[snmp/agent] Improved loading and unload of MIBs

Improved the documentation of the loading and unloading
of MIBs (plural). also added functions for loading and
unloading a single mib.

OTP-11216

10 files changed, 378 insertions, 111 deletions

diff --git a/lib/snmp/doc/src/notes.xml b/lib/snmp/doc/src/notes.xml
index 21c417f0c1..8ba2161a9d 100644
--- a/lib/snmp/doc/src/notes.xml
+++ b/lib/snmp/doc/src/notes.xml
@@ -34,6 +34,73 @@
 
 
   <section>
+    <title>SNMP Development Toolkit 4.24.2</title>
+    <p>Version 4.24.2 supports code replacement in runtime from/to
+    version 4.24.1, 4.24, 4.23.1 and 4.23. </p>
+
+    <section>
+      <title>Improvements and new features</title>
+<!--
+      <p>-</p>
+-->
+
+      <list type="bulleted">
+        <item>
+          <p>[agent] Improved documentation for the functions for 
+	  loading and unloading mibs, 
+	  see <seealso marker="snmpa#load_mibs">load_mibs</seealso> and 
+	  <seealso marker="snmpa#unload_mibs">unload_mibs</seealso> for 
+	  more info. </p>
+          <p>Also added new functions for loading and unloading a single mib, 
+	  see <seealso marker="snmpa#load_mib">load_mib</seealso> and 
+	  <seealso marker="snmpa#unload_mib">unload_mib</seealso> for 
+	  more info. </p>
+          <p>Own Id: OTP-11216</p>
+        </item>
+
+      </list>
+
+    </section>
+
+    <section>
+      <title>Fixed Bugs and Malfunctions</title>
+      <p>-</p>
+
+<!--
+      <list type="bulleted">
+        <item>
+          <p>[agent] 
+	  see <seealso marker="snmpa#load_mibs">load_mibs</seealso> and 
+	  <seealso marker="snmpa#unload_mibs">unload_mibs</seealso>. </p>
+          <p>Own Id: OTP-11216</p>
+        </item>
+
+      </list>
+-->
+
+    </section>
+
+    <section>
+      <title>Incompatibilities</title>
+      <p>-</p>
+
+<!--
+      <list type="bulleted">
+        <item>
+          <p>[manager] The old Addr-and-Port based API functions, previously
+	  long deprecated and marked for deletion in R16B, has now been
+	  removed. </p>
+          <p>Own Id: OTP-10027</p>
+        </item>
+
+      </list>
+-->
+    </section>
+
+  </section> <!-- 4.24.2 -->
+
+
+  <section>
     <title>SNMP Development Toolkit 4.24.1</title>
     <p>Version 4.24.1 supports code replacement in runtime from/to
     version 4.24, 4.23.1 and 4.23. </p>
diff --git a/lib/snmp/doc/src/snmpa.xml b/lib/snmp/doc/src/snmpa.xml
index 86fde03205..77146f3a89 100644
--- a/lib/snmp/doc/src/snmpa.xml
+++ b/lib/snmp/doc/src/snmpa.xml
@@ -245,29 +245,75 @@ notification_delivery_info() = #snmpa_notification_delivery_info{}
           This function is used to convert to the old (pre-4.4) info 
           format. </p>
 
+        <marker id="load_mib"></marker>
+      </desc>
+    </func>
+
+    <func>
+      <name>load_mib(Mib) -> ok | {error, Reason}</name>
+      <name>load_mib(Agent, Mib) -> ok | {error, Reason}</name>
+      <fsummary>Load single MIB into the agent</fsummary>
+      <type>
+        <v>Agent = pid() | atom()</v>
+        <v>MibName = string()</v>
+        <v>Reason = already_loaded | term()</v>
+      </type>
+      <desc>
+        <p>Load a single <c>Mib</c> into an agent. The <c>MibName</c> 
+	is the name of the Mib, including the path to where the compiled 
+	mib is found. For example: </p>
+	<code type="none">
+          Dir = code:priv_dir(my_app) ++ "/mibs/",
+          snmpa:load_mib(snmp_master_agent, Dir ++ "MY-MIB").
+        </code>
+
         <marker id="load_mibs"></marker>
       </desc>
     </func>
 
     <func>
       <name>load_mibs(Mibs) -> ok | {error, Reason}</name>
-      <name>load_mibs(Agent,Mibs) -> ok | {error, Reason}</name>
+      <name>load_mibs(Mibs, Force) -> ok | {error, Reason}</name>
+      <name>load_mibs(Agent, Mibs) -> ok | {error, Reason}</name>
+      <name>load_mibs(Agent, Mibs, Force) -> ok | {error, Reason}</name>
       <fsummary>Load MIBs into the agent</fsummary>
       <type>
         <v>Agent = pid() | atom()</v>
         <v>Mibs = [MibName]</v>
+        <v>Force = boolean()</v>
         <v>MibName = string()</v>
-        <v>Reason = term()</v>
+        <v>Reason = {'load aborted at', MibName, InternalReason}</v>
+        <v>InternalReason = already_loaded | term()</v>
       </type>
       <desc>
-        <p>Loads <c>Mibs</c> into an agent.  If the agent cannot load
-          all MIBs, it will indicate where loading was aborted.  The
-          <c>MibName</c> is the name of the Mib, including the path to
-          where the compiled mib is found.  For example,</p>
-        <code type="none">
+        <p>Load <c>Mibs</c> into an agent.  If the agent cannot load all 
+	MIBs (the default value of the <c>Force</c> argument is <c>false</c>), 
+	it will indicate where loading was aborted. The <c>MibName</c> 
+	is the name of the Mib, including the path to where the compiled 
+	mib is found. For example,</p>
+	<code type="none">
           Dir = code:priv_dir(my_app) ++ "/mibs/",
           snmpa:load_mibs(snmp_master_agent, [Dir ++ "MY-MIB"]).
         </code>
+	<p>If <c>Force = true</c> then the agent will continue attempting
+	to load each mib even after failing to load a previous mib. Use with 
+	care. </p>
+
+        <marker id="unload_mib"></marker>
+      </desc>
+    </func>
+
+    <func>
+      <name>unload_mib(Mib) -> ok | {error, Reason}</name>
+      <name>unload_mib(Agent, Mib) -> ok | {error, Reason}</name>
+      <fsummary>Unload single MIB from the agent</fsummary>
+      <type>
+        <v>Agent = pid() | atom()</v>
+        <v>MibName = string()</v>
+        <v>Reason = not_loaded | term()</v>
+      </type>
+      <desc>
+        <p>Unload a single <c>Mib</c> from an agent. </p>
 
         <marker id="unload_mibs"></marker>
       </desc>
@@ -275,16 +321,25 @@ notification_delivery_info() = #snmpa_notification_delivery_info{}
 
     <func>
       <name>unload_mibs(Mibs) -> ok | {error, Reason}</name>
-      <name>unload_mibs(Agent,Mibs) -> ok | {error, Reason}</name>
+      <name>unload_mibs(Mibs, Force) -> ok | {error, Reason}</name>
+      <name>unload_mibs(Agent, Mibs) -> ok | {error, Reason}</name>
+      <name>unload_mibs(Agent, Mibs, Force) -> ok | {error, Reason}</name>
       <fsummary>Unload MIBs from the agent</fsummary>
       <type>
         <v>Agent = pid() | atom()</v>
         <v>Mibs = [MibName]</v>
+        <v>Force = boolean()</v>
         <v>MibName = string()</v>
+        <v>Reason = {'unload aborted at', MibName, InternalReason}</v>
+        <v>InternalReason = not_loaded | term()</v>
       </type>
       <desc>
-        <p>Unloads MIBs into an agent.  If it cannot unload all MIBs,
-          it will indicate where unloading was aborted. </p>
+        <p>Unload <c>Mibs</c> from an agent. If it cannot unload all MIBs
+	(the default value of the <c>Force</c> argument is <c>false</c>),
+	it will indicate where unloading was aborted. </p>
+	<p>If <c>Force = true</c> then the agent will continue attempting
+	to unload each mib even after failing to unload a previous mib. 
+	Use with care. </p>
 
         <marker id="which_mibs"></marker>
       </desc>
diff --git a/lib/snmp/src/agent/snmpa.erl b/lib/snmp/src/agent/snmpa.erl
index 14b93439df..a95e41ea42 100644
--- a/lib/snmp/src/agent/snmpa.erl
+++ b/lib/snmp/src/agent/snmpa.erl
@@ -39,8 +39,10 @@
 	 enum_to_int/2, enum_to_int/3,
 
 	 info/0, info/1, old_info_format/1, 
-	 load_mibs/1, load_mibs/2, 
-	 unload_mibs/1, unload_mibs/2, 
+	 load_mib/1, load_mib/2, 
+	 load_mibs/1, load_mibs/2, load_mibs/3, 
+	 unload_mib/1, unload_mib/2, 
+	 unload_mibs/1, unload_mibs/2, unload_mibs/3, 
 	 which_mibs/0, which_mibs/1, 
 	 whereis_mib/1, whereis_mib/2, 
 	 dump_mibs/0, dump_mibs/1,
@@ -300,19 +302,75 @@ backup(Agent, BackupDir) ->
 dump_mibs()     -> snmpa_agent:dump_mibs(snmp_master_agent).
 dump_mibs(File) -> snmpa_agent:dump_mibs(snmp_master_agent, File).
 
+
+load_mib(Mib) ->
+    load_mib(snmp_master_agent, Mib).
+
+-spec load_mib(Agent :: pid() | atom(), Mib :: string()) ->
+    ok | {error, Reason :: already_loaded | term()}.
+
+load_mib(Agent, Mib) ->
+    case load_mibs(Agent, [Mib]) of
+	{error, {'load aborted at', Mib, Reason}} ->
+	    {error, Reason};
+	Else ->
+	    Else
+    end.
+
 load_mibs(Mibs) ->
-    load_mibs(snmp_master_agent, Mibs).
+    load_mibs(snmp_master_agent, Mibs, false).
 load_mibs(Agent, Mibs) when is_list(Mibs) -> 
-    snmpa_agent:load_mibs(Agent, Mibs).
+    snmpa_agent:load_mibs(Agent, Mibs, false);
+load_mibs(Mibs, Force) 
+  when is_list(Mibs) andalso ((Force =:= true) orelse (Force =:= false)) ->
+    load_mibs(snmp_master_agent, Mibs, Force).
+
+-spec load_mibs(Agent :: pid() | atom(), 
+		Mibs  :: [MibName :: string()], 
+		Force :: boolean()) ->
+    ok | {error, {'load aborted at', MibName :: string(), InternalReason :: already_loaded | term()}}.
+
+load_mibs(Agent, Mibs, Force) 
+  when is_list(Mibs) andalso ((Force =:= true) orelse (Force =:= false)) -> 
+    snmpa_agent:load_mibs(Agent, Mibs, Force).
+
+
+unload_mib(Mib) ->
+    unload_mib(snmp_master_agent, Mib).
+
+-spec unload_mib(Agent :: pid() | atom(), Mib :: string()) ->
+    ok | {error, Reason :: not_loaded | term()}.
+
+unload_mib(Agent, Mib) ->
+    case unload_mibs(Agent, [Mib]) of
+	{error, {'unload aborted at', Mib, Reason}} ->
+	    {error, Reason};
+	Else ->
+	    Else
+    end.
 
 unload_mibs(Mibs) ->
-    unload_mibs(snmp_master_agent, Mibs).
+    unload_mibs(snmp_master_agent, Mibs, false).
 unload_mibs(Agent, Mibs) when is_list(Mibs) -> 
-    snmpa_agent:unload_mibs(Agent, Mibs).
+    snmpa_agent:unload_mibs(Agent, Mibs);
+unload_mibs(Mibs, Force) 
+  when is_list(Mibs) andalso ((Force =:= true) orelse (Force =:= false)) ->
+    unload_mibs(snmp_master_agent, Mibs, Force).
+
+-spec unload_mibs(Agent :: pid() | atom(), 
+		  Mibs  :: [MibName :: string()], 
+		  Force :: boolean()) ->
+    ok | {error, {'unload aborted at', MibName :: string(), InternalReason :: not_loaded | term()}}.
+
+unload_mibs(Agent, Mibs, Force) 
+  when is_list(Mibs) andalso ((Force =:= true) orelse (Force =:= false)) ->
+    snmpa_agent:unload_mibs(Agent, Mibs, Force).
+
 
 which_mibs()      -> which_mibs(snmp_master_agent).
 which_mibs(Agent) -> snmpa_agent:which_mibs(Agent).
 
+
 whereis_mib(Mib) ->
     whereis_mib(snmp_master_agent, Mib).
 whereis_mib(Agent, Mib) when is_atom(Mib) ->
diff --git a/lib/snmp/src/agent/snmpa_agent.erl b/lib/snmp/src/agent/snmpa_agent.erl
index c267ce5a70..9bed6e554e 100644
--- a/lib/snmp/src/agent/snmpa_agent.erl
+++ b/lib/snmp/src/agent/snmpa_agent.erl
@@ -28,7 +28,8 @@
 %% External exports
 -export([start_link/4, start_link/5, stop/1]).
 -export([subagent_set/2, 
-	 load_mibs/2, unload_mibs/2, which_mibs/1, whereis_mib/2, info/1,
+	 load_mibs/3, unload_mibs/3, 
+	 which_mibs/1, whereis_mib/2, info/1,
 	 register_subagent/3, unregister_subagent/2,
 	 send_notification/3, 
          register_notification_filter/5,
@@ -71,7 +72,8 @@
 	 handle_pdu/8, worker/2, worker_loop/1, 
 	 do_send_trap/7, do_send_trap/8]).
 %% <BACKWARD-COMPAT>
--export([handle_pdu/7]).
+-export([handle_pdu/7, 
+	 load_mibs/2, unload_mibs/2]).
 %% </BACKWARD-COMPAT>
 
 -include("snmpa_internal.hrl").
@@ -528,12 +530,22 @@ subagent_set(SubAgent, Arguments) ->
 
 
 %% Called by administrator (not agent; deadlock would occur)
+%% <BACKWARD-COMPAT>
 load_mibs(Agent, Mibs) ->
-    call(Agent, {load_mibs, Mibs}).
+    load_mibs(Agent, Mibs, false).
+%% </BACKWARD-COMPAT>
+
+load_mibs(Agent, Mibs, Force) ->
+    call(Agent, {load_mibs, Mibs, Force}).
 
 %% Called by administrator (not agent; deadlock would occur)
+%% <BACKWARD-COMPAT>
 unload_mibs(Agent, Mibs) ->
-    call(Agent, {unload_mibs, Mibs}).
+    unload_mibs(Agent, Mibs, false).
+%% </BACKWARD-COMPAT>
+
+unload_mibs(Agent, Mibs, Force) ->
+    call(Agent, {unload_mibs, Mibs, Force}).
 
 which_mibs(Agent) ->
     call(Agent, which_mibs).
@@ -1216,13 +1228,25 @@ handle_call({unregister_subagent, SubTreeOid}, _From, S) ->
 	end,
     {reply, Reply, S};
 
+%% <BACKWARD-COMPAT>
 handle_call({load_mibs, Mibs}, _From, S) ->
     ?vlog("load mibs ~p", [Mibs]),
     {reply, snmpa_mib:load_mibs(get(mibserver), Mibs), S};
+%% </BACKWARD-COMPAT>
+
+handle_call({load_mibs, Mibs, Force}, _From, S) ->
+    ?vlog("[~w] load mibs ~p", [Force, Mibs]),
+    {reply, snmpa_mib:load_mibs(get(mibserver), Mibs, Force), S};
 
+%% <BACKWARD-COMPAT>
 handle_call({unload_mibs, Mibs}, _From, S) ->
     ?vlog("unload mibs ~p", [Mibs]),
     {reply, snmpa_mib:unload_mibs(get(mibserver), Mibs), S};
+%% </BACKWARD-COMPAT>
+
+handle_call({unload_mibs, Mibs, Force}, _From, S) ->
+    ?vlog("[~w] unload mibs ~p", [Force, Mibs]),
+    {reply, snmpa_mib:unload_mibs(get(mibserver), Mibs, Force), S};
 
 handle_call(which_mibs, _From, S) ->
     ?vlog("which mibs", []),
diff --git a/lib/snmp/src/agent/snmpa_mib.erl b/lib/snmp/src/agent/snmpa_mib.erl
index 031309b990..5b523447c5 100644
--- a/lib/snmp/src/agent/snmpa_mib.erl
+++ b/lib/snmp/src/agent/snmpa_mib.erl
@@ -26,7 +26,7 @@
 %% External exports
 -export([start_link/3, stop/1, 
 	 lookup/2, next/3, which_mib/2, which_mibs/1, whereis_mib/2, 
-	 load_mibs/2, unload_mibs/2, 
+	 load_mibs/3, unload_mibs/3, 
 	 register_subagent/3, unregister_subagent/2, info/1, info/2, 
 	 verbosity/2, dump/1, dump/2,
 	 backup/2,
@@ -39,6 +39,10 @@
 	 which_cache_size/1
 	]).
 
+%% <BACKWARD-COMPAT>
+-export([load_mibs/2, unload_mibs/2]).
+%% </BACKWARD-COMPAT>
+
 %% Internal exports
 -export([init/1, handle_call/3, handle_cast/2, handle_info/2, terminate/2,
 	 code_change/3]).
@@ -182,19 +186,32 @@ next(MibServer, Oid, MibView) ->
 %%----------------------------------------------------------------------
 %% Purpose: Loads mibs into the mib process.
 %% Args: Mibs is a list of Filenames (compiled mibs).
+%%       Force is a boolean
 %% Returns: ok | {error, Reason}
 %%----------------------------------------------------------------------
+
+%% <BACKWARD-COMPAT>
 load_mibs(MibServer, Mibs) ->
-    call(MibServer, {load_mibs, Mibs}).
+    load_mibs(MibServer, Mibs, false).
+%% </BACKWARD-COMPAT>
+
+load_mibs(MibServer, Mibs, Force) ->
+    call(MibServer, {load_mibs, Mibs, Force}).
 
 
 %%----------------------------------------------------------------------
 %% Purpose: Loads mibs into the mib process.
 %% Args: Mibs is a list of Filenames (compiled mibs).
+%%       Force is a boolean
 %% Returns: ok | {error, Reason}
 %%----------------------------------------------------------------------
+%% <BACKWARD-COMPAT>
 unload_mibs(MibServer, Mibs) ->
-    call(MibServer, {unload_mibs, Mibs}).
+    unload_mibs(MibServer, Mibs, false).
+%% </BACKWARD-COMPAT>
+
+unload_mibs(MibServer, Mibs, Force) ->
+    call(MibServer, {unload_mibs, Mibs, Force}).
 
 
 %%----------------------------------------------------------------------
@@ -323,10 +340,6 @@ do_init(Prio, Mibs, Opts) ->
 %% Returns: {ok, NewMibData} | {'aborted at', Mib, NewData, Reason}
 %% Args: Operation is load_mib | unload_mib.
 %%----------------------------------------------------------------------
-mib_operations(Mod, Operation, Mibs, Data, MeOverride, TeOverride) ->
-    mib_operations(Mod, Operation, Mibs, Data, MeOverride, TeOverride, false). 
-
-
 mib_operations(_Mod, _Operation, [], Data, _MeOverride, _TeOverride, _Force) ->
     {ok, Data};
 mib_operations(Mod, Operation, [Mib|Mibs], Data0, MeOverride, TeOverride, Force) ->
@@ -451,18 +464,23 @@ handle_call({next, Oid, MibView}, _From,
     ?vdebug("next -> Reply: ~p", [Reply]), 
     {reply, Reply, NewState};
 
-handle_call({load_mibs, Mibs}, _From, 
+%% <BACKWARD-COMPAT>
+handle_call({load_mibs, Mibs}, From, State) ->
+    handle_call({load_mibs, Mibs, false}, From, State);
+%% </BACKWARD-COMPAT>
+
+handle_call({load_mibs, Mibs, Force}, _From, 
 	    #state{data         = Data, 
 		   teo          = TeOverride, 
 		   meo          = MeOverride,
 		   cache        = Cache, 
 		   data_mod     = Mod} = State) ->
-    ?vlog("load mibs ~p",[Mibs]),    
+    ?vlog("[~w] load mibs ~p", [Force, Mibs]),    
     %% Invalidate cache
     NewCache = maybe_invalidate_cache(Cache),
     {NData, Reply} = 
 	case (catch mib_operations(Mod, load_mib, Mibs, Data,
-				   MeOverride, TeOverride)) of
+				   MeOverride, TeOverride, Force)) of
 	    {'aborted at', Mib, NewData, Reason} ->
 		?vlog("aborted at ~p for reason ~p",[Mib,Reason]),    
 		{NewData, {error, {'load aborted at', Mib, Reason}}};
@@ -472,19 +490,24 @@ handle_call({load_mibs, Mibs}, _From,
     Mod:sync(NData),
     {reply, Reply, State#state{data = NData, cache = NewCache}};
 
-handle_call({unload_mibs, Mibs}, _From, 
+%% <BACKWARD-COMPAT>
+handle_call({unload_mibs, Mibs}, From, State) ->
+    handle_call({unload_mibs, Mibs, false}, From, State);
+%% </BACKWARD-COMPAT>
+
+handle_call({unload_mibs, Mibs, Force}, _From, 
 	    #state{data         = Data, 
 		   teo          = TeOverride, 
 		   meo          = MeOverride,
 		   cache        = Cache, 
 		   data_mod     = Mod} = State) ->
-    ?vlog("unload mibs ~p",[Mibs]),    
+    ?vlog("[~w] unload mibs ~p", [Force, Mibs]),    
     %% Invalidate cache
     NewCache = maybe_invalidate_cache(Cache),
     %% Unload mib(s)
     {NData, Reply} = 
 	case (catch mib_operations(Mod, unload_mib, Mibs, Data,
-				   MeOverride, TeOverride)) of
+				   MeOverride, TeOverride, Force)) of
 	    {'aborted at', Mib, NewData, Reason} ->
 		?vlog("aborted at ~p for reason ~p", [Mib,Reason]),    
 		{NewData, {error, {'unload aborted at', Mib, Reason}}};
diff --git a/lib/snmp/src/app/snmp.appup.src b/lib/snmp/src/app/snmp.appup.src
index 16b626111b..6edcf7e833 100644
--- a/lib/snmp/src/app/snmp.appup.src
+++ b/lib/snmp/src/app/snmp.appup.src
@@ -29,12 +29,22 @@
 %% {add_module,  snmpm_net_if_mt}
 
  [
+  {"4.24.1", 
+   [
+    {load_module, snmpa, soft_purge, soft_purge, [snmpa_agent]}, 
+    {update, snmpa_agent, soft, soft_purge, soft_purge, [snmpa_agent]}, 
+    {update, snmpa_mib,   soft, soft_purge, soft_purge, []}
+   ]
+  }, 
   {"4.24", 
    [
     {load_module, snmp_conf,               soft_purge, soft_purge, []}, 
     {load_module, snmp_view_based_acm_mib, soft_purge, soft_purge, 
      [snmp_conf]}, 
-    {update, snmpa_local_db, soft, soft_purge, soft_purge, []}
+    {load_module, snmpa, soft_purge, soft_purge, [snmpa_agent]}, 
+    {update, snmpa_local_db, soft, soft_purge, soft_purge, []}, 
+    {update, snmpa_agent, soft, soft_purge, soft_purge, [snmpa_agent]}, 
+    {update, snmpa_mib,   soft, soft_purge, soft_purge, []}
    ]
   }, 
   {"4.23.1", [{restart_application, snmp}]}, 
@@ -47,12 +57,22 @@
 %% {remove, {snmpm_net_if_mt, soft_purge, soft_purge}}
 
  [
+  {"4.24.1", 
+   [
+    {load_module, snmpa, soft_purge, soft_purge, [snmpa_agent]}, 
+    {update, snmpa_agent, soft, soft_purge, soft_purge, [snmpa_agent]}, 
+    {update, snmpa_mib,   soft, soft_purge, soft_purge, []}
+   ]
+  }, 
   {"4.24", 
    [
     {load_module, snmp_conf,               soft_purge, soft_purge, []}, 
     {load_module, snmp_view_based_acm_mib, soft_purge, soft_purge, 
      [snmp_conf]}, 
-    {update, snmpa_local_db, soft, soft_purge, soft_purge, []}
+    {load_module, snmpa, soft_purge, soft_purge, [snmpa_agent]}, 
+    {update, snmpa_local_db, soft, soft_purge, soft_purge, []}, 
+    {update, snmpa_agent, soft, soft_purge, soft_purge, [snmpa_agent]}, 
+    {update, snmpa_mib,   soft, soft_purge, soft_purge, []}
    ]
   }, 
   {"4.23.1", [{restart_application, snmp}]}, 
diff --git a/lib/snmp/test/snmp_agent_mibs_test.erl b/lib/snmp/test/snmp_agent_mibs_test.erl
index 248fe7d83e..f7dae64e3f 100644
--- a/lib/snmp/test/snmp_agent_mibs_test.erl
+++ b/lib/snmp/test/snmp_agent_mibs_test.erl
@@ -238,6 +238,8 @@ start_and_stop(Config) when is_list(Config) ->
 
 load_unload(suite) -> [];
 load_unload(Config) when is_list(Config) ->
+    ?DBG("load_unload -> start", []),
+
     Prio       = normal,
     Verbosity  = log,
     MibDir     = ?config(data_dir, Config),
@@ -253,8 +255,10 @@ load_unload(Config) when is_list(Config) ->
     ?line ok = load_mibs(MibsPid, MibDir, ["Test2"]),
     ?line ok = verify_loaded_mibs(MibsPid, MibDir, ["Test2"]),
     
-    ?DBG("load_unload -> load one already loaded mib", []),
-    ?line {error, _} = load_mibs(MibsPid, MibDir, ["Test2"]),
+    ?DBG("load_unload -> try load one *already loaded* mib", []),
+    EMib = join(MibDir, "Test2"), 
+    ?line {error, {'load aborted at', EMib, already_loaded}} = 
+	load_mibs(MibsPid, MibDir, ["Test2"]),
 
     ?DBG("load_unload -> load 2 not already loaded mibs", []),
     ?line ok = load_mibs(MibsPid, MibDir, ["TestTrap", "TestTrapv2"]),
@@ -266,7 +270,8 @@ load_unload(Config) when is_list(Config) ->
     ?line ok = verify_loaded_mibs(MibsPid, MibDir, ["TestTrap", "TestTrapv2"]),
     
     ?DBG("load_unload -> try unload two loaded mibs and one not loaded", []),
-    ?line {error, _} = unload_mibs(MibsPid, ["TestTrap","Test2","TestTrapv2"]),
+    ?line {error, {'unload aborted at', "Test2", not_loaded}} = 
+	   unload_mibs(MibsPid, ["TestTrap","Test2","TestTrapv2"]),
     ?line ok = verify_loaded_mibs(MibsPid, MibDir, ["TestTrapv2"]),
     
     ?DBG("load_unload -> unload the remaining loaded mib", []),
@@ -279,6 +284,7 @@ load_unload(Config) when is_list(Config) ->
     ?DBG("load_unload -> stop symbolic store", []),
     ?line sym_stop(),
 
+    ?DBG("load_unload -> done", []),
     ok.
 
 
@@ -691,10 +697,16 @@ mibs_info(Pid) ->
 
 load_mibs(Pid, Dir, Mibs0) ->
     Mibs = [join(Dir, Mib) || Mib <- Mibs0],
-    snmpa_mib:load_mibs(Pid, Mibs).
+    Res = snmpa_mib:load_mibs(Pid, Mibs),
+    %% ?DBG("load_mibs -> "
+    %% 	 "~n   Res: ~p", [Res]),
+    Res.
 
 unload_mibs(Pid, Mibs) ->
-    snmpa_mib:unload_mibs(Pid, Mibs).
+    Res = snmpa_mib:unload_mibs(Pid, Mibs),
+    %% ?DBG("unload_mibs -> "
+    %% 	 "~n   Res: ~p", [Res]),
+    Res.
 
 verify_loaded_mibs(Pid, Dir, ExpectedMibs0) ->
     ExpectedMibs = [join(Dir, Mib) || Mib <- ExpectedMibs0],
diff --git a/lib/snmp/test/snmp_agent_test.erl b/lib/snmp/test/snmp_agent_test.erl
index 6fe97ccd25..7e683e315a 100644
--- a/lib/snmp/test/snmp_agent_test.erl
+++ b/lib/snmp/test/snmp_agent_test.erl
@@ -554,7 +554,7 @@ init_per_suite(Config0) when is_list(Config0) ->
 
     %% Mib-dirs
     MibDir    = snmp_test_lib:lookup(data_dir, Config2),
-    StdMibDir = filename:join([code:priv_dir(snmp), "mibs"]),
+    StdMibDir = join([code:priv_dir(snmp), "mibs"]),
 
     Config3 = [{mib_dir, MibDir}, {std_mib_dir, StdMibDir} | Config2],
 
@@ -748,21 +748,21 @@ init_per_testcase2(Case, Config) ->
     CaseTopDir = snmp_test_lib:init_testcase_top_dir(Case, Config), 
 
     %% Create agent top-dir(s)
-    AgentTopDir = filename:join([CaseTopDir, agent]),
+    AgentTopDir = join([CaseTopDir, agent]),
     ok = file:make_dir(AgentTopDir),
-    AgentConfDir = filename:join([AgentTopDir, config]),
+    AgentConfDir = join([AgentTopDir, config]),
     ok = file:make_dir(AgentConfDir),
-    AgentDbDir = filename:join([AgentTopDir, db]),
+    AgentDbDir = join([AgentTopDir, db]),
     ok = file:make_dir(AgentDbDir),
-    AgentLogDir = filename:join([AgentTopDir, log]),
+    AgentLogDir = join([AgentTopDir, log]),
     ok = file:make_dir(AgentLogDir),
 
     %% Create sub-agent top-dir(s)
-    SubAgentTopDir = filename:join([CaseTopDir, sub_agent]),
+    SubAgentTopDir = join([CaseTopDir, sub_agent]),
     ok = file:make_dir(SubAgentTopDir),
 
     %% Create manager top-dir(s)
-    ManagerTopDir = filename:join([CaseTopDir, manager]),
+    ManagerTopDir = join([CaseTopDir, manager]),
     ok = file:make_dir(ManagerTopDir),
 
     [{case_top_dir,      CaseTopDir}, 
@@ -1738,19 +1738,19 @@ init_case(Config) ->
 load_master(Mib) ->
     ?DBG("load_master -> entry with"
 	"~n   Mib: ~p", [Mib]),
-    snmpa:unload_mibs(snmp_master_agent, [Mib]),	% Unload for safety
-    ok = snmpa:load_mibs(snmp_master_agent, [get(mib_dir) ++ Mib]).
+    snmpa:unload_mib(snmp_master_agent, Mib),	% Unload for safety
+    ok = snmpa:load_mib(snmp_master_agent, join(get(mib_dir), Mib)).
 
 load_master_std(Mib) ->
     ?DBG("load_master_std -> entry with"
 	"~n   Mib: ~p", [Mib]),
-    snmpa:unload_mibs(snmp_master_agent, [Mib]),	% Unload for safety
-    ok = snmpa:load_mibs(snmp_master_agent, [get(std_mib_dir) ++ Mib]).
+    snmpa:unload_mib(snmp_master_agent, Mib),	% Unload for safety
+    ok = snmpa:load_mib(snmp_master_agent, join(get(std_mib_dir), Mib)).
 
 unload_master(Mib) ->
     ?DBG("unload_master -> entry with"
 	"~n   Mib: ~p", [Mib]),
-    ok = snmpa:unload_mibs(snmp_master_agent, [Mib]).
+    ok = snmpa:unload_mib(snmp_master_agent, Mib).
 
 loaded_mibs() ->
     ?DBG("loaded_mibs -> entry",[]),
@@ -2155,11 +2155,11 @@ subagent(Config) when is_list(Config) ->
     try_test(unreg_test),
 
     ?P1("Loading previous subagent mib in master and testing..."),
-    ?line ok = snmpa:load_mibs(MA, [MibDir ++ "Klas1"]),
+    ?line ok = snmpa:load_mib(MA, join(MibDir, "Klas1")),
     try_test(load_test),
 
     ?P1("Unloading previous subagent mib in master and testing..."),
-    ?line ok = snmpa:unload_mibs(MA, [MibDir ++ "Klas1"]),
+    ?line ok = snmpa:unload_mib(MA, join(MibDir, "Klas1")),
     try_test(unreg_test),
     ?P1("Testing register subagent..."),
     rpc:call(SaNode, snmp, register_subagent,
@@ -2355,11 +2355,11 @@ sa_register(Config) when is_list(Config) ->
 
     ?P1("Unloading Klas1..."),
     ?DBG("sa_register -> unload mibs", []),
-    snmpa:unload_mibs(SA, [MibDir ++ "Klas1"]),
+    snmpa:unload_mib(SA, join(MibDir, "Klas1")),
 
     ?P1("Loading SA-MIB..."),
     ?DBG("sa_register -> unload mibs", []),
-    snmpa:load_mibs(SA, [MibDir ++ "SA-MIB"]),
+    snmpa:load_mib(SA, join(MibDir, "SA-MIB")),
     
     ?P1("register subagent..."),
     ?DBG("sa_register -> register subagent", []),
@@ -2578,7 +2578,7 @@ next_across_sa(Config) when is_list(Config) ->
     ?line {ok, SA} = start_subagent(SaNode, ?sa, "SA-MIB"),
 
     ?P1("Loading another subagent mib (Klas1)..."),
-    ?line ok = snmpa:load_mibs(SA, [MibDir ++ "Klas1"]),
+    ?line ok = snmpa:load_mib(SA, MibDir ++ "Klas1"),
 
     ?P1("register subagent..."), 
     rpc:call(SaNode, snmp, register_subagent, [MA, ?klas1, SA]),
@@ -2590,7 +2590,7 @@ next_across_sa(Config) when is_list(Config) ->
     try_test(next_across_sa_test),
 
     ?P1("Unloading mib (Klas1)"),
-    snmpa:unload_mibs(SA, [MibDir ++ "Klas1"]),
+    snmpa:unload_mib(SA, join(MibDir, "Klas1")),
     rpc:call(SaNode, snmp, unregister_subagent, [MA, ?klas1]),
     try_test(unreg_test),
 
@@ -2631,25 +2631,25 @@ undo(Config) when is_list(Config) ->
     ?line {ok, SA} = start_subagent(SaNode, ?sa, "SA-MIB"),
 
     ?P1("Load Klas3 & Klas4..."),
-    ?line ok = snmpa:load_mibs(MA, [MibDir ++ "Klas3"]),
-    ?line ok = snmpa:load_mibs(MA, [MibDir ++ "Klas4"]),
+    ?line ok = snmpa:load_mib(MA, join(MibDir, "Klas3")),
+    ?line ok = snmpa:load_mib(MA, join(MibDir, "Klas4")),
 
     ?P1("Testing undo phase at master agent..."),
     try_test(undo_test),
     try_test(api_test2),
 
     ?P1("Unload Klas3..."),
-    ?line ok = snmpa:unload_mibs(MA, [MibDir ++ "Klas3"]),
+    ?line ok = snmpa:unload_mib(MA, join(MibDir, "Klas3")),
 
     ?P1("Testing bad return values from instrum. funcs..."),
     try_test(bad_return),
 
     ?P1("Unload Klas4..."),
-    ?line ok = snmpa:unload_mibs(MA, [MibDir ++ "Klas4"]),
+    ?line ok = snmpa:unload_mib(MA, join(MibDir, "Klas4")),
 
     ?P1("Testing undo phase at subagent..."),
-    ?line ok = snmpa:load_mibs(SA, [MibDir ++ "Klas3"]),
-    ?line ok = snmpa:load_mibs(SA, [MibDir ++ "Klas4"]),
+    ?line ok = snmpa:load_mib(SA, join(MibDir, "Klas3")),
+    ?line ok = snmpa:load_mib(SA, join(MibDir, "Klas4")),
     ?line ok = snmpa:register_subagent(MA, ?klas3, SA),
     ?line ok = snmpa:register_subagent(MA, ?klas4, SA),
     try_test(undo_test),
@@ -6247,8 +6247,8 @@ otp_4394_config(AgentConfDir, MgrDir, Ip0) ->
 					     "OTP-4394 test"),
     ?line case update_usm(Vsn, AgentConfDir) of
 	true ->
-	    ?line copy_file(filename:join(AgentConfDir, "usm.conf"),
-			    filename:join(MgrDir, "usm.conf")),
+	    ?line copy_file(join(AgentConfDir, "usm.conf"),
+			    join(MgrDir, "usm.conf")),
 	    ?line update_usm_mgr(Vsn, MgrDir);
 	false ->
 	    ?line ok
@@ -6407,11 +6407,11 @@ otp8395({init, Config}) when is_list(Config) ->
     %% 
 
     AgentDbDir = ?config(agent_db_dir, Config),
-    AgentMnesiaDir = filename:join([AgentDbDir, "mnesia"]),
+    AgentMnesiaDir = join([AgentDbDir, "mnesia"]),
     mnesia_init(AgentNode, AgentMnesiaDir),
 
     %% SubAgentDir = ?config(sub_agent_dir, Config),
-    %% SubAgentMnesiaDir = filename:join([SubAgentDir, "mnesia"]),
+    %% SubAgentMnesiaDir = join([SubAgentDir, "mnesia"]),
     %% mnesia_init(SubAgentNode, SubAgentMnesiaDir),
 
     %% ok = mnesia_create_schema(AgentNode, [AgentNode, SubAgentNode]), 
@@ -6541,7 +6541,7 @@ otp8395(Config) when is_list(Config) ->
     ?SLEEP(1000),
     AgentNode   = ?config(agent_node, Config),
     AgentLogDir = ?config(agent_log_dir, Config),
-    OutFile     = filename:join([AgentLogDir, "otp8395.txt"]),
+    OutFile     = join([AgentLogDir, "otp8395.txt"]),
     {ok, LogInfo} = rpc:call(AgentNode, snmpa, log_info, []),
     ?DBG("otp8395 -> LogInfo: ~p", [LogInfo]), 
 
@@ -6579,7 +6579,7 @@ otp9884({init, Config}) when is_list(Config) ->
     %% 
 
     AgentDbDir = ?config(agent_db_dir, Config),
-    AgentMnesiaDir = filename:join([AgentDbDir, "mnesia"]),
+    AgentMnesiaDir = join([AgentDbDir, "mnesia"]),
     mnesia_init(AgentNode, AgentMnesiaDir),
 
     mnesia_create_schema(AgentNode, [AgentNode]),
@@ -6609,8 +6609,8 @@ otp9884({init, Config}) when is_list(Config) ->
     ManagerConfDir = ?config(manager_top_dir, Config),
     AgentConfDir   = ?config(agent_conf_dir, Config),
     AgentTopDir    = ?config(agent_top_dir, Config),
-    AgentBkpDir1   = filename:join([AgentTopDir, backup1]),
-    AgentBkpDir2   = filename:join([AgentTopDir, backup2]),
+    AgentBkpDir1   = join([AgentTopDir, backup1]),
+    AgentBkpDir2   = join([AgentTopDir, backup2]),
     ok = file:make_dir(AgentBkpDir1),
     ok = file:make_dir(AgentBkpDir2),
     AgentBkpDirs = [AgentBkpDir1, AgentBkpDir2], 
@@ -7105,7 +7105,7 @@ display_log(Config) ->
 		{value, {_, Node}} ->
 		    LogDir  = Dir, 
 		    Mibs    = [], 
-		    OutFile = filename:join(LogDir, "snmpa_log.txt"), 
+		    OutFile = join(LogDir, "snmpa_log.txt"), 
 		    p("~n"
 		      "========================="
 		      "  < Audit Trail Log >  "
@@ -7252,6 +7252,14 @@ lists_key1search(Key, List) when is_atom(Key) ->
 %% regs() ->
 %%     lists:sort(registered()).
 
+%% ------
+
+join(Parts) ->
+    filename:join(Parts).
+
+join(Dir, File) ->
+    filename:join(Dir, File).
+
 
 %% ------
 
diff --git a/lib/snmp/test/snmp_agent_test_lib.erl b/lib/snmp/test/snmp_agent_test_lib.erl
index 7e4b713e56..122289c28e 100644
--- a/lib/snmp/test/snmp_agent_test_lib.erl
+++ b/lib/snmp/test/snmp_agent_test_lib.erl
@@ -139,31 +139,31 @@ init_all(Config) when is_list(Config) ->
     SuiteTopDir = ?config(snmp_suite_top_dir, Config),
     ?DBG("init_all -> SuiteTopDir ~p", [SuiteTopDir]),
 
-    AgentDir = filename:join(SuiteTopDir, "agent/"), 
+    AgentDir = join(SuiteTopDir, "agent/"), 
     ?line ok = file:make_dir(AgentDir),
     ?DBG("init_all -> AgentDir ~p", [AgentDir]),
 
-    AgentDbDir = filename:join(AgentDir, "db/"), 
+    AgentDbDir = join(AgentDir, "db/"), 
     ?line ok   = file:make_dir(AgentDbDir),
     ?DBG("init_all -> AgentDbDir ~p", [AgentDbDir]),
 
-    AgentLogDir = filename:join(AgentDir, "log/"), 
+    AgentLogDir = join(AgentDir, "log/"), 
     ?line ok    = file:make_dir(AgentLogDir),
     ?DBG("init_all -> AgentLogDir ~p", [AgentLogDir]),
 
-    AgentConfDir = filename:join(AgentDir, "conf/"), 
+    AgentConfDir = join(AgentDir, "conf/"), 
     ?line ok     = file:make_dir(AgentConfDir),
     ?DBG("init_all -> AgentConfDir ~p", [AgentConfDir]),
 
-    MgrDir   = filename:join(SuiteTopDir, "mgr/"), 
+    MgrDir   = join(SuiteTopDir, "mgr/"), 
     ?line ok = file:make_dir(MgrDir),
     ?DBG("init_all -> MgrDir ~p", [MgrDir]),
 
-    SaDir    = filename:join(SuiteTopDir, "sa/"), 
+    SaDir    = join(SuiteTopDir, "sa/"), 
     ?line ok = file:make_dir(SaDir),
     ?DBG("init_all -> SaDir ~p", [SaDir]),
 
-    SaDbDir  = filename:join(SaDir, "db/"), 
+    SaDbDir  = join(SaDir, "db/"), 
     ?line ok = file:make_dir(SaDbDir),
     ?DBG("init_all -> SaDbDir ~p", [SaDbDir]),
 
@@ -183,11 +183,11 @@ init_all(Config) when is_list(Config) ->
     
     ?DBG("init_all -> application mnesia: set_env dir",[]),
     ?line application_controller:set_env(mnesia, dir, 
-					 filename:join(AgentDbDir, "Mnesia1")),
+					 join(AgentDbDir, "Mnesia1")),
 
     ?DBG("init_all -> application mnesia: set_env dir on node ~p",[SaNode]),
     ?line rpc:call(SaNode, application_controller, set_env, 
-		   [mnesia, dir,  filename:join(SaDir, "Mnesia2")]),
+		   [mnesia, dir,  join(SaDir, "Mnesia2")]),
 
     ?DBG("init_all -> create mnesia schema",[]),
     ?line ok = mnesia:create_schema([SaNode, node()]),
@@ -253,7 +253,7 @@ init_case(Config) when is_list(Config) ->
     
     MibDir = ?config(mib_dir, Config),
     put(mib_dir, MibDir),
-    StdM = filename:join(code:priv_dir(snmp), "mibs") ++ "/",
+    StdM = join(code:priv_dir(snmp), "mibs") ++ "/",
     put(std_mib_dir, StdM),
 
     MgrDir = ?config(mgr_dir, Config),
@@ -341,7 +341,7 @@ run(Mod, Func, Args, Opts) ->
     Crypto = ?CRYPTO_START(),
     ?DBG("run -> Crypto: ~p", [Crypto]),
     catch snmp_test_mgr:stop(), % If we had a running mgr from a failed case
-    StdM = filename:join(code:priv_dir(snmp), "mibs") ++ "/",
+    StdM = join(code:priv_dir(snmp), "mibs") ++ "/",
     Vsn = get(vsn), 
     ?DBG("run -> config:"
 	   "~n   M:           ~p"
@@ -763,7 +763,7 @@ start_subagent(SaNode, RegTree, Mib) ->
     MA = whereis(snmp_master_agent),
     ?DBG("start_subagent -> MA: ~p", [MA]),
     MibDir = get(mib_dir),
-    Mib1   = join(MibDir,Mib),
+    Mib1   = join(MibDir, Mib),
     Mod    = snmpa_supervisor,
     Func   = start_sub_agent,
     Args   = [MA, RegTree, [Mib1]], 
@@ -800,28 +800,25 @@ mibs(StdMibDir,MibDir) ->
      join(MibDir, "Test2.bin"),
      join(MibDir, "TestTrapv2.bin")].
 
-join(D,F) ->
-    filename:join(D,F).
-
 
 %% --- various mib load/unload functions ---
 
 load_master(Mib) ->
     ?DBG("load_master -> entry with"
 	"~n   Mib: ~p", [Mib]),
-    snmpa:unload_mibs(snmp_master_agent, [Mib]),	% Unload for safety
-    ok = snmpa:load_mibs(snmp_master_agent, [get(mib_dir) ++ Mib]).
+    snmpa:unload_mib(snmp_master_agent, Mib),	% Unload for safety
+    ok = snmpa:load_mib(snmp_master_agent, join(get(mib_dir), Mib)).
 
 load_master_std(Mib) ->
     ?DBG("load_master_std -> entry with"
 	"~n   Mib: ~p", [Mib]),
-    snmpa:unload_mibs(snmp_master_agent, [Mib]),	% Unload for safety
-    ok = snmpa:load_mibs(snmp_master_agent, [get(std_mib_dir) ++ Mib]).
+    snmpa:unload_mib(snmp_master_agent, Mib),	% Unload for safety
+    ok = snmpa:load_mibs(snmp_master_agent, join(get(std_mib_dir), Mib)).
 
 unload_master(Mib) ->
     ?DBG("unload_master -> entry with"
 	"~n   Mib: ~p", [Mib]),
-    ok = snmpa:unload_mibs(snmp_master_agent, [Mib]).
+    ok = snmpa:unload_mib(snmp_master_agent, Mib).
 
 loaded_mibs() ->
     ?DBG("loaded_mibs -> entry",[]),
@@ -1383,8 +1380,8 @@ config(Vsns, MgrDir, AgentConfDir, MIp, AIp) ->
  					     "test"),
     ?line case update_usm(Vsns, AgentConfDir) of
 	      true ->
-		  ?line copy_file(filename:join(AgentConfDir, "usm.conf"),
-				  filename:join(MgrDir, "usm.conf")),
+		  ?line copy_file(join(AgentConfDir, "usm.conf"),
+				  join(MgrDir, "usm.conf")),
 		  ?line update_usm_mgr(Vsns, MgrDir);
 	      false ->
 		  ?line ok
@@ -1403,9 +1400,9 @@ delete_files(Config) ->
 delete_files(_AgentFiles, []) ->
     ok;
 delete_files(AgentDir, [DirName|DirNames]) ->
-    Dir = filename:join(AgentDir, DirName),
+    Dir = join(AgentDir, DirName),
     {ok, Files} = file:list_dir(Dir),
-    lists:foreach(fun(FName) -> file:delete(filename:join(Dir, FName)) end,
+    lists:foreach(fun(FName) -> file:delete(join(Dir, FName)) end,
 		  Files),
     delete_files(AgentDir, DirNames).
 
@@ -1481,8 +1478,8 @@ update_usm_mgr(Vsns, Dir) ->
     end.
 
 rewrite_usm_mgr(Dir, ShaKey, DesKey) -> 
-    ?line ok = file:rename(filename:join(Dir,"usm.conf"),
-			   filename:join(Dir,"usm.old")),
+    ?line ok = file:rename(join(Dir,"usm.conf"),
+			   join(Dir,"usm.old")),
     Conf = [{"agentEngine", "newUser", "newUser", zeroDotZero, 
 	     usmHMACSHAAuthProtocol, "", "", 
 	     usmDESPrivProtocol, "", "", "", ShaKey, DesKey}, 
@@ -1492,8 +1489,8 @@ rewrite_usm_mgr(Dir, ShaKey, DesKey) ->
     ok = snmp_config:write_agent_usm_config(Dir, "", Conf).
 
 reset_usm_mgr(Dir) ->
-    ?line ok = file:rename(filename:join(Dir,"usm.old"),
-			   filename:join(Dir,"usm.conf")).
+    ?line ok = file:rename(join(Dir,"usm.old"),
+			   join(Dir,"usm.conf")).
 
 
 update_community([v3], _Dir) -> 
@@ -1526,7 +1523,7 @@ write_target_addr_conf(Dir, ManagerIp, UDP, Vsns) ->
 rewrite_target_addr_conf(Dir, NewPort) -> 
     ?DBG("rewrite_target_addr_conf -> entry with"
 	 "~n   NewPort: ~p", [NewPort]),
-    TAFile = filename:join(Dir, "target_addr.conf"),
+    TAFile = join(Dir, "target_addr.conf"),
     case file:read_file_info(TAFile) of
 	{ok, _} -> 
 	    ok;
@@ -1546,8 +1543,8 @@ rewrite_target_addr_conf(Dir, NewPort) ->
     
     ?DBG("rewrite_target_addr_conf -> NewAddrs: ~p",[NewAddrs]),
 
-    ?line ok = file:rename(filename:join(Dir,"target_addr.conf"),
-			   filename:join(Dir,"target_addr.old")),
+    ?line ok = file:rename(join(Dir,"target_addr.conf"),
+			   join(Dir,"target_addr.old")),
 
     ?line ok = snmp_config:write_agent_target_addr_config(Dir, "", NewAddrs).
 
@@ -1565,8 +1562,8 @@ rewrite_target_addr_conf2(_NewPort,O) ->
     O.
 
 reset_target_addr_conf(Dir) ->
-    ?line ok = file:rename(filename:join(Dir, "target_addr.old"),
-			   filename:join(Dir, "target_addr.conf")).
+    ?line ok = file:rename(join(Dir, "target_addr.old"),
+			   join(Dir, "target_addr.conf")).
 
 write_target_params_conf(Dir, Vsns) -> 
     F = fun(v1) -> {"target_v1", v1,  v1,  "all-rights", noAuthNoPriv};
@@ -1578,14 +1575,14 @@ write_target_params_conf(Dir, Vsns) ->
 
 rewrite_target_params_conf(Dir, SecName, SecLevel) 
   when is_list(SecName) andalso is_atom(SecLevel) -> 
-    ?line ok = file:rename(filename:join(Dir,"target_params.conf"),
-			   filename:join(Dir,"target_params.old")),
+    ?line ok = file:rename(join(Dir,"target_params.conf"),
+			   join(Dir,"target_params.old")),
     Conf = [{"target_v3", v3, usm, SecName, SecLevel}],
     snmp_config:write_agent_target_params_config(Dir, "", Conf).
 
 reset_target_params_conf(Dir) ->
-    ?line ok = file:rename(filename:join(Dir,"target_params.old"),
-			   filename:join(Dir,"target_params.conf")).
+    ?line ok = file:rename(join(Dir,"target_params.old"),
+			   join(Dir,"target_params.conf")).
 
 write_notify_conf(Dir) -> 
     Conf = [{"standard trap",   "std_trap",   trap}, 
@@ -1648,6 +1645,9 @@ rpc(Node, F, A) ->
     rpc:call(Node, snmpa, F, A).
 
 
+join(Dir, File) ->
+    filename:join(Dir, File).
+
 %% await_pdu(To) ->
 %%     await_response(To, pdu).
 %% 
diff --git a/lib/snmp/vsn.mk b/lib/snmp/vsn.mk
index e987649e11..2164121e86 100644
--- a/lib/snmp/vsn.mk
+++ b/lib/snmp/vsn.mk
@@ -18,6 +18,6 @@
 # %CopyrightEnd%
 
 APPLICATION = snmp
-SNMP_VSN    = 4.24.1
+SNMP_VSN    = 4.24.2
 PRE_VSN     =
 APP_VSN     = "$(APPLICATION)-$(SNMP_VSN)$(PRE_VSN)"