec update_agent_info(UserId, TargetName, Item, Value) -> ok | {error, Reason}
                               when
                                   UserId :: user_id(),
                                   TargetName :: target_name(),
                                   Item :: agent_config_item(),
                                   Value :: term(),
                                   Reason :: term().

Update agent config.

See function `register_agent/3` for more info about what kind of items are allowed.

# update_usm_user_info(EngineID, UserName, Item, Value)

    -spec update_usm_user_info(EngineID, UserName, Item, Value) -> ok | {error, Reason}
                                  when
                                      EngineID :: snmp:engine_id(),
                                      UserName :: snmp:usm_name(),
                                      Item :: usm_config_item(),
                                      Value :: term(),
                                      Reason :: term().

Update usm user config.

# usm_user_info(EngineID, UserName, Item)

    -spec usm_user_info(EngineID, UserName, Item) -> {ok, Value} | {error, Reason}
                           when
                               EngineID :: snmp:engine_id(),
                               UserName :: snmp:usm_name(),
                               Item :: usm_config_item(),
                               Value :: term(),
                               Reason :: term().

Retrieve usm user config.

# verbosity(Target, Verbosity)

    -spec verbosity(Target, Verbosity) -> snmp:void()
                       when
                           Target :: config | server | net_if | note_store | all,
                           Verbosity :: snmp:verbosity().

Sets verbosity for the designated process. For the lowest verbosity `silence`, nothing is printed. The higher the verbosity, the more is printed.

# which_agents()

    -spec which_agents() -> Agents when Agents :: [target_name()].

Equivalent to `which_agents/1`.

# which_agents(UserId)

    -spec which_agents(UserId) -> Agents when UserId :: user_id(), Agents :: [target_name()].

Get a list of all registered agents or all agents registered by a specific user.

# which_mibs()

    -spec which_mibs() -> Mibs
                        when Mibs :: [{MibName, MibFile}], MibName :: snmp:mib_name(), MibFile :: string().

Get a list of all the mib's loaded into the manager.

# which_users()

    -spec which_users() -> Users when Users :: [user_id()].

Get a list of the identities of all registered users.

# which_usm_users()

    -spec which_usm_users() -> UsmUsers
                             when
                                 UsmUsers :: [{EngineID, UserName}],
                                 EngineID :: snmp:engine_id(),
                                 UserName :: snmp:usm_name().

Get a list of all registered usm users.

# which_usm_users(EngineID)

    -spec which_usm_users(EngineID) -> UsmUsers
                             when
                                 EngineID :: snmp:engine_id(),
                                 UsmUsers :: [UserName],
                                 UserName :: snmp:usm_name().

Get a list of all registered usm users with engine-id `EngineID`.