Merge branch 'hb/unmatched_returns/OTP-10908'

* hb/unmatched_returns/OTP-10908:
  Fix unmatched_returns warnings in Kernel
  Fix a minor bug in ets:tabfile_info() and ets:file2tab()
  Fix unmatched_returns warning in Kernel
  Fix unmatched_return warnings in sasl
  Fix unmatched_return warnings in kernel
  Fix unmatched_return warning in erl_prim_loader
  Fix unmatched_return warnings in stdlib
  Fix unmatched_returns warnings in STDLIB and Kernel

44 files changed, 402 insertions, 298 deletions

diff --git a/lib/kernel/src/application_controller.erl b/lib/kernel/src/application_controller.erl
index 9ed2c7a7d9..1a4473593a 100644
--- a/lib/kernel/src/application_controller.erl
+++ b/lib/kernel/src/application_controller.erl
@@ -488,7 +488,7 @@ init(Init, Kernel) ->
 	    %% called during start-up of any app.
 	    case check_conf_data(ConfData) of
 		ok ->
-		    ets:new(ac_tab, [set, public, named_table]),
+		    _ = ets:new(ac_tab, [set, public, named_table]),
 		    S = #state{conf_data = ConfData},
 		    {ok, KAppl} = make_appl(Kernel),
 		    case catch load(S, KAppl) of
@@ -1949,10 +1949,10 @@ test_change_apps(Apps, Conf) ->
 test_do_change_appl([], _, _) ->
     ok;
 test_do_change_appl([A|Apps], [], [R|Res]) ->
-    do_change_appl(R, #appl{name = A}, []),
+    _ = do_change_appl(R, #appl{name = A}, []),
     test_do_change_appl(Apps, [], Res);
 test_do_change_appl([A|Apps], [C|Conf], [R|Res]) ->
-    do_change_appl(R, #appl{name = A}, C),
+    _ = do_change_appl(R, #appl{name = A}, C),
     test_do_change_appl(Apps, Conf, Res).
 
 test_make_apps([], Res) ->
diff --git a/lib/kernel/src/application_master.erl b/lib/kernel/src/application_master.erl
index 34a3efcaf2..68f78c6eb8 100644
--- a/lib/kernel/src/application_master.erl
+++ b/lib/kernel/src/application_master.erl
@@ -1,7 +1,7 @@
 %%
 %% %CopyrightBegin%
 %% 
-%% Copyright Ericsson AB 1996-2009. All Rights Reserved.
+%% Copyright Ericsson AB 1996-2013. All Rights Reserved.
 %% 
 %% The contents of this file are subject to the Erlang Public License,
 %% Version 1.1, (the "License"); you may not use this file except in
@@ -125,7 +125,7 @@ init(Parent, Starter, ApplData, Type) ->
     State = #state{appl_data = ApplData, gleader = OldGleader},
     case start_it(State, Type) of
 	{ok, Pid} ->          % apply(M,F,A) returned ok
-	    set_timer(ApplData#appl_data.maxT),
+	    ok = set_timer(ApplData#appl_data.maxT),
 	    unlink(Starter),
 	    proc_lib:init_ack(Starter, {ok,self()}),
 	    main_loop(Parent, State#state{child = Pid});
@@ -418,4 +418,6 @@ kill_all_procs_1([], _, 0) -> ok;
 kill_all_procs_1([], _, _) -> kill_all_procs().
 
 set_timer(infinity) -> ok;
-set_timer(Time) -> timer:exit_after(Time, timeout).
+set_timer(Time) ->
+    {ok, _} = timer:exit_after(Time, timeout),
+    ok.
diff --git a/lib/kernel/src/auth.erl b/lib/kernel/src/auth.erl
index 7d463103e3..eda35147d3 100644
--- a/lib/kernel/src/auth.erl
+++ b/lib/kernel/src/auth.erl
@@ -324,7 +324,7 @@ read_cookie(Name, Size) ->
 	{ok, File} ->
 	    case file:read(File, Size) of
 		{ok, List} ->
-		    file:close(File),
+		    ok = file:close(File),
 		    check_cookie(List, []);
 		{error, Reason} ->
 		    make_error(Name, Reason)
@@ -376,7 +376,7 @@ create_cookie(Name) ->
     case file:open(Name, [write, raw]) of
 	{ok, File} ->
 	    R1 = file:write(File, Cookie),
-	    file:close(File),
+	    ok = file:close(File),
 	    R2 = file:raw_write_file_info(Name, make_info(Name)),
 	    case {R1, R2} of
 		{ok, ok} ->
diff --git a/lib/kernel/src/code.erl b/lib/kernel/src/code.erl
index 03fba96d4b..0eda558ed5 100644
--- a/lib/kernel/src/code.erl
+++ b/lib/kernel/src/code.erl
@@ -364,7 +364,7 @@ load_code_server_prerequisites() ->
 	      lists,
 	      os,
 	      unicode],
-    [M = M:module_info(module) || M <- Needed],
+    _ = [M = M:module_info(module) || M <- Needed],
     ok.
 
 do_stick_dirs() ->
diff --git a/lib/kernel/src/code_server.erl b/lib/kernel/src/code_server.erl
index 5d74e8620b..9358e2201e 100644
--- a/lib/kernel/src/code_server.erl
+++ b/lib/kernel/src/code_server.erl
@@ -153,7 +153,7 @@ loop(#state{supervisor=Supervisor}=State0) ->
 	{code_call, Pid, Req} ->
 	    case handle_call(Req, {Pid, call}, State0) of
 		{reply, Res, State} ->
-		    reply(Pid, Res),
+		    _ = reply(Pid, Res),
 		    loop(State);
 		{noreply, State} ->
 		    loop(State);
@@ -1505,13 +1505,13 @@ finish_on_load_1(Mod, File, OnLoadRes, WaitingPids, Db) ->
     erlang:finish_after_on_load(Mod, Keep),
     Res = case Keep of
 	      false ->
-		  finish_on_load_report(Mod, OnLoadRes),
+		  _ = finish_on_load_report(Mod, OnLoadRes),
 		  {error,on_load_failure};
 	      true ->
 		  ets:insert(Db, {Mod,File}),
 		  {module,Mod}
 	  end,
-    [reply(Pid, Res) || Pid <- WaitingPids],
+    _ = [reply(Pid, Res) || Pid <- WaitingPids],
     ok.
 
 finish_on_load_report(_Mod, Atom) when is_atom(Atom) ->
diff --git a/lib/kernel/src/disk_log.erl b/lib/kernel/src/disk_log.erl
index c238eff12f..9a7726cfa0 100644
--- a/lib/kernel/src/disk_log.erl
+++ b/lib/kernel/src/disk_log.erl
@@ -1076,13 +1076,13 @@ log_end(S, [], [], Sync) ->
 log_end(S, Pids, Bins, Sync) ->
     case do_log(get(log), rflat(Bins)) of
 	N when is_integer(N) ->
-	    replies(Pids, ok),
+	    ok = replies(Pids, ok),
 	    S1 = (state_ok(S))#state{cnt = S#state.cnt+N},
 	    log_end_sync(S1, Sync);
         {error, {error, {full, _Name}}, N} when Pids =:= [] ->
             log_end_sync(state_ok(S#state{cnt = S#state.cnt + N}), Sync);
 	{error, Error, N} ->
-	    replies(Pids, Error),
+	    ok = replies(Pids, Error),
 	    state_err(S#state{cnt = S#state.cnt + N}, Error)
     end.
 
@@ -1091,7 +1091,7 @@ log_end_sync(S, []) ->
     S;
 log_end_sync(S, Sync) ->
     Res = do_sync(get(log)),
-    replies(Sync, Res),
+    ok = replies(Sync, Res),
     state_err(S, Res).
 
 %% Inlined.
@@ -1183,7 +1183,7 @@ do_exit(S, From, Message0, Reason) ->
 		  _ -> Message0
 	      end,
     _ = disk_log_server:close(self()),
-    replies(From, Message),
+    ok = replies(From, Message),
     ?PROFILE(ep:done()),
     exit(Reason).
 
@@ -1881,7 +1881,8 @@ replies(Pids, Reply) ->
     send_reply(Pids, M).
 
 send_reply(Pid, M) when is_pid(Pid) ->
-    Pid ! M;
+    Pid ! M,
+    ok;
 send_reply([Pid | Pids], M) ->
     Pid ! M,
     send_reply(Pids, M);
@@ -2022,7 +2023,7 @@ notify_owners(Note) ->
 
 cache_error(S, Pids) ->
     Error = S#state.cache_error,
-    replies(Pids, Error),
+    ok = replies(Pids, Error),
     state_err(S#state{cache_error = ok}, Error).
 
 state_ok(S) ->
diff --git a/lib/kernel/src/disk_log_1.erl b/lib/kernel/src/disk_log_1.erl
index 9d431bdd30..59f5cad001 100644
--- a/lib/kernel/src/disk_log_1.erl
+++ b/lib/kernel/src/disk_log_1.erl
@@ -295,12 +295,18 @@ read_chunk_ro(FdC, FileName, Pos, MaxBytes) ->
     pread(FdC, FileName, Pos + ?HEADSZ, MaxBytes).
 
 %% -> ok | throw(Error)
-close(#cache{fd = Fd, c = []}, _FileName, read_only) ->
-    file:close(Fd);
+close(#cache{fd = Fd, c = []}, FileName, read_only) ->
+    case file:close(Fd) of
+        ok -> ok;
+        Error -> file_error(FileName, Error)
+    end;
 close(#cache{fd = Fd, c = C}, FileName, read_write) ->
     {Reply, _NewFdC} = write_cache(Fd, FileName, C),
     mark(Fd, FileName, ?CLOSED),
-    file:close(Fd),
+    case file:close(Fd) of
+        ok -> ok;
+        Error -> file_error(FileName, Error)
+    end,
     if Reply =:= ok -> ok; true -> throw(Reply) end.
 
 %% Open an internal file. Head is ignored if Mode is read_only.
@@ -320,7 +326,10 @@ int_open(FName, Repair, read_write, Head) ->
 		{ok, FileHead} ->
 		    case is_head(FileHead) of
 			yes ->
-			    file:close(Fd),
+                            case file:close(Fd) of
+                                ok -> ok;
+                                Error2 -> file_error(FName, Error2)
+                            end,
 			    case open_update(FName) of
 				{ok, Fd2} ->
 				    mark(Fd2, FName, ?OPENED),
@@ -333,14 +342,14 @@ int_open(FName, Repair, read_write, Head) ->
 			yes_not_closed when Repair ->
 			    repair(Fd, FName);
 			yes_not_closed when not Repair ->
-			    file:close(Fd),
+			    _ = file:close(Fd),
 			    throw({error, {need_repair, FName}});
 			no ->
-			    file:close(Fd),
+			    _ = file:close(Fd),
 			    throw({error, {not_a_log_file, FName}})
 		    end;
 		eof ->
-		    file:close(Fd),
+		    _= file:close(Fd),
 		    throw({error, {not_a_log_file, FName}});
 		Error ->
 		    file_error_close(Fd, FName, Error)
@@ -363,11 +372,11 @@ int_open(FName, _Repair, read_only, _Head) ->
                             FdC = #cache{fd = Fd},
 			    {ok, {existed, FdC, {0, 0}, P}};
 			no ->
-			    file:close(Fd),
+			    _= file:close(Fd),
 			    throw({error, {not_a_log_file, FName}})
 		    end;
 		eof ->
-		    file:close(Fd),
+		    _ = file:close(Fd),
 		    throw({error, {not_a_log_file, FName}});
 		Error ->
 		    file_error_close(Fd, FName, Error)
@@ -398,7 +407,7 @@ int_log_head(Fd, Head) ->
 	none ->
 	    {#cache{fd = Fd}, 0, 0};
 	Error -> 
-	    file:close(Fd),
+	    _= file:close(Fd),
 	    throw(Error)
     end.
     
@@ -450,13 +459,13 @@ ext_log_head(Fd, Head) ->
 	none ->
 	    {#cache{fd = Fd}, {0, 0}};
 	Error -> 
-            file:close(Fd),
+            _= file:close(Fd),
 	    throw(Error)
     end.
     
 %% -> _Any | throw()
 mark(Fd, FileName, What) ->
-    position_close2(Fd, FileName, 4),
+    {ok, _} = position_close2(Fd, FileName, 4),
     fwrite_close2(Fd, FileName, What).
 
 %% -> {ok, Bin} | Error
@@ -560,7 +569,7 @@ scan_f2(B, FSz, Ack, No, Bad, Size, Tail) ->
     end.
 
 done_scan(In, Out, OutName, FName, RecoveredTerms, BadChars) ->
-    file:close(In),
+    _ = file:close(In),
     case catch fclose(Out, OutName) of
         ok ->
             case file:rename(OutName, FName) of
@@ -574,21 +583,21 @@ done_scan(In, Out, OutName, FName, RecoveredTerms, BadChars) ->
                             file_error(FName, Error)
                     end;
                 Error ->
-                    file:delete(OutName),
+                    _ = file:delete(OutName),
                     file_error(FName, Error)
             end;
         Error ->
-            file:delete(OutName),
+            _ = file:delete(OutName),
             throw(Error)
     end.
 
 -spec repair_err(file:io_device(), #cache{}, file:filename(),
 		 file:filename(), {'error', file:posix()}) -> no_return().
 repair_err(In, Out, OutName, ErrFileName, Error) ->
-    file:close(In),
+    _= file:close(In),
     catch fclose(Out, OutName),
     %% OutName is often the culprit, try to remove it anyway...
-    file:delete(OutName), 
+    _ = file:delete(OutName),
     file_error(ErrFileName, Error).
 
 %% Used by wrap_log_reader.
@@ -764,10 +773,10 @@ mf_int_chunk(Handle, {FileNo, Pos}, Bin, N) ->
 	{ok, {_Alloc, FdC, _HeadSize, _FileSize}} ->
 	    case chunk(FdC, FName, Pos, Bin, N) of
 		{NewFdC, eof} ->
-		    file:close(NewFdC#cache.fd),
+		    _ = file:close(NewFdC#cache.fd),
 		    mf_int_chunk(Handle, {NFileNo, 0}, [], N);
 		{NewFdC, Other} ->
-		    file:close(NewFdC#cache.fd),
+		    _ = file:close(NewFdC#cache.fd),
 		    {Handle, conv(Other, FileNo)}
 	    end
     end.
@@ -792,10 +801,10 @@ mf_int_chunk_read_only(Handle, {FileNo, Pos}, Bin, N) ->
 	{ok, {_Alloc, FdC, _HeadSize, _FileSize}} ->
 	    case do_chunk_read_only(FdC, FName, Pos, Bin, N) of
 		{NewFdC, eof} ->
-		    file:close(NewFdC#cache.fd),
+		    _ = file:close(NewFdC#cache.fd),
 		    mf_int_chunk_read_only(Handle, {NFileNo,0}, [], N);
 		{NewFdC, Other} ->
-		    file:close(NewFdC#cache.fd),
+		    _ = file:close(NewFdC#cache.fd),
 		    {Handle, conv(Other, FileNo)}
 	    end
     end.
@@ -1017,7 +1026,7 @@ ext_file_open(FName, NewFile, OldFile, OldCnt, Head, Repair, Mode) ->
 
 read_index_file(truncate, FName, MaxF) ->
     remove_files(FName, 2, MaxF),
-    file:delete(?index_file_name(FName)),
+    _ = file:delete(?index_file_name(FName)),
     {1, 0, 0, 0};
 read_index_file(_, FName, _MaxF) ->
     read_index_file(FName).
@@ -1043,7 +1052,7 @@ read_index_file(FName) ->
 		    _ErrorOrEof ->
 			{1, 0, 0, 0}
 		end,
-	    file:close(Fd),
+	    _ = file:close(Fd),
 	    R;
 	_Error ->
 	    {1, 0, 0, 0}
@@ -1096,7 +1105,7 @@ write_index_file(read_write, FName, NewFile, OldFile, OldCnt) ->
                         %% Very old format, convert to the latest format!
 			case file:read_file(FileName) of
 			    {ok, <<_CurF, Tail/binary>>} ->
-				position_close2(Fd, FileName, bof),
+				{ok, _} = position_close2(Fd, FileName, bof),
 				Bin = <<0, 0:32, ?VERSION, NewFile:32>>,
 				NewTail = to_8_bytes(Tail, [], FileName, Fd),
 				fwrite_close2(Fd, FileName, [Bin | NewTail]),
@@ -1115,7 +1124,7 @@ write_index_file(read_write, FName, NewFile, OldFile, OldCnt) ->
 		    R = file:pread(Fd, NewPos, SzSz),
 		    OldPos = Offset + (OldFile - 1)*SzSz,
 		    pwrite_close2(Fd, FileName, OldPos, OldCntBin),
-		    file:close(Fd),
+		    _ = file:close(Fd),
 		    case R of
 			{ok, <<Lost:SzSz/unit:8>>} -> Lost;
 			{ok, _} -> 
@@ -1125,7 +1134,7 @@ write_index_file(read_write, FName, NewFile, OldFile, OldCnt) ->
 		    end;
 		true -> 	
 		    pwrite_close2(Fd, FileName, NewPos, OldCntBin),
-		    file:close(Fd),
+		    _ = file:close(Fd),
 		    0
 	    end;
 	E -> 
@@ -1137,7 +1146,7 @@ to_8_bytes(<<N:32,T/binary>>, NT, FileName, Fd) ->
 to_8_bytes(B, NT, _FileName, _Fd) when byte_size(B) =:= 0 ->
     NT;
 to_8_bytes(_B, _NT, FileName, Fd) ->
-    file:close(Fd),
+    _ = file:close(Fd),
     throw({error, {invalid_index_file, FileName}}).
 
 %% -> ok | throw(FileError)
@@ -1147,7 +1156,7 @@ index_file_trunc(FName, N) ->
 	{ok, Fd} ->
 	    case file:read(Fd, 6) of
 		eof ->
-		    file:close(Fd),
+		    _ = file:close(Fd),
 		    ok;
 		{ok, <<0, 0:32, Version>>} when Version =:= ?VERSION ->
 		    truncate_index_file(Fd, FileName, 10, 8, N);
@@ -1166,10 +1175,10 @@ truncate_index_file(Fd, FileName, Offset, N, SzSz) ->
     Pos = Offset + N*SzSz,
     case Pos > file_size(FileName) of
 	true ->
-	    file:close(Fd);
+	    ok = file:close(Fd);
 	false ->
 	    truncate_at_close2(Fd, FileName, {bof, Pos}),
-	    file:close(Fd)
+	    ok = file:close(Fd)
     end,
     ok.
 	    
@@ -1412,7 +1421,8 @@ fwrite(#cache{c = []} = FdC, _FN, B, Size) ->
             ok;
         _ -> 
             put(write_cache_timer_is_running, true),
-            erlang:send_after(?TIMEOUT, self(), {self(), write_cache})
+            erlang:send_after(?TIMEOUT, self(), {self(), write_cache}),
+            ok
     end,
     {ok, FdC#cache{sz = Size, c = B}};
 fwrite(#cache{sz = Sz, c = C} = FdC, _FN, B, Size) when Sz < ?MAX ->
@@ -1511,7 +1521,7 @@ position_close2(Fd, FileName, Pos) ->
     end.
 	    
 truncate_at_close2(Fd, FileName, Pos) ->
-    position_close2(Fd, FileName, Pos),
+    {ok, _} = position_close2(Fd, FileName, Pos),
     case file:truncate(Fd) of
 	ok    -> ok;
 	Error -> file_error_close(Fd, FileName, Error)
@@ -1519,7 +1529,7 @@ truncate_at_close2(Fd, FileName, Pos) ->
 
 fclose(#cache{fd = Fd, c = C}, FileName) ->
     %% The cache is empty if the file was opened in read_only mode.
-    write_cache_close(Fd, FileName, C),
+    _ = write_cache_close(Fd, FileName, C),
     file:close(Fd).
 
 %% -> {Reply, #cache{}}; Reply = ok | Error
@@ -1549,5 +1559,5 @@ file_error(FileName, {error, Error}) ->
 -spec file_error_close(file:fd(), file:filename(), {'error', file:posix()}) -> no_return().
 
 file_error_close(Fd, FileName, {error, Error}) ->
-    file:close(Fd),
+    _ = file:close(Fd),
     throw({error, {file_error, FileName, Error}}).
diff --git a/lib/kernel/src/disk_log_server.erl b/lib/kernel/src/disk_log_server.erl
index 8894ed87e8..684ea5b5db 100644
--- a/lib/kernel/src/disk_log_server.erl
+++ b/lib/kernel/src/disk_log_server.erl
@@ -1,7 +1,7 @@
 %%
 %% %CopyrightBegin%
 %% 
-%% Copyright Ericsson AB 1997-2009. All Rights Reserved.
+%% Copyright Ericsson AB 1997-2013. All Rights Reserved.
 %% 
 %% The contents of this file are subject to the Erlang Public License,
 %% Version 1.1, (the "License"); you may not use this file except in
@@ -83,8 +83,8 @@ accessible_logs() ->
 
 init([]) ->
     process_flag(trap_exit, true),
-    ets:new(?DISK_LOG_NAME_TABLE, [named_table, set]),
-    ets:new(?DISK_LOG_PID_TABLE, [named_table, set]),
+    _ = ets:new(?DISK_LOG_NAME_TABLE, [named_table, set]),
+    _= ets:new(?DISK_LOG_PID_TABLE, [named_table, set]),
     {ok, #state{}}.
 
 handle_call({open, W, A}, From, State) ->
@@ -159,15 +159,25 @@ ensure_started() ->
 	undefined ->
 	    LogSup = {disk_log_sup, {disk_log_sup, start_link, []}, permanent,
 		      1000, supervisor, [disk_log_sup]},
-	    supervisor:start_child(kernel_safe_sup, LogSup),
+	    {ok, _} = ensure_child_started(kernel_safe_sup, LogSup),
 	    LogServer = {disk_log_server,
 			 {disk_log_server, start_link, []},
 			 permanent, 2000, worker, [disk_log_server]},
-	    supervisor:start_child(kernel_safe_sup, LogServer),
+	    {ok, _} = ensure_child_started(kernel_safe_sup, LogServer),
 	    ok;
 	_ -> ok
     end.
 
+ensure_child_started(Sup,Child) ->
+    case supervisor:start_child(Sup, Child) of
+	{ok,Pid} ->
+	    {ok,Pid};
+	{error,{already_started,Pid}} ->
+	    {ok,Pid};
+	Error ->
+	    Error
+    end.
+
 open([{Req, From} | L], State) ->
     State2 = case do_open(Req, From, State) of
                  {pending, State1} -> 
diff --git a/lib/kernel/src/dist_ac.erl b/lib/kernel/src/dist_ac.erl
index 5c62aa31e9..a4d4ae386c 100644
--- a/lib/kernel/src/dist_ac.erl
+++ b/lib/kernel/src/dist_ac.erl
@@ -1,7 +1,7 @@
 %%
 %% %CopyrightBegin%
 %% 
-%% Copyright Ericsson AB 1997-2009. All Rights Reserved.
+%% Copyright Ericsson AB 1997-2013. All Rights Reserved.
 %% 
 %% The contents of this file are subject to the Erlang Public License,
 %% Version 1.1, (the "License"); you may not use this file except in
@@ -283,7 +283,7 @@ handle_cast(init_sync, _S) ->
 	    KernelConfig ! dist_ac_took_control,
 
 	    %% we're really just interested in nodedowns.
-	    net_kernel:monitor_nodes(true),
+	    ok = net_kernel:monitor_nodes(true),
 	    
 	    {Known, NAppls, RStarted} = sync_dacs(Appls),
 
@@ -321,7 +321,7 @@ handle_call({takeover_application, AppName, RestartType}, From, S) ->
     case keysearch(AppName, #appl.name, Appls) of
 	{value, Appl} when element(1, Appl#appl.id) =:= distributed ->
 	    {distributed, Node} = Appl#appl.id,
-	    ac_takeover(req, AppName, Node, RestartType),
+	    _ = ac_takeover(req, AppName, Node, RestartType),
 	    NAppl = Appl#appl{id = takeover},
 	    NAppls = keyreplace(AppName, #appl.name, Appls, NAppl),
 	    TR = S#state.t_reqs,
@@ -341,10 +341,10 @@ handle_call({permit_application, AppName, Bool, LockId, StartInfo}, From, S) ->
 	    %% here, but we have to be backwards-compatible.
 	    case application_controller:get_loaded(AppName) of
 		{true, _} when not Bool ->
-		    ac_stop_it(AppName),
+		    _ = ac_stop_it(AppName),
 		    {reply, ok, S};
 		{true, _} when Bool ->
-		    ac_start_it(req, AppName),
+		    _ = ac_start_it(req, AppName),
 		    {reply, ok, S};
 		false ->
 		    {reply, {error, {not_loaded, AppName}}, S}
@@ -533,7 +533,7 @@ handle_info({dist_ac_app_started, Node, Name, Res}, S) ->
 			  %% Another node started appl. Update appl list.
 			  {distributed, Node}
 		  end,
-	    ac_started(req, Name, Node),
+	    _ = ac_started(req, Name, Node),
 	    NAppl = Appl#appl{id = NId},
 	    NAppls = keyreplace(Name, #appl.name, Appls, NAppl),
 	    TmpWeights = keydelete_all(Name, 1, S#state.tmp_weights),
@@ -622,7 +622,7 @@ handle_info({nodedown, Node}, S) ->
 			    true ->
 				{true, Appl#appl{id = {failover, Node}}};
 			    false -> 
-				ac_not_running(Appl#appl.name),
+				_ = ac_not_running(Appl#appl.name),
 				{true, Appl#appl{id = undefined}}
 			end;
 		   (_) ->
@@ -656,7 +656,8 @@ handle_info({dist_ac_app_loaded, Node, Name, HisNodes, Permission, HeKnowsMe},
 			    %% he's a new node connecting to us.
 			    Msg = {dist_ac_app_loaded, node(), Name,
 				   Nodes, dist_is_runnable(Appls, Name), true},
-			    {?DIST_AC, Node} ! Msg;
+			    {?DIST_AC, Node} ! Msg,
+                            ok;
 			true ->
 			    ok
 		    end,
@@ -811,29 +812,29 @@ start_appl(AppName, S, Type) ->
 start_distributed(Appl, Name, Nodes, PermittedNodes, S, Type) ->
     case find_start_node(Nodes, PermittedNodes, Name, S) of
 	{ok, Node} when Node =:= node() ->
-	    case Appl#appl.id of
-		{failover, FoNode} when Type =:= req ->
-		    ac_failover(Name, FoNode, undefined);
-		{distributed, Node2} when Type =:= req ->
-		    ac_takeover(req, Name, Node2, undefined);
-		_ when Type =:= reply ->
-		    case lists:keysearch(Name, 2, S#state.remote_started) of
-			{value, {Node3, _}} ->
-			    ac_takeover(reply, Name, Node3, undefined);
-			_ ->
-			    ac_start_it(Type, Name)
-		    end;
-		_ ->
-		    ac_start_it(Type, Name)
-	    end,
+	    _ = case Appl#appl.id of
+		    {failover, FoNode} when Type =:= req ->
+			ac_failover(Name, FoNode, undefined);
+		    {distributed, Node2} when Type =:= req ->
+			ac_takeover(req, Name, Node2, undefined);
+		    _ when Type =:= reply ->
+			case lists:keysearch(Name, 2, S#state.remote_started) of
+			    {value, {Node3, _}} ->
+				ac_takeover(reply, Name, Node3, undefined);
+			    _ ->
+				ac_start_it(Type, Name)
+			end;
+		    _ ->
+			ac_start_it(Type, Name)
+		end,
 	    {run_waiting, true};
 	{already_started, Node} ->
-	    ac_started(Type, Name, Node),
+	    _ = ac_started(Type, Name, Node),
 	    {{distributed, Node}, false};
 	{ok, Node} ->
 	    case keysearch(Name, #appl.name, S#state.appls) of
 		{value, #appl{id = {distributed, Node}}} ->
-		    ac_started(Type, Name, Node),
+		    _ = ac_started(Type, Name, Node),
 		    {{distributed, Node}, false};
 		_ ->
 		    wait_dist_start(Node, Appl, Name, Nodes,
@@ -842,7 +843,7 @@ start_distributed(Appl, Name, Nodes, PermittedNodes, S, Type) ->
 	not_started ->
 	    wait_dist_start2(Appl, Name, Nodes, PermittedNodes, S, Type);
 	no_permission ->
-	    ac_not_started(Type, Name),
+	    _ = ac_not_started(Type, Name),
 	    {undefined, false}
     end.
 
@@ -850,11 +851,11 @@ wait_dist_start(Node, Appl, Name, Nodes, PermittedNodes, S, Type) ->
     monitor_node(Node, true),
     receive
 	{dist_ac_app_started, Node, Name, ok} ->
-	    ac_started(Type, Name, Node),
+	    _ = ac_started(Type, Name, Node),
 	    monitor_node(Node, false),
 	    {{distributed, Node}, false};
 	{dist_ac_app_started, Node, Name, {error, R}} ->
-	    ac_error(Type, Name, {Node, R}),
+	    _ = ac_error(Type, Name, {Node, R}),
 	    monitor_node(Node, false),
 	    {Appl#appl.id, false};
 	{dist_ac_weight, Name, _Weigth, Node} ->
@@ -883,10 +884,10 @@ wait_dist_start(Node, Appl, Name, Nodes, PermittedNodes, S, Type) ->
 wait_dist_start2(Appl, Name, Nodes, PermittedNodes, S, Type) ->
     receive
 	{dist_ac_app_started, Node, Name, ok} ->
-	    ac_started(Type, Name, Node),
+	    _ = ac_started(Type, Name, Node),
 	    {{distributed, Node}, false};
 	{dist_ac_app_started, Node, Name, {error, R}} ->
-	    ac_error(Type, Name, {Node, R}),
+	    _ = ac_error(Type, Name, {Node, R}),
 	    {Appl#appl.id, false};
 	{nodedown, Node} ->
 	    %% A node went down, try to start the app again - there may not
@@ -974,7 +975,7 @@ permit(false, {value, _}, AppName, From, S, _LockId) ->
     case dist_get_runnable_nodes(S#state.appls, AppName) of
 	[] ->
 	    %% There is no runnable node; stop application
-	    ac_stop_it(AppName),
+	    _ = ac_stop_it(AppName),
 	    SReqs = [{AppName, From} | S#state.s_reqs],
 	    {noreply, S#state{s_reqs = SReqs}};
 	Nodes ->
@@ -1155,7 +1156,8 @@ send_nodes(Nodes, Msg) ->
 	    end, FlatNodes).
 
 send_after(Time, Msg) when is_integer(Time), Time >= 0 ->
-    spawn_link(?MODULE, send_timeout, [self(), Time, Msg]);
+    _Pid = spawn_link(?MODULE, send_timeout, [self(), Time, Msg]),
+    ok;
 send_after(_,_) -> % infinity
     ok.
 
@@ -1305,7 +1307,7 @@ check_waiting([{From, AppName, false, Nodes} | Reqs],
 	      S, Node, Appls, Res, SReqs) ->
     case lists:delete(Node, Nodes) of
 	[] ->
-	    ac_stop_it(AppName),
+	    _ = ac_stop_it(AppName),
 	    NSReqs = [{AppName, From} | SReqs],
 	    check_waiting(Reqs, Node, S, Appls, Res, NSReqs);
 	NNodes ->
diff --git a/lib/kernel/src/erl_boot_server.erl b/lib/kernel/src/erl_boot_server.erl
index 0d68d3e198..9a49655a9f 100644
--- a/lib/kernel/src/erl_boot_server.erl
+++ b/lib/kernel/src/erl_boot_server.erl
@@ -1,7 +1,7 @@
 %%
 %% %CopyrightBegin%
 %%
-%% Copyright Ericsson AB 1996-2011. All Rights Reserved.
+%% Copyright Ericsson AB 1996-2013. All Rights Reserved.
 %%
 %% The contents of this file are subject to the Erlang Public License,
 %% Version 1.1, (the "License"); you may not use this file except in
@@ -191,7 +191,7 @@ init(Slaves) ->
     {ok, UPort} = inet:port(U),
     Ref = make_ref(),
     Pid = proc_lib:spawn_link(?MODULE, boot_init, [Ref]),
-    gen_tcp:controlling_process(L, Pid),
+    ok = gen_tcp:controlling_process(L, Pid),
     Pid ! {Ref, L},
     %% We trap exit inorder to restart boot_init and udp_port 
     process_flag(trap_exit, true),
@@ -233,9 +233,19 @@ handle_info({udp, U, IP, Port, Data}, S0) ->
     %% erlang version as the boot server node
     case {Valid,Data,Token} of
 	{true,Token,Token} ->
-	    gen_udp:send(U,IP,Port,[?EBOOT_REPLY,S0#state.priority,
-				    int16(S0#state.listen_port),
-				    S0#state.version]),
+	    case gen_udp:send(U,IP,Port,[?EBOOT_REPLY,S0#state.priority,
+                                         int16(S0#state.listen_port),
+                                         S0#state.version])
+            of
+                ok -> ok;
+                {error, not_owner} ->
+                    error_logger:error_msg("** Illegal boot server connection attempt: "
+				   "not owner of ~w ** ~n", [U]);
+                {error, Reason} ->
+                    Err = file:format_error(Reason),
+                    error_logger:error_msg("** Illegal boot server connection attempt: "
+				   "~w POSIX error ** ~n", [U, Err])
+            end,
 	    {noreply,S0};
 	{false,_,_} ->
 	    error_logger:error_msg("** Illegal boot server connection attempt: "
@@ -351,7 +361,14 @@ handle_command(S, PS, Msg) ->
     end.
 
 send_file_result(S, Cmd, Result) ->
-    gen_tcp:send(S, term_to_binary({Cmd,Result})).
-
-send_result(S, Result) ->
-    gen_tcp:send(S, term_to_binary(Result)).
+    send_result(S, {Cmd,Result}).
+
+send_result(S, Term) ->
+    case gen_tcp:send(S, term_to_binary(Term)) of
+	ok ->
+	    ok;
+	Error ->
+	    error_logger:error_msg("** Boot server could not send result "
+				   "to socket: ~w** ~n", [Error]),
+	    ok
+    end.
diff --git a/lib/kernel/src/erl_epmd.erl b/lib/kernel/src/erl_epmd.erl
index 91af49f303..b4fae24ef3 100644
--- a/lib/kernel/src/erl_epmd.erl
+++ b/lib/kernel/src/erl_epmd.erl
@@ -1,7 +1,7 @@
 %%
 %% %CopyrightBegin%
 %%
-%% Copyright Ericsson AB 1998-2010. All Rights Reserved.
+%% Copyright Ericsson AB 1998-2013. All Rights Reserved.
 %%
 %% The contents of this file are subject to the Erlang Public License,
 %% Version 1.1, (the "License"); you may not use this file except in
@@ -217,17 +217,23 @@ do_register_node(NodeName, TcpPort) ->
 	    Extra = "",
 	    Elen = length(Extra),
 	    Len = 1+2+1+1+2+2+2+length(Name)+2+Elen,
-	    gen_tcp:send(Socket, [?int16(Len), ?EPMD_ALIVE2_REQ,
-				   ?int16(TcpPort),
-				   $M,
-				   0,
-				   ?int16(epmd_dist_high()),
-				   ?int16(epmd_dist_low()),
-				   ?int16(length(Name)),
-				   Name,
-				   ?int16(Elen),
-				   Extra]),
-	    wait_for_reg_reply(Socket, []);
+            Packet = [?int16(Len), ?EPMD_ALIVE2_REQ,
+                      ?int16(TcpPort),
+                      $M,
+                      0,
+                      ?int16(epmd_dist_high()),
+                      ?int16(epmd_dist_low()),
+                      ?int16(length(Name)),
+                      Name,
+                      ?int16(Elen),
+                      Extra],
+	    case gen_tcp:send(Socket, Packet) of
+                ok ->
+                    wait_for_reg_reply(Socket, []);
+                Error ->
+                    close(Socket),
+                    Error
+            end;
 	Error ->
 	    Error
     end.
@@ -294,8 +300,14 @@ get_port(Node, EpmdAddress, Timeout) ->
 	{ok, Socket} ->
 	    Name = to_string(Node),
 	    Len = 1+length(Name),
-	    gen_tcp:send(Socket, [?int16(Len),?EPMD_PORT_PLEASE2_REQ, Name]),
-	    wait_for_port_reply(Socket, []);
+	    Msg = [?int16(Len),?EPMD_PORT_PLEASE2_REQ,Name],
+	    case gen_tcp:send(Socket, Msg) of
+		ok ->
+		    wait_for_port_reply(Socket, []);
+		_Error ->
+		    ?port_please_failure2(_Error),
+		    noport
+	    end;
 	_Error -> 
 	    ?port_please_failure2(_Error),
 	    noport
@@ -374,7 +386,7 @@ wait_for_port_reply_name(Socket, Len, Sofar) ->
 %	    io:format("data = ~p~n", _Data),
 	    wait_for_port_reply_name(Socket, Len, Sofar);
 	{tcp_closed, Socket} ->
-	    "foobar"
+	    ok
     end.
 		    
 
@@ -424,19 +436,24 @@ get_names(EpmdAddress) ->
     end.
 
 do_get_names(Socket) ->
-    gen_tcp:send(Socket, [?int16(1),?EPMD_NAMES]),
-    receive
-	{tcp, Socket, [P0,P1,P2,P3|T]} ->
-	    EpmdPort = ?u32(P0,P1,P2,P3),
-	    case get_epmd_port() of
-		EpmdPort ->
-		    names_loop(Socket, T, []);
-		_ ->
-		    close(Socket),
-		    {error, address}
+    case gen_tcp:send(Socket, [?int16(1),?EPMD_NAMES]) of
+	ok ->
+	    receive
+		{tcp, Socket, [P0,P1,P2,P3|T]} ->
+		    EpmdPort = ?u32(P0,P1,P2,P3),
+		    case get_epmd_port() of
+			EpmdPort ->
+			    names_loop(Socket, T, []);
+			_ ->
+			    close(Socket),
+			    {error, address}
+		    end;
+		{tcp_closed, Socket} ->
+		    {ok, []}
 	    end;
-	{tcp_closed, Socket} ->
-	    {ok, []}
+	_ ->
+	    close(Socket),
+	    {error, address}
     end.
 
 names_loop(Socket, Acc, Ps) ->
diff --git a/lib/kernel/src/erl_reply.erl b/lib/kernel/src/erl_reply.erl
index 1a61e630bc..f0be3ee654 100644
--- a/lib/kernel/src/erl_reply.erl
+++ b/lib/kernel/src/erl_reply.erl
@@ -1,7 +1,7 @@
 %%
 %% %CopyrightBegin%
 %% 
-%% Copyright Ericsson AB 1997-2009. All Rights Reserved.
+%% Copyright Ericsson AB 1997-2013. All Rights Reserved.
 %% 
 %% The contents of this file are subject to the Erlang Public License,
 %% Version 1.1, (the "License"); you may not use this file except in
@@ -32,7 +32,7 @@ reply([Addr,Port,Msg]) ->
     P = list_to_integer(atom_to_list(Port)),
     M = atom_to_list(Msg),
     {ok, S} = gen_tcp:connect(Ip,P,[]),
-    gen_tcp:send(S,M),
+    ok = gen_tcp:send(S,M),
     gen_tcp:close(S),
     reply_done;
 reply(_) ->
diff --git a/lib/kernel/src/error_logger.erl b/lib/kernel/src/error_logger.erl
index 92c1eb80dc..b8fbf02feb 100644
--- a/lib/kernel/src/error_logger.erl
+++ b/lib/kernel/src/error_logger.erl
@@ -1,7 +1,7 @@
 %%
 %% %CopyrightBegin%
 %% 
-%% Copyright Ericsson AB 1996-2012. All Rights Reserved.
+%% Copyright Ericsson AB 1996-2013. All Rights Reserved.
 %% 
 %% The contents of this file are subject to the Erlang Public License,
 %% Version 1.1, (the "License"); you may not use this file except in
@@ -245,16 +245,18 @@ notify(Msg) ->
 -spec swap_handler(Type :: swap_handler_type()) -> any().
 
 swap_handler(tty) ->
-    gen_event:swap_handler(error_logger, {error_logger, swap},
-			   {error_logger_tty_h, []}),
-    simple_logger();
+    R = gen_event:swap_handler(error_logger, {error_logger, swap},
+                               {error_logger_tty_h, []}),
+    ok = simple_logger(),
+    R;
 swap_handler({logfile, File}) ->
-    gen_event:swap_handler(error_logger, {error_logger, swap},
-			   {error_logger_file_h, File}),
-    simple_logger();
+    R = gen_event:swap_handler(error_logger, {error_logger, swap},
+                               {error_logger_file_h, File}),
+    ok = simple_logger(),
+    R;
 swap_handler(silent) ->
-    gen_event:delete_handler(error_logger, error_logger, delete),
-    simple_logger();
+    _ = gen_event:delete_handler(error_logger, error_logger, delete),
+    ok = simple_logger();
 swap_handler(false) ->
     ok. % keep primitive event handler as-is
 
diff --git a/lib/kernel/src/erts_debug.erl b/lib/kernel/src/erts_debug.erl
index 6654cd9ee7..f7a815882b 100644
--- a/lib/kernel/src/erts_debug.erl
+++ b/lib/kernel/src/erts_debug.erl
@@ -1,7 +1,7 @@
 %%
 %% %CopyrightBegin%
 %% 
-%% Copyright Ericsson AB 1999-2012. All Rights Reserved.
+%% Copyright Ericsson AB 1999-2013. All Rights Reserved.
 %% 
 %% The contents of this file are subject to the Erlang Public License,
 %% Version 1.1, (the "License"); you may not use this file except in
@@ -288,7 +288,7 @@ dff(Name, Fs) when is_list(Name) ->
 	    try
 		dff(F, Fs)
 	    after
-		file:close(F)
+		_ = file:close(F)
 	    end;
 	{error,Reason} ->
 	    {error,{badopen,Reason}}
diff --git a/lib/kernel/src/file.erl b/lib/kernel/src/file.erl
index 36289053eb..5c0f3b7ceb 100644
--- a/lib/kernel/src/file.erl
+++ b/lib/kernel/src/file.erl
@@ -376,7 +376,7 @@ write_file(Name, Bin, ModeList) when is_list(ModeList) ->
 			ok ->
 			    close(Handle);
 			E1 ->
-			    close(Handle),
+			    _ = close(Handle),
 			    E1
 		    end;
 		E2 ->
@@ -770,7 +770,7 @@ copy_int({SourceName, SourceOpts}, Dest, Length)
 	    case open(Source, [read | SourceOpts]) of
 		{ok, Handle} ->
 		    Result = copy_opened_int(Handle, Dest, Length, 0),
-		    close(Handle),
+		    _ = close(Handle),
 		    Result;
 		{error, _} = Error ->
 		    Error
@@ -786,9 +786,16 @@ copy_int(Source, {DestName, DestOpts}, Length)
 	Dest ->
 	    case open(Dest, [write | DestOpts]) of
 		{ok, Handle} ->
-		    Result = copy_opened_int(Source, Handle, Length, 0),
-		    close(Handle),
-		    Result;
+                    case copy_opened_int(Source, Handle, Length, 0) of
+                        {ok, _} = OK ->
+                            case close(Handle) of
+                                ok -> OK;
+                                Error -> Error
+                            end;
+                        Error ->
+                            _ = close(Handle),
+                            Error
+                    end;
 		{error, _} = Error ->
 		    Error
 	    end
@@ -957,7 +964,7 @@ consult(File) ->
     case open(File, [read]) of
 	{ok, Fd} ->
 	    R = consult_stream(Fd),
-	    close(Fd),
+	    _ = close(Fd),
 	    R;
 	Error ->
 	    Error
@@ -977,10 +984,10 @@ path_consult(Path, File) ->
 	{ok, Fd, Full} ->
 	    case consult_stream(Fd) of
 		{ok, List} ->
-		    close(Fd),
+		    _ = close(Fd),
 		    {ok, List, Full};
 		E1 ->
-		    close(Fd),
+		    _ = close(Fd),
 		    E1
 	    end;
 	E2 ->
@@ -1005,7 +1012,7 @@ eval(File, Bs) ->
     case open(File, [read]) of
 	{ok, Fd} ->
 	    R = eval_stream(Fd, ignore, Bs),
-	    close(Fd),
+	    _ = close(Fd),
 	    R;
 	Error ->
 	    Error
@@ -1035,10 +1042,10 @@ path_eval(Path, File, Bs) ->
 	{ok, Fd, Full} ->
 	    case eval_stream(Fd, ignore, Bs) of
 		ok ->
-		    close(Fd),
+		    _ = close(Fd),
 		    {ok, Full};
 		E1 ->
-		    close(Fd),
+		    _ = close(Fd),
 		    E1
 	    end;
 	E2 ->
@@ -1065,7 +1072,7 @@ script(File, Bs) ->
     case open(File, [read]) of
 	{ok, Fd} ->
 	    R = eval_stream(Fd, return, Bs),
-	    close(Fd),
+	    _ = close(Fd),
 	    R;
 	Error ->
 	    Error
@@ -1098,10 +1105,10 @@ path_script(Path, File, Bs) ->
 	{ok,Fd,Full} ->
 	    case eval_stream(Fd, return, Bs) of
 		{ok,R} ->
-		    close(Fd),
+		    _ = close(Fd),
 		    {ok, R, Full};
 		E1 ->
-		    close(Fd),
+		    _ = close(Fd),
 		    E1
 	    end;
 	E2 ->
@@ -1247,7 +1254,7 @@ sendfile(Filename, Sock)  ->
 	    {error, Reason};
 	{ok, Fd} ->
 	    Res = sendfile(Fd, Sock, 0, 0, []),
-	    file:close(Fd),
+	    _ = file:close(Fd),
 	    Res
     end.
 
@@ -1298,7 +1305,7 @@ sendfile_fallback(File, Sock, Offset, Bytes, ChunkSize) ->
     {ok, CurrPos} = file:position(File, {cur, 0}),
     {ok, _NewPos} = file:position(File, {bof, Offset}),
     Res = sendfile_fallback_int(File, Sock, Bytes, ChunkSize, 0),
-    file:position(File, {bof, CurrPos}),
+    _ = file:position(File, {bof, CurrPos}),
     Res.
 
 
diff --git a/lib/kernel/src/file_io_server.erl b/lib/kernel/src/file_io_server.erl
index 07fb55f390..0e9ff5bc0f 100644
--- a/lib/kernel/src/file_io_server.erl
+++ b/lib/kernel/src/file_io_server.erl
@@ -1,7 +1,7 @@
 %%
 %% %CopyrightBegin%
 %%
-%% Copyright Ericsson AB 2000-2012. All Rights Reserved.
+%% Copyright Ericsson AB 2000-2013. All Rights Reserved.
 %%
 %% The contents of this file are subject to the Erlang Public License,
 %% Version 1.1, (the "License"); you may not use this file except in
@@ -162,29 +162,29 @@ server_loop(#state{mref = Mref} = State) ->
 	{file_request, From, ReplyAs, Request} when is_pid(From) ->
 	    case file_request(Request, State) of
 		{reply, Reply, NewState} ->
-		    file_reply(From, ReplyAs, Reply),
+		    _ = file_reply(From, ReplyAs, Reply),
 		    server_loop(NewState);
 		{error, Reply, NewState} ->
 		    %% error is the same as reply, except that
 		    %% it breaks the io_request_loop further down
-		    file_reply(From, ReplyAs, Reply),
+		    _ = file_reply(From, ReplyAs, Reply),
 		    server_loop(NewState);
 		{stop, Reason, Reply, _NewState} ->
-		    file_reply(From, ReplyAs, Reply),
+		    _ = file_reply(From, ReplyAs, Reply),
 		    exit(Reason)
 	    end;
 	{io_request, From, ReplyAs, Request} when is_pid(From) ->
 	    case io_request(Request, State) of
 		{reply, Reply, NewState} ->
-		    io_reply(From, ReplyAs, Reply),
+		    _ = io_reply(From, ReplyAs, Reply),
 		    server_loop(NewState);
 		{error, Reply, NewState} ->
 		    %% error is the same as reply, except that
 		    %% it breaks the io_request_loop further down
-		    io_reply(From, ReplyAs, Reply),
+		    _ = io_reply(From, ReplyAs, Reply),
 		    server_loop(NewState);
 		{stop, Reason, Reply, _NewState} ->
-		    io_reply(From, ReplyAs, Reply),
+		    _ = io_reply(From, ReplyAs, Reply),
 		    exit(Reason)
 	    end;
 	{'DOWN', Mref, _, _, Reason} ->
diff --git a/lib/kernel/src/file_server.erl b/lib/kernel/src/file_server.erl
index d036dbb516..eabf0401a3 100644
--- a/lib/kernel/src/file_server.erl
+++ b/lib/kernel/src/file_server.erl
@@ -78,7 +78,8 @@ init([]) ->
     process_flag(trap_exit, true),
     case ?PRIM_FILE:start() of
 	{ok, Handle} ->
-	    ets:new(?FILE_IO_SERVER_TABLE, [named_table]),
+	    ?FILE_IO_SERVER_TABLE =
+                ets:new(?FILE_IO_SERVER_TABLE, [named_table]),
 	    {ok, Handle};
 	{error, Reason} ->
 	    {stop, Reason}
diff --git a/lib/kernel/src/gen_sctp.erl b/lib/kernel/src/gen_sctp.erl
index 74ad192802..81c9fbe55f 100644
--- a/lib/kernel/src/gen_sctp.erl
+++ b/lib/kernel/src/gen_sctp.erl
@@ -1,7 +1,7 @@
 %%
 %% %CopyrightBegin%
 %%
-%% Copyright Ericsson AB 2007-2012. All Rights Reserved.
+%% Copyright Ericsson AB 2007-2013. All Rights Reserved.
 %%
 %% The contents of this file are subject to the Erlang Public License,
 %% Version 1.1, (the "License"); you may not use this file except in
@@ -270,7 +270,7 @@ do_connect(S, Addr, Port, Opts, Timeout, ConnWait) when is_port(S), is_list(Opts
 				    Mod:connect(S, IP, Port, Opts, ConnectTimer);
 				Error -> Error
 			    after
-				inet:stop_timer(Timer)
+				_ = inet:stop_timer(Timer)
 			    end
 		    catch
 			error:badarg ->
diff --git a/lib/kernel/src/gen_tcp.erl b/lib/kernel/src/gen_tcp.erl
index a98ed4c238..96026aa428 100644
--- a/lib/kernel/src/gen_tcp.erl
+++ b/lib/kernel/src/gen_tcp.erl
@@ -139,7 +139,7 @@ connect(Address, Port, Opts) ->
 connect(Address, Port, Opts, Time) ->
     Timer = inet:start_timer(Time),
     Res = (catch connect1(Address,Port,Opts,Timer)),
-    inet:stop_timer(Timer),
+    _ = inet:stop_timer(Timer),
     case Res of
 	{ok,S} -> {ok,S};
 	{error, einval} -> exit(badarg);
diff --git a/lib/kernel/src/global.erl b/lib/kernel/src/global.erl
index b24a9d5eac..ef878b8d0c 100644
--- a/lib/kernel/src/global.erl
+++ b/lib/kernel/src/global.erl
@@ -1,7 +1,7 @@
 %%
 %% %CopyrightBegin%
 %%
-%% Copyright Ericsson AB 1996-2012. All Rights Reserved.
+%% Copyright Ericsson AB 1996-2013. All Rights Reserved.
 %%
 %% The contents of this file are subject to the Erlang Public License,
 %% Version 1.1, (the "License"); you may not use this file except in
@@ -2069,7 +2069,8 @@ random_sleep(Times) ->
     case get(random_seed) of
 	undefined ->
 	    {A1, A2, A3} = now(),
-	    random:seed(A1, A2, A3 + erlang:phash(node(), 100000));
+	    _ = random:seed(A1, A2, A3 + erlang:phash(node(), 100000)),
+            ok;
 	_ -> ok
     end,
     %% First time 1/4 seconds, then doubling each time up to 8 seconds max.
diff --git a/lib/kernel/src/global_group.erl b/lib/kernel/src/global_group.erl
index 025a9b8a5b..da8b573749 100644
--- a/lib/kernel/src/global_group.erl
+++ b/lib/kernel/src/global_group.erl
@@ -1,7 +1,7 @@
 %%
 %% %CopyrightBegin%
 %% 
-%% Copyright Ericsson AB 1998-2011. All Rights Reserved.
+%% Copyright Ericsson AB 1998-2013. All Rights Reserved.
 %% 
 %% The contents of this file are subject to the Erlang Public License,
 %% Version 1.1, (the "License"); you may not use this file except in
@@ -1149,9 +1149,14 @@ do_unlink(Pid, State) ->
 %%%====================================================================================
 %%% Send a nodeup/down messages to monitoring Pids in the own global group.
 %%%====================================================================================
-send_monitor([P|T], M, no_conf) -> safesend_nc(P, M), send_monitor(T, M, no_conf);
-send_monitor([P|T], M, SyncState) -> safesend(P, M), send_monitor(T, M, SyncState);
-send_monitor([], _, _) -> ok.
+send_monitor([P|T], M, no_conf) ->
+    _ = safesend_nc(P, M),
+    send_monitor(T, M, no_conf);
+send_monitor([P|T], M, SyncState) ->
+    _ = safesend(P, M),
+    send_monitor(T, M, SyncState);
+send_monitor([], _, _) ->
+    ok.
 
 safesend(Name, {Msg, Node}) when is_atom(Name) ->
     case lists:member(Node, get_own_nodes()) of
diff --git a/lib/kernel/src/group.erl b/lib/kernel/src/group.erl
index ff835e1047..b36dbf33dd 100644
--- a/lib/kernel/src/group.erl
+++ b/lib/kernel/src/group.erl
@@ -309,15 +309,17 @@ io_requests([], Stat, _) ->
 %%  The ACK contains the return value.
 
 io_reply(From, ReplyAs, Reply) ->
-    From ! {io_reply,ReplyAs,Reply}.
+    From ! {io_reply,ReplyAs,Reply},
+    ok.
 
 %% send_drv(Drv, Message)
 %% send_drv_reqs(Drv, Requests)
 
 send_drv(Drv, Msg) ->
-    Drv ! {self(),Msg}.
+    Drv ! {self(),Msg},
+    ok.
 
-send_drv_reqs(_Drv, []) -> [];
+send_drv_reqs(_Drv, []) -> ok;
 send_drv_reqs(Drv, Rs) ->
     send_drv(Drv, {requests,Rs}).
 
diff --git a/lib/kernel/src/heart.erl b/lib/kernel/src/heart.erl
index 87cb9d7f51..aa65c3a474 100644
--- a/lib/kernel/src/heart.erl
+++ b/lib/kernel/src/heart.erl
@@ -1,7 +1,7 @@
 %%
 %% %CopyrightBegin%
 %%
-%% Copyright Ericsson AB 1996-2012. All Rights Reserved.
+%% Copyright Ericsson AB 1996-2013. All Rights Reserved.
 %%
 %% The contents of this file are subject to the Erlang Public License,
 %% Version 1.1, (the "License"); you may not use this file except in
@@ -182,11 +182,11 @@ wait_ack(Port) ->
     end.
 
 loop(Parent, Port, Cmd) ->
-    send_heart_beat(Port),
+    _ = send_heart_beat(Port),
     receive
 	{From, set_cmd, NewCmd} when length(NewCmd) < 2047 ->
-	    send_heart_cmd(Port, NewCmd),
-	    wait_ack(Port),
+	    _ = send_heart_cmd(Port, NewCmd),
+	    _ = wait_ack(Port),
 	    From ! {heart, ok},
 	    loop(Parent, Port, NewCmd);
 	{From, set_cmd, NewCmd} ->
@@ -194,8 +194,8 @@ loop(Parent, Port, Cmd) ->
 	    loop(Parent, Port, Cmd);
 	{From, clear_cmd} ->
 	    From ! {heart, ok},
-	    send_heart_cmd(Port, ""),
-	    wait_ack(Port),
+	    _ = send_heart_cmd(Port, ""),
+	    _ = wait_ack(Port),
 	    loop(Parent, Port, "");
 	{From, get_cmd} ->
 	    From ! {heart, get_heart_cmd(Port)},
@@ -222,7 +222,7 @@ loop(Parent, Port, Cmd) ->
 -spec no_reboot_shutdown(port()) -> no_return().
 
 no_reboot_shutdown(Port) ->
-    send_shutdown(Port),
+    _ = send_shutdown(Port),
     receive
 	{'EXIT', Port, Reason} when Reason =/= badsig ->
 	    exit(normal)
@@ -232,10 +232,10 @@ do_cycle_port_program(Caller, Parent, Port, Cmd) ->
     unregister(?HEART_PORT_NAME),
     case catch start_portprogram() of
 	{ok, NewPort} ->
-	    send_shutdown(Port),
+	    _ = send_shutdown(Port),
 	    receive
 		{'EXIT', Port, _Reason} ->
-		    send_heart_cmd(NewPort, Cmd),
+		    _ = send_heart_cmd(NewPort, Cmd),
 		    Caller ! {heart, ok},
 		    loop(Parent, NewPort, Cmd)
 	    after
@@ -243,7 +243,7 @@ do_cycle_port_program(Caller, Parent, Port, Cmd) ->
 		    %% Huh! Two heart port programs running...
 		    %% well, the old one has to be sick not to respond
 		    %% so we'll settle for the new one...
-		    send_heart_cmd(NewPort, Cmd),
+		    _ = send_heart_cmd(NewPort, Cmd),
 		    Caller ! {heart, {error, stop_error}},
 		    loop(Parent, NewPort, Cmd)
 	    end;
diff --git a/lib/kernel/src/hipe_unified_loader.erl b/lib/kernel/src/hipe_unified_loader.erl
index e676ca997d..cc51b5ae07 100644
--- a/lib/kernel/src/hipe_unified_loader.erl
+++ b/lib/kernel/src/hipe_unified_loader.erl
@@ -226,14 +226,16 @@ load_common(Mod, Bin, Beam, OldReferencesToPatch) ->
       %%  (patches the BEAM code to redirect to native.)
       case Beam of
 	[] ->
-	  export_funs(Addresses);
+	  export_funs(Addresses),
+	  ok;
 	BeamBinary when is_binary(BeamBinary) ->
 	  %% Find all closures in the code.
 	  ClosurePatches = find_closure_patches(Refs),
 	  AddressesOfClosuresToPatch =
 	    calculate_addresses(ClosurePatches, CodeAddress, Addresses),
 	  export_funs(Addresses),
-	  export_funs(Mod, BeamBinary, Addresses, AddressesOfClosuresToPatch)
+	  export_funs(Mod, BeamBinary, Addresses, AddressesOfClosuresToPatch),
+	  ok
       end,
       %% Redirect references to the old module to the new module's BEAM stub.
       patch_to_emu_step2(OldReferencesToPatch),
diff --git a/lib/kernel/src/inet.erl b/lib/kernel/src/inet.erl
index 9670271b2e..ad6b265b83 100644
--- a/lib/kernel/src/inet.erl
+++ b/lib/kernel/src/inet.erl
@@ -1,7 +1,7 @@
 %%
 %% %CopyrightBegin%
 %%
-%% Copyright Ericsson AB 1997-2012. All Rights Reserved.
+%% Copyright Ericsson AB 1997-2013. All Rights Reserved.
 %%
 %% The contents of this file are subject to the Erlang Public License,
 %% Version 1.1, (the "License"); you may not use this file except in
@@ -389,7 +389,7 @@ gethostbyname(Name,Family) ->
 gethostbyname(Name,Family,Timeout) ->
     Timer = start_timer(Timeout),
     Res = gethostbyname_tm(Name,Family,Timer),
-    stop_timer(Timer),
+    _ = stop_timer(Timer),
     Res.
 
 gethostbyname_tm(Name,Family,Timer) ->
@@ -420,7 +420,7 @@ gethostbyaddr(Address) ->
 gethostbyaddr(Address,Timeout) ->
     Timer = start_timer(Timeout),    
     Res = gethostbyaddr_tm(Address, Timer),
-    stop_timer(Timer),
+    _ = stop_timer(Timer),
     Res.
 
 gethostbyaddr_tm(Address,Timer) ->
@@ -475,7 +475,7 @@ getaddr(Address, Family) ->
 getaddr(Address, Family, Timeout) ->
     Timer = start_timer(Timeout),
     Res = getaddr_tm(Address, Family, Timer),
-    stop_timer(Timer),
+    _ = stop_timer(Timer),
     Res.
 
 getaddr_tm(Address, Family, Timer) ->
@@ -501,7 +501,7 @@ getaddrs(Address, Family) ->
 getaddrs(Address, Family, Timeout) ->
     Timer = start_timer(Timeout),
     Res = getaddrs_tm(Address, Family, Timer),
-    stop_timer(Timer),
+    _ = stop_timer(Timer),
     Res.
 
 -spec getservbyport(Port :: port_number(), Protocol :: atom() | string()) ->
@@ -1331,7 +1331,7 @@ tcp_controlling_process(S, NewOwner) when is_port(S), is_pid(NewOwner) ->
 		{ok, A0} ->
 		    case A0 of
 			false -> ok;
-			_ -> prim_inet:setopt(S, active, false)
+			_ -> ok = prim_inet:setopt(S, active, false)
 		    end,
 		    case tcp_sync_input(S, NewOwner, false) of
 			true ->  %% socket already closed, 
@@ -1342,7 +1342,7 @@ tcp_controlling_process(S, NewOwner) when is_port(S), is_pid(NewOwner) ->
 				    unlink(S), %% unlink from port
 				    case A0 of
 					false -> ok;
-					_ -> prim_inet:setopt(S, active, A0)
+					_ -> ok = prim_inet:setopt(S, active, A0)
 				    end,
 				    ok
 			    catch
@@ -1385,13 +1385,12 @@ udp_controlling_process(S, NewOwner) when is_port(S), is_pid(NewOwner) ->
 	    {error, not_owner};
 	_ ->
 	    {ok, A0} = prim_inet:getopt(S, active),
-	    prim_inet:setopt(S, active, false),
+	    ok = prim_inet:setopt(S, active, false),
 	    udp_sync_input(S, NewOwner),
 	    try erlang:port_connect(S, NewOwner) of
 		true -> 
 		    unlink(S),
-		    prim_inet:setopt(S, active, A0),
-		    ok
+		    ok = prim_inet:setopt(S, active, A0)
 	    catch
 		error:Reason -> 
 		    {error, Reason}
diff --git a/lib/kernel/src/inet6_tcp_dist.erl b/lib/kernel/src/inet6_tcp_dist.erl
index 2cb0e10c87..459fdc2ad5 100644
--- a/lib/kernel/src/inet6_tcp_dist.erl
+++ b/lib/kernel/src/inet6_tcp_dist.erl
@@ -92,7 +92,7 @@ accept_loop(Kernel, Listen) ->
     case inet6_tcp:accept(Listen) of
         {ok, Socket} ->
             Kernel ! {accept,self(),Socket,inet6,tcp},
-            controller(Kernel, Socket),
+            _ = controller(Kernel, Socket),
             accept_loop(Kernel, Listen);
         Error ->
             exit(Error)
diff --git a/lib/kernel/src/inet_db.erl b/lib/kernel/src/inet_db.erl
index d4749b9756..8a2994579b 100644
--- a/lib/kernel/src/inet_db.erl
+++ b/lib/kernel/src/inet_db.erl
@@ -1,7 +1,7 @@
 %%
 %% %CopyrightBegin%
 %%
-%% Copyright Ericsson AB 1997-2010. All Rights Reserved.
+%% Copyright Ericsson AB 1997-2013. All Rights Reserved.
 %%
 %% The contents of this file are subject to the Erlang Public License,
 %% Version 1.1, (the "License"); you may not use this file except in
@@ -1112,7 +1112,7 @@ handle_call(Request, From, #state{db=Db}=State) ->
 	{set_cache_refresh, Time} when is_integer(Time), Time > 0 ->
 	    Time1 = ((Time+999) div 1000)*1000, %% round up
 	    ets:insert(Db, {cache_refresh_interval, Time1}),
-	    stop_timer(State#state.cache_timer),
+	    _ = stop_timer(State#state.cache_timer),
 	    {reply, ok, State#state{cache_timer = init_timer()}};
 
 	clear_hosts ->
@@ -1126,7 +1126,7 @@ handle_call(Request, From, #state{db=Db}=State) ->
 
 	reset ->
 	    reset_db(Db),
-	    stop_timer(State#state.cache_timer),
+	    _ = stop_timer(State#state.cache_timer),
 	    {reply, ok, State#state{cache_timer = init_timer()}};
 
 	{add_rc_list, List} ->
@@ -1176,7 +1176,7 @@ handle_info(_Info, State) ->
 -spec terminate(term(), state()) -> 'ok'.
 
 terminate(_Reason, State) ->
-    stop_timer(State#state.cache_timer),
+    _ = stop_timer(State#state.cache_timer),
     ok.
 
 %%%----------------------------------------------------------------------
@@ -1233,7 +1233,7 @@ do_add_host(Byname, Byaddr, Names, Type, IP) ->
     ok.
 
 do_del_host(Byname, Byaddr, IP) ->
-    [ets:delete_object(Byname, NIP) || NIP <- ets:lookup(Byaddr, IP)],
+    _ = [ets:delete_object(Byname, NIP) || NIP <- ets:lookup(Byaddr, IP)],
     ets:delete(Byaddr, IP),
     ok.
 
diff --git a/lib/kernel/src/inet_gethost_native.erl b/lib/kernel/src/inet_gethost_native.erl
index df866660b4..4320987078 100644
--- a/lib/kernel/src/inet_gethost_native.erl
+++ b/lib/kernel/src/inet_gethost_native.erl
@@ -1,7 +1,7 @@
 %%
 %% %CopyrightBegin%
 %%
-%% Copyright Ericsson AB 1998-2010. All Rights Reserved.
+%% Copyright Ericsson AB 1998-2013. All Rights Reserved.
 %%
 %% The contents of this file are subject to the Erlang Public License,
 %% Version 1.1, (the "License"); you may not use this file except in
@@ -237,7 +237,7 @@ handle_message({Port, {data, Data}}, State = #state{port = Port}) ->
 				       State;
 				   Req ->
 				       lists:foreach(fun({P,R,TR}) ->
-							     ?CANCEL_TIMER(TR),
+							     _= ?CANCEL_TIMER(TR),
 							     P ! {R,
 								  {ok,
 								   BinReply}}
@@ -276,7 +276,7 @@ handle_message({timeout, Pid, RID}, State) ->
 	{last, {LP,LR,_}} ->
 	    LP ! {LR, {error,timeout}},
 	    %% Remove the whole request structure...
-	    pick_request(State, RID),
+	    _ = pick_request(State, RID),
 	    %% Also cancel the request to the port program...
 	    (catch port_command(State#state.port, 
 				<<RID:32,?OP_CANCEL_REQUEST>>))
@@ -517,7 +517,7 @@ do_start(Sup, C) ->
 	{error, {{already_started, Pid}, _Child}} when is_pid(Pid) ->
 	    ok;
 	{error, already_present} ->
-	    supervisor:delete_child(Sup, Child),
+	    _ = supervisor:delete_child(Sup, Child),
 	    do_start(Sup, C)
     end.
 
diff --git a/lib/kernel/src/inet_parse.erl b/lib/kernel/src/inet_parse.erl
index 619c78a6ca..d24bda0c3d 100644
--- a/lib/kernel/src/inet_parse.erl
+++ b/lib/kernel/src/inet_parse.erl
@@ -288,7 +288,7 @@ parse_file(_, File, Fn) ->
     case file:open(File, [read]) of
 	{ok, Fd} ->
 	    Result = parse_fd(File,Fd, 1, Fn, []),
-	    file:close(Fd),
+	    _ = file:close(Fd),
 	    Result;
 	Error -> Error
     end.
diff --git a/lib/kernel/src/inet_res.erl b/lib/kernel/src/inet_res.erl
index 59ba408d7a..ab9cbf0617 100644
--- a/lib/kernel/src/inet_res.erl
+++ b/lib/kernel/src/inet_res.erl
@@ -1,7 +1,7 @@
 %%
 %% %CopyrightBegin%
 %%
-%% Copyright Ericsson AB 1997-2011. All Rights Reserved.
+%% Copyright Ericsson AB 1997-2013. All Rights Reserved.
 %%
 %% The contents of this file are subject to the Erlang Public License,
 %% Version 1.1, (the "License"); you may not use this file except in
@@ -139,7 +139,7 @@ resolve(Name, Class, Type, Opts, Timeout) ->
 	{ok, Nm} ->
 	    Timer = inet:start_timer(Timeout),
 	    Res = res_query(Nm, Class, Type, Opts, Timer),
-	    inet:stop_timer(Timer),
+	    _ = inet:stop_timer(Timer),
 	    Res;
 	Error ->
 	    Error
@@ -339,7 +339,7 @@ gethostbyaddr(IP) -> gethostbyaddr_tm(IP,false).
 gethostbyaddr(IP,Timeout) ->
     Timer = inet:start_timer(Timeout),
     Res = gethostbyaddr_tm(IP,Timer),
-    inet:stop_timer(Timer),
+    _ = inet:stop_timer(Timer),
     Res.    
 
 gethostbyaddr_tm({A,B,C,D} = IP, Timer) when ?ip(A,B,C,D) ->
@@ -424,7 +424,7 @@ gethostbyname(Name,Family) ->
 gethostbyname(Name,Family,Timeout) ->
     Timer = inet:start_timer(Timeout),    
     Res = gethostbyname_tm(Name,Family,Timer),
-    inet:stop_timer(Timer),
+    _ = inet:stop_timer(Timer),
     Res.
     
 gethostbyname_tm(Name,inet,Timer) ->
@@ -483,7 +483,7 @@ getbyname(Name, Type) ->
 getbyname(Name, Type, Timeout) ->
     Timer = inet:start_timer(Timeout),
     Res = getbyname_tm(Name, Type, Timer),
-    inet:stop_timer(Timer),
+    _ = inet:stop_timer(Timer),
     Res.
 
 getbyname_tm(Name, Type, Timer) when is_list(Name) ->
@@ -921,18 +921,25 @@ query_tcp(Timeout, Id, Buffer, IP, Port, Verbose) ->
 			[{active,false},{packet,2},binary,Family], 
 			Timeout) of
 	{ok, S} ->
-	    gen_tcp:send(S, Buffer),
-	    case gen_tcp:recv(S, 0, Timeout) of
-		{ok, Answer} ->
-		    gen_tcp:close(S),
-		    case decode_answer(Answer, Id, Verbose) of
-			{ok, _} = OK -> OK;
-			{error, badid} -> {error, servfail};
-			Error -> Error
+	    case gen_tcp:send(S, Buffer) of
+		ok ->
+		    case gen_tcp:recv(S, 0, Timeout) of
+			{ok, Answer} ->
+			    gen_tcp:close(S),
+			    case decode_answer(Answer, Id, Verbose) of
+				{ok, _} = OK -> OK;
+				{error, badid} -> {error, servfail};
+				Error -> Error
+			    end;
+			Error ->
+			    gen_tcp:close(S),
+			    ?verbose(Verbose, "TCP server recv error: ~p\n",
+				     [Error]),
+			    Error
 		    end;
 		Error ->
 		    gen_tcp:close(S),
-		    ?verbose(Verbose, "TCP server recv error: ~p\n",
+		    ?verbose(Verbose, "TCP server send error: ~p\n",
 			     [Error]),
 		    Error
 	    end;
diff --git a/lib/kernel/src/inet_sctp.erl b/lib/kernel/src/inet_sctp.erl
index 2d799d79fa..93528d305d 100644
--- a/lib/kernel/src/inet_sctp.erl
+++ b/lib/kernel/src/inet_sctp.erl
@@ -1,7 +1,7 @@
 %%
 %% %CopyrightBegin%
 %%
-%% Copyright Ericsson AB 2007-2011. All Rights Reserved.
+%% Copyright Ericsson AB 2007-2013. All Rights Reserved.
 %%
 %% The contents of this file are subject to the Erlang Public License,
 %% Version 1.1, (the "License"); you may not use this file except in
@@ -135,7 +135,7 @@ connect_get_assoc(S, Addr, Port, Active, Timer) ->
 	{sctp,S,Addr,Port,{_,#sctp_assoc_change{state=St}=Ev}} ->
 	    case Active of
 		once ->
-		    prim_inet:setopt(S, active, once);
+		    ok = prim_inet:setopt(S, active, once);
 		_ -> ok
 	    end,
 	    if St =:= comm_up ->
diff --git a/lib/kernel/src/inet_tcp_dist.erl b/lib/kernel/src/inet_tcp_dist.erl
index 8005eff58c..63f236b069 100644
--- a/lib/kernel/src/inet_tcp_dist.erl
+++ b/lib/kernel/src/inet_tcp_dist.erl
@@ -119,7 +119,7 @@ accept_loop(Kernel, Listen) ->
     case inet_tcp:accept(Listen) of
 	{ok, Socket} ->
 	    Kernel ! {accept,self(),Socket,inet,tcp},
-	    controller(Kernel, Socket),
+	    _ = controller(Kernel, Socket),
 	    accept_loop(Kernel, Listen);
 	Error ->
 	    exit(Error)
diff --git a/lib/kernel/src/kernel.erl b/lib/kernel/src/kernel.erl
index 1e07620a3e..ecdb32424a 100644
--- a/lib/kernel/src/kernel.erl
+++ b/lib/kernel/src/kernel.erl
@@ -1,7 +1,7 @@
 %%
 %% %CopyrightBegin%
 %% 
-%% Copyright Ericsson AB 1996-2010. All Rights Reserved.
+%% Copyright Ericsson AB 1996-2013. All Rights Reserved.
 %% 
 %% The contents of this file are subject to the Erlang Public License,
 %% Version 1.1, (the "License"); you may not use this file except in
@@ -32,8 +32,13 @@ start(_, []) ->
     case supervisor:start_link({local, kernel_sup}, kernel, []) of
 	{ok, Pid} ->
 	    Type = get_error_logger_type(),
-	    error_logger:swap_handler(Type),
-	    {ok, Pid, []};
+            case error_logger:swap_handler(Type) of
+                ok -> {ok, Pid, []};
+                Error ->
+                    %% Not necessary since the node will crash anyway:
+                    exit(Pid, shutdown),
+                    Error
+            end;
 	Error -> Error
     end.
 
diff --git a/lib/kernel/src/kernel_config.erl b/lib/kernel/src/kernel_config.erl
index 48141cfa03..56defcb167 100644
--- a/lib/kernel/src/kernel_config.erl
+++ b/lib/kernel/src/kernel_config.erl
@@ -121,7 +121,7 @@ send_timeout(Timeout, Pid) ->
     end.
 
 wait_nodes(Mandatory, Optional) ->
-    net_kernel:monitor_nodes(true),
+    ok = net_kernel:monitor_nodes(true),
     lists:foreach(fun(Node) -> 
 		     case net_adm:ping(Node) of
 			 pong -> self() ! {nodeup, Node};
@@ -129,7 +129,9 @@ wait_nodes(Mandatory, Optional) ->
 		     end
 		  end,
 		  Mandatory ++ Optional),
-    rec_nodes(Mandatory, Optional).
+    R = rec_nodes(Mandatory, Optional),
+    ok = net_kernel:monitor_nodes(false),
+    R.
 
 rec_nodes([], []) -> ok;
 rec_nodes(Mandatory, Optional) ->
diff --git a/lib/kernel/src/net_adm.erl b/lib/kernel/src/net_adm.erl
index 9b2dac9544..3f5eac7822 100644
--- a/lib/kernel/src/net_adm.erl
+++ b/lib/kernel/src/net_adm.erl
@@ -1,7 +1,7 @@
 %%
 %% %CopyrightBegin%
 %% 
-%% Copyright Ericsson AB 1996-2011. All Rights Reserved.
+%% Copyright Ericsson AB 1996-2013. All Rights Reserved.
 %% 
 %% The contents of this file are subject to the Erlang Public License,
 %% Version 1.1, (the "License"); you may not use this file except in
@@ -133,7 +133,7 @@ dns_hostname(Hostname) ->
 -spec ping_list([atom()]) -> [atom()].
 
 ping_list(Nodelist) ->
-    net_kernel:monitor_nodes(true),
+    ok = net_kernel:monitor_nodes(true),
     Sofar = ping_first(Nodelist, nodes()),
     collect_new(Sofar, Nodelist).
 
@@ -159,7 +159,7 @@ collect_new(Sofar, Nodelist) ->
 		    collect_new([Node | Sofar], Nodelist)
 	    end
     after 3000 ->
-	    net_kernel:monitor_nodes(false),
+	    ok = net_kernel:monitor_nodes(false),
 	    Sofar
     end.
 
diff --git a/lib/kernel/src/net_kernel.erl b/lib/kernel/src/net_kernel.erl
index dd0071b914..04a0d94ebf 100644
--- a/lib/kernel/src/net_kernel.erl
+++ b/lib/kernel/src/net_kernel.erl
@@ -306,21 +306,21 @@ do_connect(Node, Type, WaitForBarred) -> %% Type = normal | hidden
     end.
 
 passive_connect_monitor(Parent, Node) ->
-    monitor_nodes(true,[{node_type,all}]),
+    ok = monitor_nodes(true,[{node_type,all}]),
     case lists:member(Node,nodes([connected])) of
 	true ->
-	    monitor_nodes(false,[{node_type,all}]),
+	    ok = monitor_nodes(false,[{node_type,all}]),
 	    Parent ! {self(),true};
 	_ ->
 	    Ref = make_ref(),
 	    Tref = erlang:send_after(connecttime(),self(),Ref),
 	    receive
 		Ref ->
-		    monitor_nodes(false,[{node_type,all}]),
+		    ok = monitor_nodes(false,[{node_type,all}]),
 		    Parent ! {self(), false};
 		{nodeup,Node,_} ->
-		    monitor_nodes(false,[{node_type,all}]),
-		    erlang:cancel_timer(Tref),
+		    ok = monitor_nodes(false,[{node_type,all}]),
+		    _ = erlang:cancel_timer(Tref),
 		    Parent ! {self(),true}
 	    end
     end.
@@ -734,7 +734,7 @@ handle_info(transition_period_end,
 				       how = How}} = State) ->
     ?tckr_dbg(transition_period_ended),
     case How of
-	shorter -> Tckr ! {new_ticktime, T};
+	shorter -> Tckr ! {new_ticktime, T}, done;
 	_       -> done
     end,
     {noreply,State#state{tick = #tick{ticker = Tckr, time = T}}};
@@ -1573,9 +1573,10 @@ async_gen_server_reply(From, Msg) ->
         ok ->
             ok;
         nosuspend ->
-            spawn(fun() -> catch erlang:send(Pid, M, [noconnect]) end);
+            _ = spawn(fun() -> catch erlang:send(Pid, M, [noconnect]) end),
+	    ok;
         noconnect ->
             ok; % The gen module takes care of this case.
-        {'EXIT', _}=EXIT ->
-            EXIT
+        {'EXIT', _} ->
+            ok
     end.
diff --git a/lib/kernel/src/os.erl b/lib/kernel/src/os.erl
index 742c000cc1..1f96e5c3c0 100644
--- a/lib/kernel/src/os.erl
+++ b/lib/kernel/src/os.erl
@@ -275,8 +275,8 @@ start_port_srv_handle({Ref,Client}) ->
 		error:Reason ->
 		    {Reason,erlang:get_stacktrace()}	    
 	    end,
-    Client ! {Ref,Reply}.
-
+    Client ! {Ref,Reply},
+    ok.
 
 start_port_srv_loop() ->
     receive
@@ -284,7 +284,7 @@ start_port_srv_loop() ->
 				     is_pid(Client) ->
 	    start_port_srv_handle(Request);
 	_Junk ->
-	    ignore
+	    ok
     end,
     start_port_srv_loop().
 
diff --git a/lib/kernel/src/pg2.erl b/lib/kernel/src/pg2.erl
index 1ff10eb303..b562d4ffd2 100644
--- a/lib/kernel/src/pg2.erl
+++ b/lib/kernel/src/pg2.erl
@@ -1,7 +1,7 @@
 %%
 %% %CopyrightBegin%
 %%
-%% Copyright Ericsson AB 1997-2012. All Rights Reserved.
+%% Copyright Ericsson AB 1997-2013. All Rights Reserved.
 %%
 %% The contents of this file are subject to the Erlang Public License,
 %% Version 1.1, (the "License"); you may not use this file except in
@@ -45,7 +45,7 @@ start() ->
 -spec create(Name :: name()) -> 'ok'.
 
 create(Name) ->
-    ensure_started(),
+    _ = ensure_started(),
     case ets:member(pg2_table, {group, Name}) of
         false ->
             global:trans({{?MODULE, Name}, self()},
@@ -60,7 +60,7 @@ create(Name) ->
 -spec delete(Name :: name()) -> 'ok'.
 
 delete(Name) ->
-    ensure_started(),
+    _ = ensure_started(),
     global:trans({{?MODULE, Name}, self()},
                  fun() ->
                          gen_server:multi_call(?MODULE, {delete, Name})
@@ -71,7 +71,7 @@ delete(Name) ->
       when Name :: name().
 
 join(Name, Pid) when is_pid(Pid) ->
-    ensure_started(),
+    _ = ensure_started(),
     case ets:member(pg2_table, {group, Name}) of
         false ->
             {error, {no_such_group, Name}};
@@ -88,7 +88,7 @@ join(Name, Pid) when is_pid(Pid) ->
       when Name :: name().
 
 leave(Name, Pid) when is_pid(Pid) ->
-    ensure_started(),
+    _ = ensure_started(),
     case ets:member(pg2_table, {group, Name}) of
         false ->
             {error, {no_such_group, Name}};
@@ -105,7 +105,7 @@ leave(Name, Pid) when is_pid(Pid) ->
       when Name :: name().
 
 get_members(Name) ->
-    ensure_started(),
+    _ = ensure_started(),
     case ets:member(pg2_table, {group, Name}) of
         true ->
             group_members(Name);
@@ -117,7 +117,7 @@ get_members(Name) ->
       when Name :: name().
 
 get_local_members(Name) ->
-    ensure_started(),
+    _ = ensure_started(),
     case ets:member(pg2_table, {group, Name}) of
         true ->
             local_group_members(Name);
@@ -128,7 +128,7 @@ get_local_members(Name) ->
 -spec which_groups() -> [Name :: name()].
 
 which_groups() ->
-    ensure_started(),
+    _ = ensure_started(),
     all_groups().
 
 -spec get_closest_pid(Name) ->  pid() | {'error', Reason} when
@@ -165,7 +165,7 @@ get_closest_pid(Name) ->
 
 init([]) ->
     Ns = nodes(),
-    net_kernel:monitor_nodes(true),
+    ok = net_kernel:monitor_nodes(true),
     lists:foreach(fun(N) ->
                           {?MODULE, N} ! {new_pg2, node()},
                           self() ! {nodeup, N}
@@ -283,7 +283,7 @@ member_died(Ref) ->
 
 join_group(Name, Pid) ->
     Ref_Pid = {ref, Pid}, 
-    try _ = ets:update_counter(pg2_table, Ref_Pid, {4, +1})
+    try _ = ets:update_counter(pg2_table, Ref_Pid, {4, +1}), true
     catch _:_ ->
             {RPid, Ref} = do_monitor(Pid),
             true = ets:insert(pg2_table, {Ref_Pid, RPid, Ref, 1}),
diff --git a/lib/kernel/src/rpc.erl b/lib/kernel/src/rpc.erl
index 83e0b59cc2..78fec2aa2b 100644
--- a/lib/kernel/src/rpc.erl
+++ b/lib/kernel/src/rpc.erl
@@ -1,7 +1,7 @@
 %%
 %% %CopyrightBegin%
 %%
-%% Copyright Ericsson AB 1996-2012. All Rights Reserved.
+%% Copyright Ericsson AB 1996-2013. All Rights Reserved.
 %%
 %% The contents of this file are subject to the Erlang Public License,
 %% Version 1.1, (the "License"); you may not use this file except in
@@ -158,20 +158,20 @@ handle_info({Caller, {reply, Reply}}, S) ->
 	    {noreply, S}
     end;
 handle_info({From, {sbcast, Name, Msg}}, S) ->
-    case catch Name ! Msg of  %% use catch to get the printout
-	{'EXIT', _} ->
-	    From ! {?NAME, node(), {nonexisting_name, Name}};
-	_ -> 
-	    From ! {?NAME, node(), node()}
-    end,
+    _ = case catch Name ! Msg of  %% use catch to get the printout
+            {'EXIT', _} ->
+                From ! {?NAME, node(), {nonexisting_name, Name}};
+            _ ->
+                From ! {?NAME, node(), node()}
+        end,
     {noreply, S};
 handle_info({From, {send, Name, Msg}}, S) ->
-    case catch Name ! {From, Msg} of %% use catch to get the printout
-	{'EXIT', _} ->
-	    From ! {?NAME, node(), {nonexisting_name, Name}};
-	_ ->
-	    ok    %% It's up to Name to respond !!!!!
-    end,
+    _ = case catch Name ! {From, Msg} of %% use catch to get the printout
+            {'EXIT', _} ->
+                From ! {?NAME, node(), {nonexisting_name, Name}};
+            _ ->
+                ok    %% It's up to Name to respond !!!!!
+        end,
     {noreply, S};
 handle_info({From, {call,Mod,Fun,Args,Gleader}}, S) ->
     %% Special for hidden C node's, uugh ...
@@ -423,7 +423,7 @@ abcast(Name, Mess) ->
 abcast([Node|Tail], Name, Mess) ->
     Dest = {Name,Node},
     case catch erlang:send(Dest, Mess, [noconnect]) of
-	noconnect -> spawn(erlang, send, [Dest,Mess]);
+	noconnect -> spawn(erlang, send, [Dest,Mess]), ok;
 	_ -> ok
     end,
     abcast(Tail, Name, Mess);
diff --git a/lib/kernel/src/seq_trace.erl b/lib/kernel/src/seq_trace.erl
index a90b7b07c8..38a61f4644 100644
--- a/lib/kernel/src/seq_trace.erl
+++ b/lib/kernel/src/seq_trace.erl
@@ -1,7 +1,7 @@
 %%
 %% %CopyrightBegin%
 %% 
-%% Copyright Ericsson AB 1998-2011. All Rights Reserved.
+%% Copyright Ericsson AB 1998-2013. All Rights Reserved.
 %% 
 %% The contents of this file are subject to the Erlang Public License,
 %% Version 1.1, (the "License"); you may not use this file except in
@@ -125,7 +125,7 @@ get_system_tracer() ->
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 
 set_token2([{Type,Val}|T]) ->
-    erlang:seq_trace(Type, Val),
+    _ = erlang:seq_trace(Type, Val),
     set_token2(T);
 set_token2([]) ->
     ok.
diff --git a/lib/kernel/src/standard_error.erl b/lib/kernel/src/standard_error.erl
index e41dcd01fc..10cf77e0d4 100644
--- a/lib/kernel/src/standard_error.erl
+++ b/lib/kernel/src/standard_error.erl
@@ -1,7 +1,7 @@
 %%
 %% %CopyrightBegin%
 %%
-%% Copyright Ericsson AB 2009-2010. All Rights Reserved.
+%% Copyright Ericsson AB 2009-2013. All Rights Reserved.
 %%
 %% The contents of this file are subject to the Erlang Public License,
 %% Version 1.1, (the "License"); you may not use this file except in
@@ -69,7 +69,7 @@ run(P) ->
 server_loop(Port) ->
     receive
 	{io_request,From,ReplyAs,Request} when is_pid(From) ->
-	    do_io_request(Request, From, ReplyAs, Port),
+	    _ = do_io_request(Request, From, ReplyAs, Port),
 	    server_loop(Port);
 	{'EXIT',Port,badsig} ->			% Ignore badsig errors
 	    server_loop(Port);
@@ -175,7 +175,7 @@ io_reply(From, ReplyAs, Reply) ->
 
 %% put_chars
 put_chars(Chars, Port) when is_binary(Chars) ->
-    put_port(Chars, Port),
+    _ = put_port(Chars, Port),
     {ok,ok};
 put_chars(Chars, Port) ->
     case catch list_to_binary(Chars) of
diff --git a/lib/kernel/src/user.erl b/lib/kernel/src/user.erl
index c897d46bc2..40376ef752 100644
--- a/lib/kernel/src/user.erl
+++ b/lib/kernel/src/user.erl
@@ -103,11 +103,11 @@ catch_loop(Port, Shell, Q) ->
 	{unknown_exit,{Shell,Reason},_} ->		 % shell has exited
 	    case Reason of
 		normal ->
-		    put_chars("*** ", Port, []);
+                    put_port(<<"*** ">>, Port);
 		_ ->
-		    put_chars("*** ERROR: ", Port, [])
+                    put_port(<<"*** ERROR: ">>, Port)
 	    end,
-	    put_chars("Shell process terminated! ***\n", Port, []),
+	    put_port(<<"Shell process terminated! ***\n">>, Port),
 	    catch_loop(Port, start_new_shell());
 	{unknown_exit,_,Q1} ->
 	    catch_loop(Port, Shell, Q1);	     
@@ -181,7 +181,7 @@ get_fd_geometry(Port) ->
 do_io_request(Req, From, ReplyAs, Port, Q0) ->
     case io_request(Req, Port, Q0) of
 	{_Status,Reply,Q1} ->
-	    io_reply(From, ReplyAs, Reply),
+	    _ = io_reply(From, ReplyAs, Reply),
 	    Q1;
 	{exit,What} ->
 	    ok = send_port(Port, close),
diff --git a/lib/kernel/src/user_drv.erl b/lib/kernel/src/user_drv.erl
index bb654495d3..6544426a54 100644
--- a/lib/kernel/src/user_drv.erl
+++ b/lib/kernel/src/user_drv.erl
@@ -488,21 +488,19 @@ set_unicode_state(Iport, Bool) ->
 
 %% io_request(Request, InPort, OutPort)
 %% io_requests(Requests, InPort, OutPort)
-
-io_request({put_chars, unicode,Cs}, _Iport, Oport) ->
-    Oport ! {self(),{command,[?OP_PUTC|unicode:characters_to_binary(Cs,utf8)]}};
-io_request({move_rel,N}, _Iport, Oport) ->
-    Oport ! {self(),{command,[?OP_MOVE|put_int16(N, [])]}};
-io_request({insert_chars,unicode,Cs}, _Iport, Oport) ->
-    Oport ! {self(),{command,[?OP_INSC|unicode:characters_to_binary(Cs,utf8)]}};
-io_request({delete_chars,N}, _Iport, Oport) ->
-    Oport ! {self(),{command,[?OP_DELC|put_int16(N, [])]}};
-io_request(beep, _Iport, Oport) ->
-    Oport ! {self(),{command,[?OP_BEEP]}};
-io_request({requests,Rs}, Iport, Oport) ->
-    io_requests(Rs, Iport, Oport);
-io_request(_R, _Iport, _Oport) ->
-    ok.
+%% Note: InPort is unused.
+
+io_request(Request, Iport, Oport) ->
+    try io_command(Request) of
+        Command ->
+            Oport ! {self(),Command},
+            ok
+    catch
+        {requests,Rs} ->
+            io_requests(Rs, Iport, Oport);
+        _ ->
+            ok
+    end.
 
 io_requests([R|Rs], Iport, Oport) ->
     io_request(R, Iport, Oport),
@@ -513,6 +511,19 @@ io_requests([], _Iport, _Oport) ->
 put_int16(N, Tail) ->
     [(N bsr 8)band 255,N band 255|Tail].
 
+io_command({put_chars, unicode,Cs}) ->
+    {command,[?OP_PUTC|unicode:characters_to_binary(Cs,utf8)]};
+io_command({move_rel,N}) ->
+    {command,[?OP_MOVE|put_int16(N, [])]};
+io_command({insert_chars,unicode,Cs}) ->
+    {command,[?OP_INSC|unicode:characters_to_binary(Cs,utf8)]};
+io_command({delete_chars,N}) ->
+    {command,[?OP_DELC|put_int16(N, [])]};
+io_command(beep) ->
+    {command,[?OP_BEEP]};
+io_command(Else) ->
+    throw(Else).
+
 %% gr_new()
 %% gr_get_num(Group, Index)
 %% gr_get_info(Group, Pid)
diff --git a/lib/kernel/src/wrap_log_reader.erl b/lib/kernel/src/wrap_log_reader.erl
index 689269fc28..7e1f4aa07f 100644
--- a/lib/kernel/src/wrap_log_reader.erl
+++ b/lib/kernel/src/wrap_log_reader.erl
@@ -1,7 +1,7 @@
 %%
 %% %CopyrightBegin%
 %%
-%% Copyright Ericsson AB 1998-2012. All Rights Reserved.
+%% Copyright Ericsson AB 1998-2013. All Rights Reserved.
 %%
 %% The contents of this file are subject to the Erlang Public License,
 %% Version 1.1, (the "License"); you may not use this file except in
@@ -149,7 +149,7 @@ open_int(File, FileNo, FirstFileNo) ->
 		{ok, Head} ->
 		    case disk_log_1:is_head(Head) of
 			no ->
-			    file:close(Fd),
+			    _ = file:close(Fd),
 			    {error, {not_a_log_file, FName}};
 			_ -> % yes or yes_not_closed
 			    case last_mod_time(FName) of
@@ -161,12 +161,12 @@ open_int(File, FileNo, FirstFileNo) ->
 						      first_no = FirstFileNo},
 				    {ok, WR};
 				{error, E} ->
-				    file:close(Fd),
+				    _ = file:close(Fd),
 				    {error, {file_error, FName, E}}
 			    end
 		    end;
 		_Other ->
-		    file:close(Fd),
+		    _ = file:close(Fd),
 		    {error, {not_a_log_file, FName}}
 	    end;
 	_Other ->
@@ -280,7 +280,7 @@ read_next_file(WR, N, NewFileNo, Bad) ->
 		true -> 
 		    case open_int(File, NewFileNo, FirstFileNo) of
 			{ok, NWR} ->
-			    close(WR), %% Now we can safely close the old file.
+			    _ = close(WR), %% Now we can safely close the old file.
 			    chunk(NWR, N, Bad);
 			Error ->
 			    Error