Merge branch 'bjorn/ct/separate-io-server/OTP-10101'

* bjorn/ct/separate-io-server/OTP-10101:
  Test ct:capture/start/stop/get
  Introduce ct_group_leader_SUITE that does nasty things with group leaders
  Eliminate unexpected I/O to the minor log file
  Introduce test_server_io and test_server_gl
  Clean up initialization of parallel test cases
  Introduce is_io_buffered/0 to somewhat improve readability
  test_server_ctrl: Consistently use set_io_buffering/1

6 files changed, 823 insertions, 457 deletions

diff --git a/lib/test_server/src/Makefile b/lib/test_server/src/Makefile
index bb0b4e55b8..20e7a5942c 100644
--- a/lib/test_server/src/Makefile
+++ b/lib/test_server/src/Makefile
@@ -40,6 +40,8 @@ RELSYSDIR = $(RELEASE_PATH)/lib/test_server-$(VSN)
 # ----------------------------------------------------
 
 MODULES= test_server_ctrl \
+	 test_server_gl \
+	 test_server_io \
 	 test_server_node \
 	 test_server \
 	 test_server_sup \
diff --git a/lib/test_server/src/test_server.app.src b/lib/test_server/src/test_server.app.src
index faf7db835e..26330f9695 100644
--- a/lib/test_server/src/test_server.app.src
+++ b/lib/test_server/src/test_server.app.src
@@ -24,6 +24,7 @@
 	     test_server_ctrl,
 	     test_server,
 	     test_server_h,
+	     test_server_io,
 	     test_server_node,
 	     test_server_sup
 	    ]},
diff --git a/lib/test_server/src/test_server.erl b/lib/test_server/src/test_server.erl
index bfa5e927b1..bcffe896c4 100644
--- a/lib/test_server/src/test_server.erl
+++ b/lib/test_server/src/test_server.erl
@@ -524,7 +524,7 @@ stick_all_sticky(Node,Sticky) ->
 
 
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
-%% run_test_case_apply(Mod,Func,Args,Name,RunInit,TimetrapData,RejectIoReqs) ->
+%% run_test_case_apply(Mod,Func,Args,Name,RunInit,TimetrapData) ->
 %%               {Time,Value,Loc,Opts,Comment} | {died,Reason,unknown,Comment}
 %%
 %% Time = float()   (seconds)
@@ -538,7 +538,6 @@ stick_all_sticky(Node,Sticky) ->
 %% it possible to capture all it's output from io:format/2, etc.
 %%
 %% The job process then sits down and waits for news from the case process.
-%% This might be io requests (which are redirected to the log files).
 %%
 %% Returns a tuple with the time spent (in seconds) in the test case,
 %% the return value from the test case or an {'EXIT',Reason} if the case
@@ -559,12 +558,9 @@ stick_all_sticky(Node,Sticky) ->
 %% ScaleTimetrap indicates if test_server should attemp to automatically
 %% compensate timetraps for runtime delays introduced by e.g. tools like
 %% cover.
-%% 
-%% RejectIoReqs (bool) is information about whether printouts to stdout
-%% should be visible in the minor log file or not.
 
 run_test_case_apply({CaseNum,Mod,Func,Args,Name,
-		     RunInit,TimetrapData,RejectIoReqs}) ->
+		     RunInit,TimetrapData}) ->
     purify_format("Test case #~w ~w:~w/1", [CaseNum, Mod, Func]),
     case os:getenv("TS_RUN_VALGRIND") of
 	false ->
@@ -576,18 +572,18 @@ run_test_case_apply({CaseNum,Mod,Func,Args,Name,
     test_server_h:testcase({Mod,Func,1}),
     ProcBef = erlang:system_info(process_count),
     Result = run_test_case_apply(Mod, Func, Args, Name, RunInit,
-				 TimetrapData, RejectIoReqs),
+				 TimetrapData),
     ProcAft = erlang:system_info(process_count),
     purify_new_leaks(),
     DetFail = get(test_server_detected_fail),
     {Result,DetFail,ProcBef,ProcAft}.
 
-run_test_case_apply(Mod, Func, Args, Name, RunInit, TimetrapData, RejectIoReqs) ->
+run_test_case_apply(Mod, Func, Args, Name, RunInit, TimetrapData) ->
     case get(test_server_job_dir) of
 	undefined ->
 	    %% i'm a local target
 	    do_run_test_case_apply(Mod, Func, Args, Name, RunInit,
-				   TimetrapData, RejectIoReqs);
+				   TimetrapData);
 	JobDir ->
 	    %% i'm a remote target
 	    case Args of
@@ -602,14 +598,14 @@ run_test_case_apply(Mod, Func, Args, Name, RunInit, TimetrapData, RejectIoReqs)
 		    Config2 = lists:keyreplace(priv_dir, 1, Config1,
 					       {priv_dir,TargetPrivDir}),
 		    do_run_test_case_apply(Mod, Func, [Config2], Name, RunInit,
-					   TimetrapData, RejectIoReqs);
+					   TimetrapData);
 		_other ->
 		    do_run_test_case_apply(Mod, Func, Args, Name, RunInit,
-					   TimetrapData, RejectIoReqs)
+					   TimetrapData)
 	    end
     end.
-do_run_test_case_apply(Mod, Func, Args, Name, RunInit,
-		       TimetrapData, RejectIoReqs) ->
+
+do_run_test_case_apply(Mod, Func, Args, Name, RunInit, TimetrapData) ->
     {ok,Cwd} = file:get_cwd(),
     Args2Print = case Args of
 		     [Args1] when is_list(Args1) ->
@@ -624,9 +620,6 @@ do_run_test_case_apply(Mod, Func, Args, Name, RunInit,
     TCCallback = get(test_server_testcase_callback),
     LogOpts = get(test_server_logopts),
     Ref = make_ref(),
-    OldGLeader = group_leader(),
-    %% Set ourself to group leader for the spawned process
-    group_leader(self(),self()),
     Pid =
 	spawn_link(
 	  fun() ->
@@ -634,9 +627,8 @@ do_run_test_case_apply(Mod, Func, Args, Name, RunInit,
 				     RunInit, TimetrapData,
 				     LogOpts, TCCallback)
 	  end),
-    group_leader(OldGLeader, self()),
     put(test_server_detected_fail, []),
-    run_test_case_msgloop(Ref, Pid, false, RejectIoReqs, false, "",
+    run_test_case_msgloop(Ref, Pid, false, "",
 			  undefined, starting).
 
 %% Ugly bug (pre R5A):
@@ -648,8 +640,7 @@ do_run_test_case_apply(Mod, Func, Args, Name, RunInit,
 %% A test case is known to have failed if it returns {'EXIT', _} tuple,
 %% or sends a message {failed, File, Line} to it's group_leader
 %%
-run_test_case_msgloop(Ref, Pid, CaptureStdout, RejectIoReqs, Terminate,
-		      Comment, CurrConf, Status) ->
+run_test_case_msgloop(Ref, Pid, Terminate, Comment, CurrConf, Status) ->
     %% NOTE: Keep job_proxy_msgloop/0 up to date when changes
     %%       are made in this function!
     {Timeout,ReturnValue} =
@@ -664,7 +655,7 @@ run_test_case_msgloop(Ref, Pid, CaptureStdout, RejectIoReqs, Terminate,
 	end,
     receive
 	{test_case_initialized,Pid} ->
-	    run_test_case_msgloop(Ref,Pid,CaptureStdout,RejectIoReqs,Terminate,
+	    run_test_case_msgloop(Ref,Pid,Terminate,
 				  Comment,CurrConf,running);
 	Abort = {abort_current_testcase,_,_} when Status == starting ->
 	    %% we're in init phase, must must postpone this operation
@@ -672,7 +663,7 @@ run_test_case_msgloop(Ref, Pid, CaptureStdout, RejectIoReqs, Terminate,
 	    %% gets killed)
 	    self() ! Abort,
 	    erlang:yield(),
-	    run_test_case_msgloop(Ref,Pid,CaptureStdout,RejectIoReqs,Terminate,
+	    run_test_case_msgloop(Ref,Pid,Terminate,
 				  Comment,CurrConf,Status);
 	{abort_current_testcase,Reason,From} ->
 	    Line = case is_process_alive(Pid) of
@@ -703,92 +694,15 @@ run_test_case_msgloop(Ref, Pid, CaptureStdout, RejectIoReqs, Terminate,
 				    Error1
 			    end
 		    end,
-	    run_test_case_msgloop(Ref,Pid,CaptureStdout,RejectIoReqs,Terminate,
+	    run_test_case_msgloop(Ref,Pid,Terminate,
 				  NewComment,CurrConf,Status);
-	{permit_io,FromPid} ->
-	    put({permit_io,FromPid},true),
-	    run_test_case_msgloop(Ref,Pid,CaptureStdout,RejectIoReqs,Terminate,
-				  Comment,CurrConf,Status);
-        {io_request,From,ReplyAs,{put_chars,io_lib,Func,[Format,Args]}}
-	when is_list(Format) ->
-	    Msg = (catch io_lib:Func(Format,Args)),
-	    run_test_case_msgloop_io(From,ReplyAs,CaptureStdout,RejectIoReqs,
-				     Msg,From,Func),
-            run_test_case_msgloop(Ref,Pid,CaptureStdout,RejectIoReqs,Terminate,
-				  Comment,CurrConf,Status);
-        {io_request,From,ReplyAs,{put_chars,io_lib,Func,[Format,Args]}}
-	when is_atom(Format) ->
-	    Msg = (catch io_lib:Func(Format,Args)),
-	    run_test_case_msgloop_io(From,ReplyAs,CaptureStdout,RejectIoReqs,
-				     Msg,From,Func),
-            run_test_case_msgloop(Ref,Pid,CaptureStdout,RejectIoReqs,Terminate,
-				  Comment,CurrConf,Status);
-        {io_request,From,ReplyAs,{put_chars,Bytes}} ->
-	    run_test_case_msgloop_io(From,ReplyAs,CaptureStdout,RejectIoReqs,
-				     Bytes,From,put_chars),
-            run_test_case_msgloop(Ref,Pid,CaptureStdout,RejectIoReqs,Terminate,
-				  Comment,CurrConf,Status);
-        {io_request,From,ReplyAs,{put_chars,unicode,io_lib,Func,[Format,Args]}}
-	when is_list(Format) ->
-	    Msg = unicode_to_latin1(catch io_lib:Func(Format,Args)),
-	    run_test_case_msgloop_io(From,ReplyAs,CaptureStdout,RejectIoReqs,
-				     Msg,From,Func),
-            run_test_case_msgloop(Ref,Pid,CaptureStdout,RejectIoReqs,Terminate,
-				  Comment,CurrConf,Status);
-        {io_request,From,ReplyAs,{put_chars,latin1,io_lib,Func,[Format,Args]}}
-	when is_list(Format) ->
-	    Msg = (catch io_lib:Func(Format,Args)),
-	    run_test_case_msgloop_io(From,ReplyAs,CaptureStdout,RejectIoReqs,
-				     Msg,From,Func),
-            run_test_case_msgloop(Ref,Pid,CaptureStdout,RejectIoReqs,Terminate,
-				  Comment,CurrConf,Status);
-        {io_request,From,ReplyAs,{put_chars,unicode,io_lib,Func,[Format,Args]}}
-	when is_atom(Format) ->
-	    Msg = unicode_to_latin1(catch io_lib:Func(Format,Args)),
-	    run_test_case_msgloop_io(From,ReplyAs,CaptureStdout,RejectIoReqs,
-				     Msg,From,Func),
-            run_test_case_msgloop(Ref,Pid,CaptureStdout,RejectIoReqs,Terminate,
-				  Comment,CurrConf,Status);
-        {io_request,From,ReplyAs,{put_chars,latin1,io_lib,Func,[Format,Args]}}
-	when is_atom(Format) ->
-	    Msg = (catch io_lib:Func(Format,Args)),
-	    run_test_case_msgloop_io(From,ReplyAs,CaptureStdout,RejectIoReqs,
-				     Msg,From,Func),
-            run_test_case_msgloop(Ref,Pid,CaptureStdout,RejectIoReqs,Terminate,
-				  Comment,CurrConf,Status);
-        {io_request,From,ReplyAs,{put_chars,unicode,Bytes}} ->
-	    run_test_case_msgloop_io(From,ReplyAs,CaptureStdout,RejectIoReqs,
-				     unicode_to_latin1(Bytes),From,put_chars),
-            run_test_case_msgloop(Ref,Pid,CaptureStdout,RejectIoReqs,Terminate,
-				  Comment,CurrConf,Status);
-        {io_request,From,ReplyAs,{put_chars,latin1,Bytes}} ->
-	    run_test_case_msgloop_io(From,ReplyAs,CaptureStdout,RejectIoReqs,
-				     Bytes,From,put_chars),
-            run_test_case_msgloop(Ref,Pid,CaptureStdout,RejectIoReqs,Terminate,
-				  Comment,CurrConf,Status);
-        IoReq when element(1, IoReq) == io_request ->
-	    %% something else, just pass it on
-            group_leader() ! IoReq,
-            run_test_case_msgloop(Ref,Pid,CaptureStdout,RejectIoReqs,Terminate,
-				  Comment,CurrConf,Status);
-	{structured_io,ClientPid,Msg} ->
-	    output(Msg, ClientPid),
-            run_test_case_msgloop(Ref,Pid,CaptureStdout,RejectIoReqs,Terminate,
-				  Comment,CurrConf,Status);
-	{capture,NewCapture} ->
-            run_test_case_msgloop(Ref,Pid,NewCapture,RejectIoReqs,Terminate,
-				  Comment,CurrConf,Status);
 	{sync_apply,From,MFA} ->
 	    sync_local_or_remote_apply(false,From,MFA),
-	    run_test_case_msgloop(Ref,Pid,CaptureStdout,RejectIoReqs,Terminate,
+	    run_test_case_msgloop(Ref,Pid,Terminate,
 				  Comment,CurrConf,Status);
 	{sync_apply_proxy,Proxy,From,MFA} ->
 	    sync_local_or_remote_apply(Proxy,From,MFA),
-	    run_test_case_msgloop(Ref,Pid,CaptureStdout,RejectIoReqs,Terminate,
-				  Comment,CurrConf,Status);
-	{printout,Detail,Format,Args} ->
-	    print(Detail,Format,Args),
-	    run_test_case_msgloop(Ref,Pid,CaptureStdout,RejectIoReqs,Terminate,
+	    run_test_case_msgloop(Ref,Pid,Terminate,
 				  Comment,CurrConf,Status);
 	{comment,NewComment} ->
 	    NewComment1 = test_server_ctrl:to_string(NewComment),
@@ -802,19 +716,19 @@ run_test_case_msgloop(Ref, Pid, CaptureStdout, RejectIoReqs, Terminate,
 		    Other ->
 			Other
 		end,
-	    run_test_case_msgloop(Ref,Pid,CaptureStdout,RejectIoReqs,Terminate1,
+	    run_test_case_msgloop(Ref,Pid,Terminate1,
 				  NewComment2,CurrConf,Status);
 	{read_comment,From} ->
 	    From ! {self(),read_comment,Comment},
-	    run_test_case_msgloop(Ref,Pid,CaptureStdout,RejectIoReqs,Terminate,
+	    run_test_case_msgloop(Ref,Pid,Terminate,
 				  Comment,CurrConf,Status);
 	{set_curr_conf,From,NewCurrConf} ->
 	    From ! {self(),set_curr_conf,ok},
-	    run_test_case_msgloop(Ref,Pid,CaptureStdout,RejectIoReqs,Terminate,
+	    run_test_case_msgloop(Ref,Pid,Terminate,
 				  Comment,NewCurrConf,Status);
 	{make_priv_dir,From} when CurrConf == undefined ->
 	    From ! {self(),make_priv_dir,{error,no_priv_dir_in_config}},
-	    run_test_case_msgloop(Ref,Pid,CaptureStdout,RejectIoReqs,Terminate,
+	    run_test_case_msgloop(Ref,Pid,Terminate,
 				  Comment,CurrConf,Status);
 	{make_priv_dir,From} ->
 	    Result =
@@ -832,11 +746,11 @@ run_test_case_msgloop(Ref, Pid, CaptureStdout, RejectIoReqs, Terminate,
 			end
 		end,
 	    From ! {self(),make_priv_dir,Result},
-	    run_test_case_msgloop(Ref,Pid,CaptureStdout,RejectIoReqs,Terminate,
+	    run_test_case_msgloop(Ref,Pid,Terminate,
 				  Comment,CurrConf,Status);
 	{'EXIT',Pid,{Ref,Time,Value,Loc,Opts}} ->
 	    RetVal = {Time/1000000,Value,mod_loc(Loc),Opts,Comment},
-	    run_test_case_msgloop(Ref,Pid,CaptureStdout,RejectIoReqs,
+	    run_test_case_msgloop(Ref,Pid,
 				  {true,RetVal},Comment,undefined,Status);
 	{'EXIT',Pid,Reason} ->
 	    case Reason of
@@ -849,7 +763,6 @@ run_test_case_msgloop(Ref, Pid, CaptureStdout, RejectIoReqs, Terminate,
 					  {framework_error,{timetrap,TVal}},
 					  unknown,self()),
 			    run_test_case_msgloop(Ref,Pid,
-						  CaptureStdout,RejectIoReqs,
 						  Terminate,Comment,
 						  undefined,Status);
 			Loc1 ->
@@ -883,7 +796,6 @@ run_test_case_msgloop(Ref, Pid, CaptureStdout, RejectIoReqs, Terminate,
 					undefined
 				end,
 			    run_test_case_msgloop(Ref,Pid,
-						  CaptureStdout,RejectIoReqs,
 						  Terminate,Comment,
 						  NewCurrConf,Status)
 		    end;
@@ -900,7 +812,7 @@ run_test_case_msgloop(Ref, Pid, CaptureStdout, RejectIoReqs, Terminate,
 					  {timetrap_timeout,TVal},
 					  Loc1,self())
 		    end,
-		    run_test_case_msgloop(Ref,Pid,CaptureStdout,RejectIoReqs,
+		    run_test_case_msgloop(Ref,Pid,
 					  Terminate,Comment,CurrConf,Status);
 		{testcase_aborted,ErrorMsg={user_timetrap_error,_},AbortLoc} ->
 		    %% user timetrap function caused exit
@@ -909,7 +821,6 @@ run_test_case_msgloop(Ref, Pid, CaptureStdout, RejectIoReqs, Terminate,
 		    spawn_fw_call(Mod,Func,CurrConf,Pid,
 				  ErrorMsg,unknown,self()),
 		    run_test_case_msgloop(Ref,Pid,
-					  CaptureStdout,RejectIoReqs,
 					  Terminate,Comment,
 					  undefined,Status);		
 		{testcase_aborted,AbortReason,AbortLoc} ->
@@ -921,7 +832,6 @@ run_test_case_msgloop(Ref, Pid, CaptureStdout, RejectIoReqs, Terminate,
 					  {framework_error,ErrorMsg},
 					  unknown,self()),
 			    run_test_case_msgloop(Ref,Pid,
-						  CaptureStdout,RejectIoReqs,
 						  Terminate,Comment,
 						  undefined,Status);
 			Loc1 ->
@@ -954,7 +864,6 @@ run_test_case_msgloop(Ref, Pid, CaptureStdout, RejectIoReqs, Terminate,
 					undefined
 				end,
 			    run_test_case_msgloop(Ref,Pid,
-						  CaptureStdout,RejectIoReqs,
 						  Terminate,Comment,
 						  NewCurrConf,Status)
 		    end;
@@ -969,13 +878,13 @@ run_test_case_msgloop(Ref, Pid, CaptureStdout, RejectIoReqs, Terminate,
 		    spawn_fw_call(Mod,Func,CurrConf,Pid,
 				  testcase_aborted_or_killed,
 				  unknown,self()),
-		    run_test_case_msgloop(Ref,Pid,CaptureStdout,RejectIoReqs,
+		    run_test_case_msgloop(Ref,Pid,
 					  Terminate,Comment,CurrConf,Status);
 		{fw_error,{FwMod,FwFunc,FwError}} ->
 		    spawn_fw_call(FwMod,FwFunc,CurrConf,Pid,
 				  {framework_error,FwError},
 				  unknown,self()),
-		    run_test_case_msgloop(Ref,Pid,CaptureStdout,RejectIoReqs,
+		    run_test_case_msgloop(Ref,Pid,
 					  Terminate,Comment,CurrConf,Status);
 		_Other ->
 		    %% the testcase has terminated because of Reason (e.g. an exit
@@ -986,7 +895,7 @@ run_test_case_msgloop(Ref, Pid, CaptureStdout, RejectIoReqs, Terminate,
 				 end,
 		    spawn_fw_call(Mod,Func,CurrConf,Pid,
 				  Reason,unknown,self()),
-		    run_test_case_msgloop(Ref,Pid,CaptureStdout,RejectIoReqs,
+		    run_test_case_msgloop(Ref,Pid,
 					  Terminate,Comment,CurrConf,Status)
 	    end;
 	{EndConfPid,{call_end_conf,Data,_Result}} ->
@@ -995,10 +904,10 @@ run_test_case_msgloop(Ref, Pid, CaptureStdout, RejectIoReqs, Terminate,
 		    {_Mod,_Func,TCPid,TCExitReason,Loc} = Data,
 		    spawn_fw_call(Mod,Func,CurrConf,TCPid,
 				  TCExitReason,Loc,self()),
-		    run_test_case_msgloop(Ref,Pid,CaptureStdout,RejectIoReqs,
+		    run_test_case_msgloop(Ref,Pid,
 					  Terminate,Comment,undefined,Status);
 		_ ->
-		    run_test_case_msgloop(Ref,Pid,CaptureStdout,RejectIoReqs,
+		    run_test_case_msgloop(Ref,Pid,
 					  Terminate,Comment,CurrConf,Status)
 	    end;
 	{_FwCallPid,fw_notify_done,{T,Value,Loc,Opts,AddToComment}} ->
@@ -1019,7 +928,7 @@ run_test_case_msgloop(Ref, Pid, CaptureStdout, RejectIoReqs, Terminate,
 			    end,
 			{T,Value,Loc,Opts,Comment1}
 		end,
-	    run_test_case_msgloop(Ref,Pid,CaptureStdout,RejectIoReqs,
+	    run_test_case_msgloop(Ref,Pid,
 				  {true,RetVal},Comment,undefined,Status);
  	{'EXIT',_FwCallPid,{fw_notify_done,Func,Error}} ->
 	    %% a framework function failed
@@ -1031,12 +940,12 @@ run_test_case_msgloop(Ref, Pid, CaptureStdout, RejectIoReqs, Terminate,
 			  {list_to_atom(CB),Func}
 		  end,
 	    RetVal = {died,{framework_error,Loc,Error},Loc,"Framework error"},
-	    run_test_case_msgloop(Ref,Pid,CaptureStdout,RejectIoReqs,
+	    run_test_case_msgloop(Ref,Pid,
 				  {true,RetVal},Comment,undefined,Status);
 	{failed,File,Line} ->
 	    put(test_server_detected_fail,
 		[{File, Line}| get(test_server_detected_fail)]),
-	    run_test_case_msgloop(Ref,Pid,CaptureStdout,RejectIoReqs,
+	    run_test_case_msgloop(Ref,Pid,
 				  Terminate,Comment,CurrConf,Status);
 
 	{user_timetrap,Pid,_TrapTime,StartTime,E={user_timetrap_error,_},_} ->
@@ -1046,7 +955,7 @@ run_test_case_msgloop(Ref, Pid, CaptureStdout, RejectIoReqs, Terminate,
 		ignore ->
 		    ok
 	    end,
-	    run_test_case_msgloop(Ref,Pid,CaptureStdout,RejectIoReqs,
+	    run_test_case_msgloop(Ref,Pid,
 				  Terminate,Comment,CurrConf,Status);
 	{user_timetrap,Pid,TrapTime,StartTime,ElapsedTime,Scale} ->
 	    %% a user timetrap is triggered, ignore it if new
@@ -1062,68 +971,41 @@ run_test_case_msgloop(Ref, Pid, CaptureStdout, RejectIoReqs, Terminate,
 		ignore ->
 		    ok
 	    end,
-	    run_test_case_msgloop(Ref,Pid,CaptureStdout,RejectIoReqs,
+	    run_test_case_msgloop(Ref,Pid,
 				  Terminate,Comment,CurrConf,Status);
 	{timetrap_cancel_one,Handle,_From} ->
 	    timetrap_cancel_one(Handle, false),
-	    run_test_case_msgloop(Ref,Pid,CaptureStdout,RejectIoReqs,
+	    run_test_case_msgloop(Ref,Pid,
 				  Terminate,Comment,CurrConf,Status);
 	{timetrap_cancel_all,TCPid,_From} ->
 	    timetrap_cancel_all(TCPid, false),
-	    run_test_case_msgloop(Ref,Pid,CaptureStdout,RejectIoReqs,
+	    run_test_case_msgloop(Ref,Pid,
 				  Terminate,Comment,CurrConf,Status);
-	{get_timetrap_info,TCPid,From} ->
+	{get_timetrap_info,From,TCPid} ->
 	    Info = get_timetrap_info(TCPid, false),
 	    From ! {self(),get_timetrap_info,Info},
-	    run_test_case_msgloop(Ref,Pid,CaptureStdout,RejectIoReqs,
+	    run_test_case_msgloop(Ref,Pid,
 				  Terminate,Comment,CurrConf,Status);
 	_Other when not is_tuple(_Other) ->
 	    %% ignore anything not generated by test server
-	    run_test_case_msgloop(Ref,Pid,CaptureStdout,RejectIoReqs,
+	    run_test_case_msgloop(Ref,Pid,
 				  Terminate,Comment,CurrConf,Status);
 	_Other when element(1, _Other) /= 'EXIT',
 		    element(1, _Other) /= started,
 		    element(1, _Other) /= finished,
 		    element(1, _Other) /= print ->
 	    %% ignore anything not generated by test server
-	    run_test_case_msgloop(Ref,Pid,CaptureStdout,RejectIoReqs,
+	    run_test_case_msgloop(Ref,Pid,
 				  Terminate,Comment,CurrConf,Status)
     after Timeout ->
 	    ReturnValue
     end.
 
-run_test_case_msgloop_io(From,ReplyAs,CaptureStdout,RejectIoReqs,
-			 Msg,From,Func) ->
-    case Msg of
-	{'EXIT',_} ->
-	    From ! {io_reply,ReplyAs,{error,Func}};
-	_ ->
-	    From ! {io_reply,ReplyAs,ok}
-    end,
-    Proceed = if RejectIoReqs -> get({permit_io,From});
-		 true        -> true
-	      end,
-    if Proceed ->
-	    if CaptureStdout /= false ->
-		    CaptureStdout ! {captured,Msg};
-	       true ->
-		    ok
-	    end,
-	    output({minor,Msg},From);
-       true ->
-	    ok
-    end.
-
-output(Msg,Sender) ->
-    local_or_remote_apply({test_server_ctrl,output,[Msg,Sender]}).
-
 call_end_conf(Mod,Func,TCPid,TCExitReason,Loc,Conf,TVal) ->
-    %% Starter is also the group leader process
     Starter = self(),
     Data = {Mod,Func,TCPid,TCExitReason,Loc},
     EndConfProc =
 	fun() ->
-		group_leader(Starter, self()),
 		Supervisor = self(),
 		EndConfApply =
 		    fun() ->
@@ -1161,9 +1043,6 @@ spawn_fw_call(Mod,{init_per_testcase,Func},_,Pid,{timetrap_timeout,TVal}=Why,
 	      Loc,SendTo) ->
     FwCall =
 	fun() ->
-		%% set group leader so that printouts/comments
-		%% from the framework get printed in the logs
-		group_leader(SendTo, self()),
 		Skip = {skip,{failed,{Mod,init_per_testcase,Why}}},
 		%% if init_per_testcase fails, the test case
 		%% should be skipped
@@ -1192,9 +1071,6 @@ spawn_fw_call(Mod,{end_per_testcase,Func},EndConf,Pid,
 	       end,
     FwCall =
 	fun() ->
-		%% set group leader so that printouts/comments
-		%% from the framework get printed in the logs
-		group_leader(SendTo, self()),
 		{RetVal,Report} =
 		    case proplists:get_value(tc_status, EndConf1) of
 			undefined ->
@@ -1230,9 +1106,6 @@ spawn_fw_call(Mod,{end_per_testcase,Func},EndConf,Pid,
 spawn_fw_call(FwMod,FwFunc,_,_Pid,{framework_error,FwError},_,SendTo) ->
     FwCall =
 	fun() ->
-		%% set group leader so that printouts/comments
-		%% from the framework get printed in the logs
-		group_leader(SendTo, self()),
 		test_server_sup:framework_call(report, [framework_error,
 							{{FwMod,FwFunc},
 							 FwError}]),
@@ -1256,9 +1129,6 @@ spawn_fw_call(Mod,Func,CurrConf,Pid,Error,Loc,SendTo) ->
 	end,	    
     FwCall =
 	fun() ->
-		%% set group leader so that printouts/comments
-		%% from the framework get printed in the logs
-		group_leader(SendTo, self()),
 		case catch fw_error_notify(Mod1,Func1,[],
 					   Error,Loc) of
 		    {'EXIT',FwErrorNotifyErr} ->
@@ -1366,8 +1236,7 @@ run_test_case_eval(Mod, Func, Args0, Name, Ref, RunInit,
 
 run_test_case_eval1(Mod, Func, Args, Name, RunInit, TCCallback) ->
     %% save current state in controller loop
-    sync_send(group_leader(),set_curr_conf,{{Mod,Func},hd(Args)},
-	      5000, fun() -> exit(no_answer_from_group_leader) end),
+    tc_supervisor_req(set_curr_conf, {{Mod,Func},hd(Args)}),
     case RunInit of
 	run_init ->
 	    put(test_server_init_or_end_conf,{init_per_testcase,Func}),
@@ -1397,8 +1266,7 @@ run_test_case_eval1(Mod, Func, Args, Name, RunInit, TCCallback) ->
 		    %% call user callback function if defined
 		    NewConf1 = user_callback(TCCallback, Mod, Func, init, NewConf),
 		    %% save current state in controller loop
-		    sync_send(group_leader(),set_curr_conf,{{Mod,Func},NewConf1},
-			      5000, fun() -> exit(no_answer_from_group_leader) end),
+		    tc_supervisor_req(set_curr_conf, {{Mod,Func},NewConf1}),
 		    put(test_server_loc, {Mod,Func}),
 		    %% execute the test case
 		    {{T,Return},Loc} = {ts_tc(Mod, Func, [NewConf1]),get_loc()},
@@ -1426,8 +1294,7 @@ run_test_case_eval1(Mod, Func, Args, Name, RunInit, TCCallback) ->
 		    %% call user callback function if defined
 		    EndConf1 = user_callback(TCCallback, Mod, Func, 'end', EndConf),
 		    %% update current state in controller loop
-		    sync_send(group_leader(),set_curr_conf,EndConf1, 5000,
-			      fun() -> exit(no_answer_from_group_leader) end),
+		    tc_supervisor_req(set_curr_conf, EndConf1),
 		    {FWReturn1,TSReturn1,EndConf2} =
 			case end_per_testcase(Mod, Func, EndConf1) of
 			    SaveCfg1={save_config,_} ->
@@ -1447,8 +1314,7 @@ run_test_case_eval1(Mod, Func, Args, Name, RunInit, TCCallback) ->
 				{FWReturn,TSReturn,EndConf1}
 			end,
 		    %% clear current state in controller loop
-		    sync_send(group_leader(),set_curr_conf,undefined,
-			      5000, fun() -> exit(no_answer_from_group_leader) end),
+		    tc_supervisor_req(set_curr_conf, undefined),
 		    put(test_server_init_or_end_conf,undefined),
 		    case do_end_tc_call(Mod,Func, Loc,
 					{FWReturn1,[EndConf2]}, TSReturn1) of
@@ -1908,16 +1774,6 @@ rewrite_loc_item({M,F,_,Loc}) ->
 %% Note: Some of these functions have been moved to test_server_sup %%
 %%       in an attempt to keep this modules small (yeah, right!)    %%
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
-unicode_to_latin1(Chars) when is_list(Chars); is_binary(Chars) ->
-    lists:flatten(
-      [ case X of
-	    High when High > 255 ->
-		io_lib:format("\\{~.8B}",[X]);
-	    Low ->
-		Low
-	end || X <- unicode:characters_to_list(Chars,unicode) ]);
-unicode_to_latin1(Garbage) ->
-    Garbage.
 
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 %% format(Format) -> IoLibReturn
@@ -2510,11 +2366,7 @@ get_timetrap_info(TCPid, SendToServer) ->
 		[I|_] ->
 		    I;
 		[] when SendToServer == true ->
-		    MsgLooper = group_leader(),
-		    MsgLooper ! {get_timetrap_info,TCPid,self()},
-		    receive
-			{MsgLooper,get_timetrap_info,I} -> I
-		    end;
+		    tc_supervisor_req({get_timetrap_info,TCPid});
 		[] ->
 		    undefined
 	    end
@@ -2533,17 +2385,29 @@ hours(N)   -> trunc(N * 1000 * 60 * 60).
 minutes(N) -> trunc(N * 1000 * 60).
 seconds(N) -> trunc(N * 1000).
 
-
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
-%% sync_send(Pid,Tag,Msg,Timeout,DoAfter) -> Result
+%% tc_supervisor_req(Tag) -> Result
+%% tc_supervisor_req(Tag, Msg) -> Result
 %%
-sync_send(Pid,Tag,Msg,Timeout,DoAfter) ->
+
+tc_supervisor_req(Tag) ->
+    Pid = test_server_gl:get_tc_supervisor(group_leader()),
+    Pid ! {Tag,self()},
+    receive
+	{Pid,Tag,Result} ->
+	    Result
+    after 5000 ->
+	    error(no_answer_from_tc_supervisor)
+    end.
+
+tc_supervisor_req(Tag, Msg) ->
+    Pid = test_server_gl:get_tc_supervisor(group_leader()),
     Pid ! {Tag,self(),Msg},
     receive
 	{Pid,Tag,Result} ->
 	    Result
-    after Timeout ->
-	    DoAfter()
+    after 5000 ->
+	    error(no_answer_from_tc_supervisor)
     end.
 
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
@@ -2938,13 +2802,7 @@ comment(String) ->
 %% Read the current comment string stored in
 %% state during test case execution.
 read_comment() ->
-    MsgLooper = group_leader(),
-    MsgLooper ! {read_comment,self()},
-    receive
-	{MsgLooper,read_comment,Comment} -> Comment
-    after
-	5000 -> ""
-    end.
+    tc_supervisor_req(read_comment).
 
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 %% make_priv_dir() -> ok
@@ -2952,13 +2810,7 @@ read_comment() ->
 %% Order test server to create the private directory
 %% for the current test case.
 make_priv_dir() ->
-    MsgLooper = group_leader(),
-    group_leader() ! {make_priv_dir,self()},
-    receive
-	{MsgLooper,make_priv_dir,Result} -> Result
-    after
-	5000 -> error
-    end.
+    tc_supervisor_req(make_priv_dir).
 
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 %% os_type() -> OsType
diff --git a/lib/test_server/src/test_server_ctrl.erl b/lib/test_server/src/test_server_ctrl.erl
index 4e3cbf9087..7f04e2eb23 100644
--- a/lib/test_server/src/test_server_ctrl.erl
+++ b/lib/test_server/src/test_server_ctrl.erl
@@ -172,7 +172,7 @@
 -export([kill_slavenodes/0]).
 
 %%% TEST_SERVER INTERFACE %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
--export([output/2, print/2, print/3, print/4, print_timestamp/2]).
+-export([print/2, print/3, print/4, print_timestamp/2]).
 -export([start_node/3, stop_node/1, wait_for_node/1, is_release_available/1]).
 -export([format/1, format/2, format/3, to_string/1]).
 -export([get_target_info/0]).
@@ -203,6 +203,7 @@
 -define(coverlog_name, "cover.html").
 -define(cross_coverlog_name, "cross_cover.html").
 -define(cover_total, "total_cover.log").
+-define(unexpected_io_log, "unexpected_io.log").
 -define(last_file, "last_name").
 -define(last_link, "last_link").
 -define(last_test, "last_test").
@@ -1370,24 +1371,22 @@ kill_all_jobs([]) ->
 
 spawn_tester(Mod, Func, Args, Dir, Name, Levels, RejectIoReqs,
 	     CreatePrivDir, TCCallback, ExtraTools) ->
-    spawn_link(
-      fun() -> init_tester(Mod, Func, Args, Dir, Name, Levels, RejectIoReqs,
+    spawn_link(fun() ->
+	      init_tester(Mod, Func, Args, Dir, Name, Levels, RejectIoReqs,
 			   CreatePrivDir, TCCallback, ExtraTools)
       end).
 
-init_tester(Mod, Func, Args, Dir, Name, {SumLev,MajLev,MinLev}, RejectIoReqs,
-	    CreatePrivDir, TCCallback, ExtraTools) ->
+init_tester(Mod, Func, Args, Dir, Name, {_,_,MinLev}=Levels,
+	    RejectIoReqs, CreatePrivDir, TCCallback, ExtraTools) ->
     process_flag(trap_exit, true),
+    test_server_io:start_link(),
     put(test_server_name, Name),
     put(test_server_dir, Dir),
     put(test_server_total_time, 0),
     put(test_server_ok, 0),
     put(test_server_failed, 0),
     put(test_server_skipped, {0,0}),
-    put(test_server_summary_level, SumLev),
-    put(test_server_major_level, MajLev),
     put(test_server_minor_level, MinLev),
-    put(test_server_reject_io_reqs, RejectIoReqs),
     put(test_server_create_priv_dir, CreatePrivDir),
     put(test_server_random_seed, proplists:get_value(random_seed, ExtraTools)),
     put(test_server_testcase_callback, TCCallback),
@@ -1403,24 +1402,29 @@ init_tester(Mod, Func, Args, Dir, Name, {SumLev,MajLev,MinLev}, RejectIoReqs,
 		    put(test_server_framework_name, list_to_atom(FWName))
 	    end
     end,
+
     %% before first print, read and set logging options
     LogOpts = test_server_sup:framework_call(get_logopts, [], []),
     put(test_server_logopts, LogOpts),
-    put(test_server_log_nl, not lists:member(no_nl, LogOpts)),
+
     StartedExtraTools = start_extra_tools(ExtraTools),
+
+    test_server_io:set_job_name(Name),
+    test_server_io:set_gl_props([{levels,Levels},
+				 {auto_nl,not lists:member(no_nl, LogOpts)},
+				 {reject_io_reqs,RejectIoReqs}]),
+    group_leader(test_server_io:get_gl(true), self()),
     {TimeMy,Result} = ts_tc(Mod, Func, Args),
-    put(test_server_common_io_handler, undefined),
+    set_io_buffering(undefined),
     catch stop_extra_tools(StartedExtraTools),
     case Result of
 	{'EXIT',test_suites_done} ->
-	    print(25, "DONE, normal exit", []);
+	    ok;
 	{'EXIT',_Pid,Reason} ->
 	    print(1, "EXIT, reason ~p", [Reason]);
 	{'EXIT',Reason} ->
 	    report_severe_error(Reason),
-	    print(1, "EXIT, reason ~p", [Reason]);
-	_Other ->
-	    print(25, "DONE", [])
+	    print(1, "EXIT, reason ~p", [Reason])
     end,
     Time = TimeMy/1000000,
     SuccessStr =
@@ -1439,7 +1443,8 @@ init_tester(Mod, Func, Args, Dir, Name, {SumLev,MajLev,MinLev}, RejectIoReqs,
 	  "<tr><td></td><td><b>TOTAL</b></td><td></td><td></td><td></td>"
 	  "<td>~.3fs</td><td><b>~s</b></td><td>~p Ok, ~p Failed~s of ~p</td></tr>\n"
 	  "</tfoot>\n",
-	  [Time,SuccessStr,OkN,FailedN,SkipStr,OkN+FailedN+SkippedN]).
+	  [Time,SuccessStr,OkN,FailedN,SkipStr,OkN+FailedN+SkippedN]),
+    test_server_io:stop().
 
 report_severe_error(Reason) ->
     test_server_sup:framework_call(report, [severe_error,Reason]).
@@ -1816,8 +1821,9 @@ do_test_cases(TopCases, SkipCases,
 	    print(html,
 		  "<p><ul>\n"
 		  "<li><a href=\"~s\">Full textual log</a></li>\n"
-		  "<li><a href=\"~s\">Coverage log</a></li>\n</ul></p>\n",
-		  [?suitelog_name,?coverlog_name]),
+		  "<li><a href=\"~s\">Coverage log</a></li>\n"
+		  "<li><a href=\"~s\">Unexpected I/O log</a></li>\n</ul></p>\n",
+		  [?suitelog_name,?coverlog_name,?unexpected_io_log]),
 	    print(html,
 		  "<p>~s</p>\n" ++
 		  xhtml("<table bgcolor=\"white\" border=\"3\" cellpadding=\"5\">",
@@ -1902,10 +1908,16 @@ start_log_file() ->
     put(test_server_log_dir_base,TestDir1),
     MajorName = filename:join(TestDir1, ?suitelog_name),
     HtmlName = MajorName ++ ?html_ext,
+    UnexpectedName = filename:join(TestDir1, ?unexpected_io_log),
     {ok,Major} = file:open(MajorName, [write]),
     {ok,Html}  = file:open(HtmlName,  [write]),
+    {ok,Unexpected}  = file:open(UnexpectedName,  [write]),
+    test_server_io:set_fd(major, Major),
+    test_server_io:set_fd(html, Html),
+    test_server_io:set_fd(unexpected_io, Unexpected),
     put(test_server_major_fd,Major),
     put(test_server_html_fd,Html),
+    put(test_server_unexpected_io, Unexpected),
 
     make_html_link(filename:absname(?last_test ++ ?html_ext),
 		   HtmlName, filename:basename(Dir)),
@@ -1916,7 +1928,7 @@ start_log_file() ->
     PrivDir = filename:join(TestDir1, ?priv_dir),
     ok = file:make_dir(PrivDir),
     put(test_server_priv_dir,PrivDir++"/"),
-    print_timestamp(13,"Suite started at "),
+    print_timestamp(major, "Suite started at "),
 
     LogInfo = [{topdir,Dir},{rundir,lists:flatten(TestDir1)}],
     test_server_sup:framework_call(report, [loginfo,LogInfo]),
@@ -1958,13 +1970,14 @@ make_html_link(LinkName, Target, Explanation) ->
 %% Some header info will also be inserted into the log file.
 
 start_minor_log_file(Mod, Func) ->
+    MFA = {Mod,Func,1},
     LogDir = get(test_server_log_dir_base),
     Name0 = lists:flatten(io_lib:format("~s.~s~s", [Mod,Func,?html_ext])),
     Name = downcase(Name0),
     AbsName = filename:join(LogDir, Name),
     case file:read_file_info(AbsName) of
 	{error,_} ->                         %% normal case, unique name
-	    start_minor_log_file1(Mod, Func, LogDir, AbsName);
+	    start_minor_log_file1(Mod, Func, LogDir, AbsName, MFA);
 	{ok,_} ->                            %% special case, duplicate names
 	    {_,S,Us} = now(),
 	    Name1_0 =
@@ -1973,14 +1986,15 @@ start_minor_log_file(Mod, Func) ->
 							     ?html_ext])),
 	    Name1 = downcase(Name1_0),
 	    AbsName1 = filename:join(LogDir, Name1),
-	    start_minor_log_file1(Mod, Func, LogDir, AbsName1)
+	    start_minor_log_file1(Mod, Func, LogDir, AbsName1, MFA)
     end.
 
-start_minor_log_file1(Mod, Func, LogDir, AbsName) ->
+start_minor_log_file1(Mod, Func, LogDir, AbsName, MFA) ->
     {ok,Fd} = file:open(AbsName, [write]),
     Lev = get(test_server_minor_level)+1000, %% far down in the minor levels
     put(test_server_minor_fd, Fd),
-    
+    test_server_gl:set_minor_fd(group_leader(), Fd, MFA),
+
     TestDescr = io_lib:format("Test ~p:~p result", [Mod,Func]),
     {Header,Footer} =
 	case test_server_sup:framework_call(get_html_wrapper, 
@@ -2028,6 +2042,7 @@ start_minor_log_file1(Mod, Func, LogDir, AbsName) ->
     AbsName.
 
 stop_minor_log_file() ->
+    test_server_gl:unset_minor_fd(group_leader()),
     Fd = get(test_server_minor_fd),
     Footer = get(test_server_minor_footer),
     io:fwrite(Fd, "</pre>\n" ++ Footer, []),
@@ -2448,27 +2463,38 @@ maybe_get_privdir() ->
 %% reason, the Mode argument specifies if a parallel group is currently
 %% being executed.
 %%
-%% A parallel test case process will always set the dictionary value
-%% 'test_server_common_io_handler' to the pid of the main (starting)
-%% process. With this value set, the print/3 function will send print
-%% messages to the main process instead of writing the data to file
-%% (only true for printouts to common log files).
+%% The low-level mechanism for buffering IO for the common log files
+%% is handled by the test_server_io module. Buffering is turned on by
+%% test_server_io:start_transaction/0 and off by calling
+%% test_server_io:end_transaction/0. The buffered data for the transaction
+%% can printed by calling test_server_io:print_buffered/1.
+%%
+%% This module is responsible for turning on IO buffering and to later
+%% test_server_io:print_buffered/1 to print the data. To help with this,
+%% two variables in the process dictionary are used:
+%% 'test_server_common_io_handler' and 'test_server_queued_io'. The values
+%% are set to as follwing:
+%%
+%%   Value	Meaning
+%%   -----     -------
+%%   undefined	No parallel test cases running
+%%   {tc,Pid}	Running test cases in a top-level parallel group
+%%   {Ref,Pid}	Running sequential test case inside a parallel group
+%%
+%% FIXME: The Pid is no longer used.
 %%
 %% If a conf group nested under a parallel group in the test
 %% specification should be started, the 'test_server_common_io_handler'
-%% value gets set also on the main process. This causes all printouts
-%% to common files - both from parallel test cases and from cases
-%% executed by the main process - to all end up as messages in the
-%% inbox of the main process.
+%% value gets set also on the main process.
 %%
 %% During execution of a parallel group (or of a group nested under a
 %% parallel group), *any* new test case being started gets registered
 %% in a list saved in the dictionary with 'test_server_queued_io' as key.
 %% When the top level parallel group is finished (only then can we be
 %% sure all parallel test cases have finished and "reported in"), the
-%% list of test cases is traversed in order and printout messages from
-%% each process - including the main process - are handled in turn. See
-%% handle_test_case_io_and_status/0 for details.
+%% list of test cases is traversed in order and test_server_io:print_buffered/1
+%% can be called for each test case. See handle_test_case_io_and_status/0
+%% for details.
 %%
 %% To be able to handle nested conf groups with different properties,
 %% the Mode argument specifies a list of {Ref,Properties} tuples.
@@ -2611,16 +2637,15 @@ run_test_cases_loop([{auto_skip_case,{Type,Ref,Case,Comment},SkipMode}|Cases],
 
 run_test_cases_loop([{auto_skip_case,{Case,Comment},SkipMode}|Cases],
 		    Config, TimetrapData, Mode, Status) ->
-    {Mod,Func} = skip_case(auto, undefined, get(test_server_case_num)+1, Case, Comment,
-			   (undefined /= get(test_server_common_io_handler)), SkipMode),
+    {Mod,Func} = skip_case(auto, undefined, get(test_server_case_num)+1,
+			   Case, Comment, is_io_buffered(), SkipMode),
     test_server_sup:framework_call(report, [tc_auto_skip,{?pl2a(Mod),Func,Comment}]),
     run_test_cases_loop(Cases, Config, TimetrapData, Mode,
 			update_status(skipped, Mod, Func, Status));
 
 run_test_cases_loop([{skip_case,{conf,Ref,Case,Comment}}|Cases0],
 		    Config, TimetrapData, Mode, Status) ->
-    {Mod,Func} = skip_case(user, Ref, 0, Case, Comment,
-			   (undefined /= get(test_server_common_io_handler))),
+    {Mod,Func} = skip_case(user, Ref, 0, Case, Comment, is_io_buffered()),
     {Cases,Config1} =
 	case curr_ref(Mode) of
 	    Ref ->
@@ -2636,8 +2661,8 @@ run_test_cases_loop([{skip_case,{conf,Ref,Case,Comment}}|Cases0],
 
 run_test_cases_loop([{skip_case,{Case,Comment}}|Cases],
 		    Config, TimetrapData, Mode, Status) ->
-    {Mod,Func} = skip_case(user, undefined, get(test_server_case_num)+1, Case, Comment,
-			   (undefined /= get(test_server_common_io_handler))),
+    {Mod,Func} = skip_case(user, undefined, get(test_server_case_num)+1,
+			   Case, Comment, is_io_buffered()),
     test_server_sup:framework_call(report, [tc_user_skip,{?pl2a(Mod),Func,Comment}]),
     run_test_cases_loop(Cases, Config, TimetrapData, Mode,
 			update_status(skipped, Mod, Func, Status));
@@ -3036,21 +3061,19 @@ run_test_cases_loop([{Mod,Case}|Cases], Config, TimetrapData, Mode, Status) ->
 
 run_test_cases_loop([{Mod,Func,Args}|Cases], Config, TimetrapData, Mode, Status) ->
     Num = put(test_server_case_num, get(test_server_case_num)+1),
+
     %% check the current execution mode and save info about the case if
     %% detected that printouts to common log files is handled later
-    case check_prop(parallel, Mode) of
+
+    case check_prop(parallel, Mode) =:= false andalso is_io_buffered() of
+	true ->
+	    %% sequential test case nested in a parallel group;
+	    %% io is buffered, so we must queue this test case
+	    queue_test_case_io(undefined, self(), Num+1, Mod, Func);
 	false ->
-	    case get(test_server_common_io_handler) of
-		undefined ->
-		    %% io printouts are written to straight to file
-		    ok;
-		_ ->
-		    %% io messages are buffered, put test case in queue
-		    queue_test_case_io(undefined, self(), Num+1, Mod, Func)
-	    end;
-	_ ->
 	    ok
     end,
+
     case run_test_case(undefined, Num+1, Mod, Func, Args,
 		       run_init, target, TimetrapData, Mode) of
 	%% callback to framework module failed, exit immediately
@@ -3099,8 +3122,8 @@ run_test_cases_loop([{Mod,Func,Args}|Cases], Config, TimetrapData, Mode, Status)
 	%% the test case is being executed in parallel with the main process (and
 	%% other test cases) and Pid is the dedicated process executing the case
 	Pid ->
-	    %% io from Pid will be buffered in the main process inbox and handled
-	    %% later, so we have to save info about the case
+	    %% io from Pid will be buffered by the test_server_io process and
+	    %% handled later, so we have to save info about the case
 	    queue_test_case_io(undefined, Pid, Num+1, Mod, Func),
 	    run_test_cases_loop(Cases, Config, TimetrapData, Mode, Status)
     end;
@@ -3361,7 +3384,9 @@ skip_case(Type, Ref, CaseNum, Case, Comment, SendSync, Mode) ->
     if SendSync ->
 	    queue_test_case_io(Ref, self(), CaseNum, Mod, Func),
 	    self() ! {started,Ref,self(),CaseNum,Mod,Func},
+	    test_server_io:start_transaction(),
 	    skip_case1(Type, CaseNum, Mod, Func, Comment, Mode),
+	    test_server_io:end_transaction(),
 	    self() ! {finished,Ref,self(),CaseNum,Mod,Func,skipped,{0,skipped,[]}};
        not SendSync ->
 	    skip_case1(Type, CaseNum, Mod, Func, Comment, Mode)
@@ -3502,13 +3527,20 @@ modify_cases_upto1(Ref, CopyOp, [C|T], Orig, Alt) ->
 %%
 %% Save info about current process (always the main process) buffering
 %% io printout messages from parallel test case processes (*and* possibly
-%% also the main process). If the value is the default 'undefined',
-%% io is not buffered but printed directly to file (see print/3).
+%% also the main process).
 
 set_io_buffering(IOHandler) ->
     put(test_server_common_io_handler, IOHandler).
 
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%% is_io_buffered() -> true|false
+%%
+%% Test whether is being buffered.
+
+is_io_buffered() ->
+    get(test_server_common_io_handler) =/= undefined.
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 %% queue_test_case_io(Pid, Num, Mod, Func) -> ok
 %%
 %% Save info about test case that gets its io buffered. This can
@@ -3555,7 +3587,7 @@ wait_and_resend(Ref, [{_,CurrPid,CaseNum,Mod,Func}|Ps] = Cases, Ok,Skip,Fail) ->
     receive
 	{finished,_Ref,CurrPid,CaseNum,Mod,Func,Result,_RetVal} = Msg ->
 	    %% resend message to main process so that it can be used
-	    %% to handle buffered io messages later
+	    %% to test_server_io:print_buffered/1 later
 	    self() ! Msg,
 	    MF = {Mod,Func},
 	    {Ok1,Skip1,Fail1} =
@@ -3586,16 +3618,18 @@ rm_cases_upto(Ref, [_|Ps]) ->
 %%
 %% Each parallel test case process prints to its own minor log file during
 %% execution. The common log files (major, html etc) must however be
-%% written to sequentially. The test case processes send print requests
-%% to the main (starting) process (the same process executing
-%% run_test_cases_loop/4), which handles these requests in the same
-%% order that the test case processes were started.
-%%
-%% An io session is always started with a {started,Ref,Pid,Num,Mod,Func}
-%% message and terminated with {finished,Ref,Pid,Num,Mod,Func,Result,RetVal}.
-%% The result shipped with the finished message from a parallel process
-%% is used to update status data of the current test run. An 'EXIT'
-%% message from each parallel test case process (after finishing and
+%% written to sequentially. This is handled by calling
+%% test_server_io:start_transaction/0 to tell the test_server_io process
+%% to buffer all print requests.
+%%
+%% An io session is always started with a
+%% {started,Ref,Pid,Num,Mod,Func} message (and
+%% test_server_io:start_transaction/0 will be called) and terminated
+%% with {finished,Ref,Pid,Num,Mod,Func,Result,RetVal} (and
+%% test_server_io:end_transaction/0 will be called).  The result
+%% shipped with the finished message from a parallel process is used
+%% to update status data of the current test run. An 'EXIT' message
+%% from each parallel test case process (after finishing and
 %% terminating) is also received and handled here.
 %%
 %% During execution of a parallel group, any cases (conf or normal)
@@ -3604,13 +3638,13 @@ rm_cases_upto(Ref, [_|Ps]) ->
 %% correct sequence. This function handles also the print messages
 %% generated by nested group cases that have been executed sequentially
 %% by the main process (note that these cases do not generate 'EXIT'
-%% messages, only 'start', 'print' and 'finished' messages).
+%% messages, only 'start' and 'finished' messages).
 %%
 %% See the header comment for run_test_cases_loop/4 for more
 %% info about IO handling.
 %%
 %% Note: It is important that the type of messages handled here
-%% do not get consumated by test_server:run_test_case_msgloop/5
+%% do not get consumed by test_server:run_test_case_msgloop/5
 %% during the test case execution (e.g. in the catch clause of
 %% the receive)!
 
@@ -3637,7 +3671,7 @@ handle_test_case_io_and_status() ->
 
 %% Handle cases (without Ref) that belong to the top parallel group (i.e. when Refs = [])
 handle_io_and_exit_loop([], [{undefined,CurrPid,CaseNum,Mod,Func}|Ps] = Cases, Ok,Skip,Fail) ->
-    %% retreive the start message for the current io session (= testcase)
+    %% retrieve the start message for the current io session (= testcase)
     receive
 	{started,_,CurrPid,CaseNum,Mod,Func} ->
 	    {Ok1,Skip1,Fail1} =
@@ -3679,9 +3713,11 @@ handle_io_and_exits(Main, CurrPid, CaseNum, Mod, Func, Cases) ->
     receive
 	%% end of io session from test case executed by main process
 	{finished,_,Main,CaseNum,Mod,Func,Result,_RetVal} ->
+	    test_server_io:print_buffered(CurrPid),
 	    {Result,{Mod,Func}};
 	%% end of io session from test case executed by parallel process
 	{finished,_,CurrPid,CaseNum,Mod,Func,Result,RetVal} ->
+	    test_server_io:print_buffered(CurrPid),
 	    case Result of
 		ok ->
 		    put(test_server_ok, get(test_server_ok)+1);
@@ -3694,13 +3730,9 @@ handle_io_and_exits(Main, CurrPid, CaseNum, Mod, Func, Cases) ->
 	    end,
 	    {Result,{Mod,Func}};
 
-	%% print to common log file
-	{print,CurrPid,Detail,Msg} ->
-	    output({Detail,Msg}, internal),
-	    handle_io_and_exits(Main, CurrPid, CaseNum, Mod, Func, Cases);
-
 	%% unexpected termination of test case process
 	{'EXIT',TCPid,Reason} when Reason /= normal ->
+	    test_server_io:print_buffered(CurrPid),
 	    {value,{_,_,Num,M,F}} = lists:keysearch(TCPid, 2, Cases),
 	    print(1, "Error! Process for test case #~p (~p:~p) died! Reason: ~p",
 		  [Num, M, F, Reason]),
@@ -3735,48 +3767,46 @@ handle_io_and_exits(Main, CurrPid, CaseNum, Mod, Func, Cases) ->
 run_test_case(Ref, Num, Mod, Func, Args, RunInit, Where, TimetrapData) ->
     file:set_cwd(filename:dirname(get(test_server_dir))),
     run_test_case1(Ref, Num, Mod, Func, Args, RunInit, Where,
-		   TimetrapData, [], [], self()).
+		   TimetrapData, [], self()).
 
 run_test_case(Ref, Num, Mod, Func, Args, skip_init, Where, TimetrapData, Mode) ->
     %% a conf case is always executed by the main process
     run_test_case1(Ref, Num, Mod, Func, Args, skip_init, Where,
-		   TimetrapData, [], Mode, self());
+		   TimetrapData, Mode, self());
 
 run_test_case(Ref, Num, Mod, Func, Args, RunInit, Where, TimetrapData, Mode) ->
     file:set_cwd(filename:dirname(get(test_server_dir))),
+    Main = self(),
     case check_prop(parallel, Mode) of
 	false ->
 	    %% this is a sequential test case
 	    run_test_case1(Ref, Num, Mod, Func, Args, RunInit, Where,
-			   TimetrapData, [], Mode, self());
+			   TimetrapData, Mode, Main);
 	_Ref ->
 	    %% this a parallel test case, spawn the new process
-	    Main = self(),
-	    {dictionary,State} = process_info(self(), dictionary),
-	    spawn_link(fun() ->
-			   run_test_case1(Ref, Num, Mod, Func, Args, RunInit, Where,
-					  TimetrapData, State, Mode, Main)
-		       end)
+	    Dictionary = get(),
+	    {dictionary,Dictionary} = process_info(self(), dictionary),
+	    spawn_link(
+	      fun() ->
+		      process_flag(trap_exit, true),
+		      [put(Key, Val) || {Key,Val} <- Dictionary],
+		      set_io_buffering({tc,Main}),
+		      run_test_case1(Ref, Num, Mod, Func, Args, RunInit,
+				     Where, TimetrapData, Mode, Main)
+	      end)
     end.
 
 run_test_case1(Ref, Num, Mod, Func, Args, RunInit, Where,
-	       TimetrapData, State, Mode, Main) ->
-    %% if this runs on a parallel test case process,
-    %% copy the dictionary from the main process
-    do_if_parallel(Main, fun() -> process_flag(trap_exit, true) end, ok),
-    CopyDict = fun() -> lists:foreach(fun({Key,Val}) ->
-					      put(Key, Val)
-				      end, State)
-	       end,
-    do_if_parallel(Main, CopyDict, ok),
-    do_if_parallel(Main, fun() -> 
-				 put(test_server_common_io_handler, {tc,Main})
-			 end, ok),
+	       TimetrapData, Mode, Main) ->
+    group_leader(test_server_io:get_gl(Main == self()), self()),
+
     %% if io is being buffered, send start io session message
     %% (no matter if case runs on parallel or main process)
-    case get(test_server_common_io_handler) of
-	undefined -> ok;
-	_ -> Main ! {started,Ref,self(),Num,Mod,Func}
+    case is_io_buffered() of
+	false -> ok;
+	true ->
+	    test_server_io:start_transaction(),
+	    Main ! {started,Ref,self(),Num,Mod,Func}
     end,
     TSDir = get(test_server_dir),
     case Where of
@@ -3785,6 +3815,7 @@ run_test_case1(Ref, Num, Mod, Func, Args, RunInit, Where,
 	host ->
 	    ok
     end,
+
     print(major, "=case          ~p:~p", [Mod, Func]),
     MinorName = start_minor_log_file(Mod, Func),
     print(minor, "<a name=\"top\"></a>", [], internal_raw),
@@ -3836,13 +3867,12 @@ run_test_case1(Ref, Num, Mod, Func, Args, RunInit, Where,
 	  [num2str(Num),fw_name(Mod),GroupName,MinorBase,Func,
 	   MinorBase,MinorBase]),
 
-    do_if_parallel(Main, ok, fun erlang:yield/0),
+    do_unless_parallel(Main, fun erlang:yield/0),
 
-    RejectIoReqs = get(test_server_reject_io_reqs),
     %% run the test case
     {Result,DetectedFail,ProcsBefore,ProcsAfter} =
 	run_test_case_apply(Num, Mod, Func, [UpdatedArgs], get_name(Mode),
-			    RunInit, Where, TimetrapData, RejectIoReqs),
+			    RunInit, Where, TimetrapData),
     {Time,RetVal,Loc,Opts,Comment} =
 	case Result of
 	    Normal={_Time,_RetVal,_Loc,_Opts,_Comment} -> Normal;
@@ -3854,7 +3884,7 @@ run_test_case1(Ref, Num, Mod, Func, Args, RunInit, Where,
     print_timestamp(minor, "Ended at "),
     print(major, "=ended         ~s", [lists:flatten(timestamp_get(""))]),
 
-    do_if_parallel(Main, ok, fun() -> file:set_cwd(filename:dirname(TSDir)) end),
+    do_unless_parallel(Main, fun() -> file:set_cwd(filename:dirname(TSDir)) end),
 
     %% call the appropriate progress function clause to print the results to log
     Status =
@@ -3963,10 +3993,13 @@ run_test_case1(Ref, Num, Mod, Func, Args, RunInit, Where,
 
     %% if io is being buffered, send finished message
     %% (no matter if case runs on parallel or main process)
-    case get(test_server_common_io_handler) of
-	undefined -> ok;
-	_ -> Main ! {finished,Ref,self(),Num,Mod,Func,
-		     ?mod_result(Status),{Time,RetVal,Opts}}
+    case is_io_buffered() of
+	false ->
+	    ok;
+	true ->
+	    test_server_io:end_transaction(),
+	    Main ! {finished,Ref,self(),Num,Mod,Func,
+		    ?mod_result(Status),{Time,RetVal,Opts}}
     end,
     {Time,RetVal,Opts}.
 
@@ -3974,18 +4007,11 @@ run_test_case1(Ref, Num, Mod, Func, Args, RunInit, Where,
 %%--------------------------------------------------------------------
 %% various help functions
 
-%% Call If() if we're on parallel process, or
-%% call Else() if we're on main process
-do_if_parallel(Pid, If, Else) ->
+%% Call Action if we are running on the main process (not parallel).
+do_unless_parallel(Main, Action) when is_function(Action, 0) ->
     case self() of
-	Pid ->
-	    if is_function(Else) -> Else();
-	       true -> Else
-	    end;
-	_ ->
-	    if is_function(If) -> If();
-	       true -> If
-	    end
+	Main -> Action();
+	_ -> ok
     end.
 
 num2str(0) -> "";
@@ -4461,7 +4487,7 @@ do_format_exception(Reason={Error,Stack}) ->
 
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 %% run_test_case_apply(CaseNum, Mod, Func, Args, Name, RunInit,
-%%                     Where, TimetrapData, RejectIoReqs) ->
+%%                     Where, TimetrapData) ->
 %%  {{Time,RetVal,Loc,Opts,Comment},DetectedFail,ProcessesBefore,ProcessesAfter} |
 %%  {{died,Reason,unknown,Comment},DetectedFail,ProcessesBefore,ProcessesAfter}
 %% Name = atom()
@@ -4481,20 +4507,20 @@ do_format_exception(Reason={Error,Stack}) ->
 %% result back over the socket. Else test_server runs the case directly on host.
 
 run_test_case_apply(CaseNum, Mod, Func, Args, Name, RunInit, host,
-		    TimetrapData, RejectIoReqs) ->
+		    TimetrapData) ->
     test_server:run_test_case_apply({CaseNum,Mod,Func,Args,Name,RunInit,
-				     TimetrapData,RejectIoReqs});
+				     TimetrapData});
 run_test_case_apply(CaseNum, Mod, Func, Args, Name, RunInit, target,
-		    TimetrapData, RejectIoReqs) ->
+		    TimetrapData) ->
     case get(test_server_ctrl_job_sock) of
 	undefined ->
 	    %% local target
 	    test_server:run_test_case_apply({CaseNum,Mod,Func,Args,Name,RunInit,
-					     TimetrapData,RejectIoReqs});
+					     TimetrapData});
 	JobSock ->
 	    %% remote target
 	    request(JobSock, {test_case,{CaseNum,Mod,Func,Args,Name,RunInit,
-					 TimetrapData,RejectIoReqs}}),
+					 TimetrapData}}),
 	    read_job_sock_loop(JobSock)
     end.
 
@@ -4506,16 +4532,6 @@ run_test_case_apply(CaseNum, Mod, Func, Args, Name, RunInit, target,
 %%
 %% Just like io:format, except that depending on the Detail value, the output
 %% is directed to console, major and/or minor log files.
-%%
-%% To handle printouts to common (not minor) log files from parallel test
-%% case processes, the test_server_common_io_handler value is checked. If
-%% set, the data is sent to the main controlling process. Note that test
-%% cases that belong to a conf group nested under a parallel group will also
-%% get its io data sent to main rather than immediately printed out, even
-%% if the test cases are executed by the same, main, process (ie the main
-%% process sends messages to itself then).
-%%
-%% Buffered io is handled by the handle_test_case_io_and_status/0 function.
 
 print(Detail, Format) ->
     print(Detail, Format, []).
@@ -4528,19 +4544,7 @@ print(Detail, Format, Args, Printer) ->
     print_or_buffer(Detail, Msg, Printer).
 
 print_or_buffer(Detail, Msg, Printer) ->
-    case get(test_server_minor_level) of
-	_ when Detail == minor ->
-	    output({Detail,Msg}, Printer);
-	MinLevel when is_number(Detail), Detail >= MinLevel ->
-	    output({Detail,Msg}, Printer);
-	_ ->					% Detail < Minor | major | html
-	    case get(test_server_common_io_handler) of
-		undefined ->
-		    output({Detail,Msg}, Printer);
-		{_,MainPid} ->
-		    MainPid ! {print,self(),Detail,Msg}
-	    end
-    end.
+    test_server_gl:print(group_leader(), Detail, Msg, Printer).
 
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 %% print_timestamp(Detail, Leader) -> ok
@@ -4604,107 +4608,6 @@ format(Detail, Format, Args) ->
     print_or_buffer(Detail, Str, self()).
 
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
-%% output({Level,Message}, Sender) -> ok
-%% Level = integer() | minor | major | html
-%% Message = string() | [integer()]
-%% Sender = string() | internal
-%%
-%% Outputs the message on the channels indicated by Level. If Level is an
-%% atom, only the corresponding channel receives the output. When Level is
-%% an integer console, major and/or minor log file will receive output
-%% depending on the user set thresholds (see get_levels/0, set_levels/3)
-%%
-%% When printing on the console, the message is prefixed with the test
-%% suite's name. In case a name is not set (yet), Sender is used.
-%%
-%% When not outputting to the console, and the Sender is 'internal',
-%% the message is prefixed with "=== ", so that it will be apparent that
-%% the message comes from the test server and not the test suite itself.
-
-output({Level,Msg}, Sender) when is_integer(Level) ->
-    SumLev = get(test_server_summary_level),
-    if  Level =< SumLev ->
-	    output_to_fd(stdout, Msg, Sender);
-	true ->
-	    ok
-    end,
-    MajLev = get(test_server_major_level),
-    if  Level =< MajLev ->
-	    output_to_fd(get(test_server_major_fd), Msg, Sender);
-	true ->
-	    ok
-    end,
-    MinLev = get(test_server_minor_level),
-    if  Level >= MinLev ->
-	    output_to_fd(get(test_server_minor_fd), Msg, Sender);
-	true ->
-	    ok
-    end;
-output({minor,Bytes}, Sender) when is_list(Bytes) ->
-    output_to_fd(get(test_server_minor_fd), Bytes, Sender);
-output({major,Bytes}, Sender) when is_list(Bytes) ->
-    output_to_fd(get(test_server_major_fd), Bytes, Sender);
-output({minor,Bytes}, Sender) when is_binary(Bytes) ->
-    output_to_fd(get(test_server_minor_fd),binary_to_list(Bytes), Sender);
-output({major,Bytes}, Sender) when is_binary(Bytes) ->
-    output_to_fd(get(test_server_major_fd),binary_to_list(Bytes), Sender);
-output({html,Msg}, _Sender) ->
-    case get(test_server_html_fd) of
-	undefined ->
-	    ok;
-	Fd ->
-	    io:put_chars(Fd,Msg),
-	    case file:position(Fd, {cur, 0}) of
-		{ok, Pos} ->
-		    %% We are writing to a seekable file.  Finalise so
-		    %% we get complete valid (and viewable) HTML code.
-		    %% Then rewind to overwrite the finalising code.
-		    io:put_chars(Fd, "\n</table>\n"),
-		    case get(test_server_html_footer) of
-			undefined ->
-			    io:put_chars(Fd, "</body>\n</html>\n");
-			Footer ->
-			    io:put_chars(Fd, Footer)
-		    end,
-		    file:position(Fd, Pos);
-		{error, epipe} ->
-		    %% The file is not seekable.  We cannot erase what
-		    %% we've already written --- so the reader will
-		    %% have to wait until we're done.
-		    ok
-	    end
-    end;
-output({minor,Data}, Sender) ->
-    output_to_fd(get(test_server_minor_fd),
-		 lists:flatten(io_lib:format(
-				 "Unexpected output: ~p~n", [Data])),Sender);
-output({major,Data}, Sender) ->
-    output_to_fd(get(test_server_major_fd),
-		 lists:flatten(io_lib:format(
-				 "Unexpected output: ~p~n", [Data])),Sender).
-
-output_to_fd(stdout, Msg, Sender) ->
-    Name =
-	case get(test_server_name) of
-	    undefined -> Sender;
-	    Other -> Other
-	end,
-    io:format("Testing ~s: ~s\n", [Name, lists:flatten(Msg)]);
-output_to_fd(undefined, _Msg, _Sender) ->
-    ok;
-output_to_fd(Fd, Msg=[$=|_], internal) ->
-    io:put_chars(Fd, [Msg,"\n"]);
-
-output_to_fd(Fd, Msg, internal) ->
-    io:put_chars(Fd, [$=,$=,$=,$ , Msg, "\n"]);
-
-output_to_fd(Fd, Msg, _Sender) ->
-    case get(test_server_log_nl) of
-	false -> io:put_chars(Fd, Msg);
-	_     -> io:put_chars(Fd, [Msg,"\n"])
-    end.
-
-%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 %% xhtml(BasicHtml, XHtml) -> BasicHtml | XHtml
 %%
 xhtml(HTML, XHTML) ->
diff --git a/lib/test_server/src/test_server_gl.erl b/lib/test_server/src/test_server_gl.erl
new file mode 100644
index 0000000000..d32c7c07dc
--- /dev/null
+++ b/lib/test_server/src/test_server_gl.erl
@@ -0,0 +1,293 @@
+%%
+%% %CopyrightBegin%
+%%
+%% Copyright Ericsson AB 2012. 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
+%% compliance with the License. You should have received a copy of the
+%% Erlang Public License along with this software. If not, it can be
+%% retrieved online at http://www.erlang.org/.
+%%
+%% Software distributed under the License is distributed on an "AS IS"
+%% basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
+%% the License for the specific language governing rights and limitations
+%% under the License.
+%%
+%% %CopyrightEnd%
+%%
+%% This module implements group leader processes for test cases.
+%% Each group leader process handles output to the minor log file for
+%% a test case, and calls test_server_io to handle output to the common
+%% log files. The group leader processes are created and destroyed
+%% through the test_server_io module/process.
+
+-module(test_server_gl).
+-export([start_link/0,stop/1,set_minor_fd/3,unset_minor_fd/1,
+	 get_tc_supervisor/1,print/4,set_props/2]).
+
+-export([init/1,handle_call/3,handle_cast/2,handle_info/2,terminate/2]).
+
+-record(st, {tc_supervisor :: 'none'|pid(),    %Test case supervisor
+	     tc :: mfa(),		       %Current test case MFA
+	     minor :: 'none'|pid(),	       %Minor fd
+	     minor_monitor,		       %Monitor ref for minor fd
+	     capture :: 'none'|pid(),	       %Capture output
+	     reject_io :: boolean(),	       %Reject I/O requests...
+	     permit_io,			       %... and exceptions
+	     auto_nl=true :: boolean(),	       %Automatically add NL
+	     levels			       %{Stdout,Major,Minor}
+	    }).
+
+%% start_link()
+%%  Start a new group leader process. Only to be called by
+%%  the test_server_io process.
+
+start_link() ->
+    case gen_server:start_link(?MODULE, [], []) of
+	{ok,Pid} ->
+	    {ok,Pid};
+	Other ->
+	    Other
+    end.
+
+
+%% stop(Pid)
+%%  Stop a group leader process. Only to be called by
+%%  the test_server_io process.
+
+stop(GL) ->
+    gen_server:cast(GL, stop).
+
+
+%% set_minor_fd(GL, Fd, MFA)
+%%  GL = Pid for the group leader process
+%%  Fd = file descriptor for the minor log file
+%%  MFA = {M,F,A} for the test case owning the minor log file
+%%
+%%  Register the file descriptor for the minor log file. Subsequent
+%%  IO directed to the minor log file will be written to this file.
+%%  Also register the currently executing process at the testcase
+%%  supervisor corresponding to this group leader process.
+
+set_minor_fd(GL, Fd, MFA) ->
+    req(GL, {set_minor_fd,Fd,MFA,self()}).
+
+
+%% unset_minor_fd(GL, Fd, MFA)
+%%  GL = Pid for the group leader process
+%%
+%%  Unregister the file descriptor for minor log file (typically
+%%  because the test case has ended the minor log file is about
+%%  to be closed). Subsequent IO (for example, by a process spawned
+%%  by the testcase process) will go to the unexpected_io log file.
+
+unset_minor_fd(GL) ->
+    req(GL, unset_minor_fd).
+
+
+%% get_tc_supervisor(GL)
+%%  GL = Pid for the group leader process
+%%
+%%  Return the Pid for the process that supervises the test case
+%%  that has this group leader.
+
+get_tc_supervisor(GL) ->
+    req(GL, get_tc_supervisor).
+
+
+%% print(GL, Detail, Format, Args) -> ok
+%%  GL = Pid for the group leader process
+%%  Detail = integer() | minor | major | html | stdout
+%%  Msg = iodata()
+%%  Printer = internal | pid()
+%%
+%%  Print a message to one of the log files. If Detail is an integer,
+%%  it will be compared to the levels (set by set_props/2) to
+%%  determine which log file(s) that are to receive the output. If
+%%  Detail is an atom, the value of the atom will directly determine
+%%  which log file to use.  IO to the minor log file will be handled
+%%  directly by this group leader process (printing to the file set by
+%%  set_minor_fd/3), and all other IO will be handled by calling
+%%  test_server_io:print/3.
+
+print(GL, Detail, Msg, Printer) ->
+    req(GL, {print,Detail,Msg,Printer}).
+
+
+%% set_props(GL, [PropertyTuple])
+%%  GL = Pid for the group leader process
+%%  PropertyTuple = {levels,{Show,Major,Minor}} |
+%%                  {auto_nl,boolean()} |
+%%                  {reject_io_reqs,boolean()}
+%%
+%%  Set properties for this group leader process.
+
+set_props(GL, PropList) ->
+    req(GL, {set_props,PropList}).
+
+%%% Internal functions.
+
+init([]) ->
+    {ok,#st{tc_supervisor=none,
+	    minor=none,
+	    minor_monitor=none,
+	    capture=none,
+	    reject_io=false,
+	    permit_io=gb_sets:empty(),
+	    auto_nl=true,
+	    levels={1,19,10}
+	   }}.
+
+req(GL, Req) ->
+    gen_server:call(GL, Req, infinity).
+
+handle_call(get_tc_supervisor, _From, #st{tc_supervisor=Pid}=St) ->
+    {reply,Pid,St};
+handle_call({set_minor_fd,Fd,MFA,Supervisor}, _From, St) ->
+    Ref = erlang:monitor(process, Fd),
+    {reply,ok,St#st{tc=MFA,minor=Fd,minor_monitor=Ref,
+		    tc_supervisor=Supervisor}};
+handle_call(unset_minor_fd, _From, St) ->
+    {reply,ok,St#st{minor=none,tc_supervisor=none}};
+handle_call({set_props,PropList}, _From, St) ->
+    {reply,ok,do_set_props(PropList, St)};
+handle_call({print,Detail,Msg,Printer}, {From,_}, St) ->
+    output(Detail, Msg, Printer, From, St),
+    {reply,ok,St}.
+
+handle_cast(stop, St) ->
+    {stop,normal,St}.
+
+handle_info({'DOWN',Ref,process,_,_}, #st{minor_monitor=Ref}=St) ->
+    {noreply,St#st{minor=none,minor_monitor=none}};
+handle_info({permit_io,Pid}, #st{permit_io=P}=St) ->
+    {noreply,St#st{permit_io=gb_sets:add(Pid, P)}};
+handle_info({capture,Cap0}, St) ->
+    Cap = case Cap0 of
+	      false -> none;
+	      Pid when is_pid(Cap0) -> Pid
+	  end,
+    {noreply,St#st{capture=Cap}};
+handle_info({io_request,From,ReplyAs,Req}=IoReq, St) ->
+    try	io_req(Req, From, St) of
+	passthrough ->
+	    group_leader() ! IoReq;
+	Data ->
+	    case is_io_permitted(From, St) of
+		false ->
+		    ok;
+		true ->
+		    case St of
+			#st{capture=none} ->
+			    ok;
+			#st{capture=CapturePid} ->
+			    CapturePid ! {captured,Data}
+		    end,
+		    output(minor, Data, From, From, St)
+	    end,
+	    From ! {io_reply,ReplyAs,ok}
+    catch
+	_:_ ->
+	    {io_reply,ReplyAs,{error,arguments}}
+    end,
+    {noreply,St};
+handle_info({structured_io,ClientPid,{Detail,Str}}, St) ->
+    output(Detail, Str, ClientPid, ClientPid, St),
+    {noreply,St};
+handle_info({printout,Detail,Format,Args}, St) ->
+    Str = io_lib:format(Format, Args),
+    output(Detail, Str, internal, none, St),
+    {noreply,St};
+handle_info(Msg, #st{tc_supervisor=Pid}=St) when is_pid(Pid) ->
+    %% The process overseeing the testcase process also used to be
+    %% the group leader; thus, it is widely expected that it can be
+    %% reached by sending a message to the group leader. Therefore
+    %% we'll need to forward any non-recognized messaged to the test
+    %% case supervisor.
+    Pid ! Msg,
+    {noreply,St};
+handle_info(_Msg, #st{}=St) ->
+    %% There is no known supervisor process. Ignore this message.
+    {noreply,St}.
+
+terminate(_, _) ->
+    ok.
+
+do_set_props([{levels,Levels}|Ps], St) ->
+    do_set_props(Ps, St#st{levels=Levels});
+do_set_props([{auto_nl,AutoNL}|Ps], St) ->
+    do_set_props(Ps, St#st{auto_nl=AutoNL});
+do_set_props([{reject_io_reqs,Bool}|Ps], St) ->
+    do_set_props(Ps, St#st{reject_io=Bool});
+do_set_props([], St) -> St.
+
+io_req({put_chars,Enc,Bytes}, _, _) when Enc =:= latin1; Enc =:= unicode  ->
+    to_latin1(Enc, Bytes);
+io_req({put_chars,Encoding,Mod,Func,[Format,Args]}, _, _) ->
+    Str = Mod:Func(Format, Args),
+    to_latin1(Encoding, Str);
+io_req(_, _, _) -> passthrough.
+
+to_latin1(unicode, Str) ->
+    [if C > 255 ->
+	     io_lib:format("\\{~.8B}", [C]);
+	true ->
+	     C
+     end || C <- unicode:characters_to_list(Str, unicode)];
+to_latin1(latin1, Str) -> Str.
+
+output(Level, Str, Sender, From, St) when is_integer(Level) ->
+    case selected_by_level(Level, stdout, St) of
+	true -> output(stdout, Str, Sender, From, St);
+	false -> ok
+    end,
+    case selected_by_level(Level, major, St) of
+	true -> output(major, Str, Sender, From, St);
+	false -> ok
+    end,
+    case selected_by_level(Level, minor, St) of
+	true -> output(minor, Str, Sender, From, St);
+	false -> ok
+    end;
+output(stdout, Str, _Sender, From, St) ->
+    output_to_file(stdout, Str, From, St);
+output(html, Str, _Sender, From, St) ->
+    output_to_file(html, Str, From, St);
+output(Level, Str, Sender, From, St) when is_atom(Level) ->
+    output_to_file(Level, dress_output(Str, Sender, St), From, St).
+
+output_to_file(minor, Data0, From, #st{tc={M,F,A},minor=none}) ->
+    Data = [io_lib:format("=== ~p:~p/~p\n", [M,F,A]),Data0],
+    test_server_io:print(From, unexpected_io, Data),
+    ok;
+output_to_file(minor, Data, From, #st{minor=Fd}) ->
+    try
+	io:put_chars(Fd, Data)
+    catch
+	_:_ ->
+	    test_server_io:print(From, unexpected_io, Data)
+    end;
+output_to_file(Detail, Data, From, _) ->
+    test_server_io:print(From, Detail, Data).
+
+is_io_permitted(From, #st{reject_io=true,permit_io=P}) ->
+    gb_sets:is_member(From, P);
+is_io_permitted(_, #st{reject_io=false}) -> true.
+
+selected_by_level(Level, stdout, #st{levels={Stdout,_,_}}) ->
+    Level =< Stdout;
+selected_by_level(Level, major, #st{levels={_,Major,_}}) ->
+    Level =< Major;
+selected_by_level(Level, minor, #st{levels={_,_,Minor}}) ->
+    Level >= Minor.
+
+dress_output([$=|_]=Str, internal, _) ->
+    [Str,$\n];
+dress_output(Str, internal, _) ->
+    ["=== ",Str,$\n];
+dress_output(Str, _, #st{auto_nl=AutoNL}) ->
+    case AutoNL of
+	true -> [Str,$\n];
+	false -> Str
+    end.
diff --git a/lib/test_server/src/test_server_io.erl b/lib/test_server/src/test_server_io.erl
new file mode 100644
index 0000000000..abdfb71241
--- /dev/null
+++ b/lib/test_server/src/test_server_io.erl
@@ -0,0 +1,315 @@
+%%
+%% %CopyrightBegin%
+%%
+%% Copyright Ericsson AB 2012. 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
+%% compliance with the License. You should have received a copy of the
+%% Erlang Public License along with this software. If not, it can be
+%% retrieved online at http://www.erlang.org/.
+%%
+%% Software distributed under the License is distributed on an "AS IS"
+%% basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
+%% the License for the specific language governing rights and limitations
+%% under the License.
+%%
+%% %CopyrightEnd%
+%%
+%% This module implements a process with the registered name 'test_server_io',
+%% which has two main responsibilities:
+%%
+%%   * Manage group leader processes (see the test_server_gl module)
+%%   for test cases. A group_leader process is obtained by calling
+%%   get_gl/1. Group leader processes will be kept alive as along as
+%%   the 'test_server_io' process is alive.
+%%
+%%   * Handle output to the common log files (stdout, major, html,
+%%   unexpected_io).
+%%
+
+-module(test_server_io).
+-export([start_link/0,stop/0,get_gl/1,set_fd/2,
+	 start_transaction/0,end_transaction/0,print_buffered/1,print/3,
+	 set_footer/1,set_job_name/1,set_gl_props/1]).
+
+-export([init/1,handle_call/3,handle_info/2,terminate/2]).
+
+-record(st, {fds,				%Singleton fds (gb_tree)
+	     shared_gl :: pid(),		%Shared group leader
+	     gls,				%Group leaders (gb_set)
+	     io_buffering=false,		%I/O buffering
+	     buffered,				%Buffered I/O requests
+	     html_footer,			%HTML footer
+	     job_name,				%Name of current job.
+	     gl_props,				%Properties for GL.
+	     stopping
+	    }).
+
+start_link() ->
+    case gen_server:start_link({local,?MODULE}, ?MODULE, [], []) of
+	{ok,Pid} ->
+	    {ok,Pid};
+	Other ->
+	    Other
+    end.
+
+stop() ->
+    OldGL = group_leader(),
+    group_leader(self(), self()),
+    req(stop),
+    group_leader(OldGL, self()),
+    ok.
+
+%% get_gl(Shared) -> Pid
+%%  Shared = boolean()
+%%  Pid = pid()
+%%
+%%  Return a group leader (a process using the test_server_gl module).
+%%  If Shared is true, the shared group leader is returned (suitable for
+%%  running sequential test cases), otherwise a new group leader process
+%%  is spawned. Group leader processes will live until they are garbaged
+%%  collected by a call to gc/0.
+
+get_gl(Shared) when is_boolean(Shared) ->
+    req({get_gl,Shared}).
+
+%% set_fd(Tag, Fd) -> ok.
+%%  Tag = major | html | unexpected_io
+%%  Fd = a file descriptor (as returned by file:open/2)
+%%
+%%  Associate a file descriptor with the given Tag. This
+%%  Tag can later be used in when calling to print/3.
+
+set_fd(Tag, Fd) ->
+    req({set_fd,Tag,Fd}).
+
+%% start_transaction()
+%%
+%%  Subsequent calls to print/3 from the process executing start_transaction/0
+%%  will cause the messages to be buffered instead of printed directly.
+
+start_transaction() ->
+    req({start_transaction,self()}).
+
+%% end_transaction()
+%%
+%%  End the transaction started by start_transaction/0. Subsequent calls to
+%%  print/3 will cause the message to be printed directory.
+
+end_transaction() ->
+    req({end_transaction,self()}).
+
+%% print(From, Tag, Msg)
+%%  From = pid()
+%%  Tag = stdout, or any tag that has been registered using set_fd/2
+%%  Msg = string or iolist
+%%
+%%  Either print Msg to the file identified by Tag, or buffer the message
+%%  start_transaction/0 has been called from the process From.
+%%
+%%  NOTE: The tags have various special meanings. For example, 'html'
+%%  is assumed to be a HTML file.
+
+print(From, Tag, Msg) ->
+    req({print,From,Tag,Msg}).
+
+%% print_buffered(Pid)
+%%  Pid = pid()
+%%
+%%  Print all messages buffered in the *first* transaction buffered for Pid.
+%%  (If start_transaction/0 and end_transaction/0 has been called N times,
+%%  print_buffered/1 must be called N times to print all transactions.)
+
+print_buffered(Pid) ->
+    req({print_buffered,Pid}).
+
+%% set_footer(IoData)
+%%
+%%  Set a footer for the file associated with the 'html' tag.
+%%  It will be used by print/3 to print a footer for the HTML file.
+
+set_footer(Footer) ->
+    req({set_footer,Footer}).
+
+%% set_job_name(Name)
+%%  Set a name for the currently running job. The name will be used
+%%  when printing to 'stdout'.
+%%
+set_job_name(Name) ->
+    req({set_job_name,Name}).
+
+%% set_gl_props(PropList)
+%%  Set properties for group leader processes. When a group_leader process
+%%  is created, test_server_gl:set_props(PropList) will be called.
+
+set_gl_props(PropList) ->
+    req({set_gl_props,PropList}).
+
+
+%%% Internal functions.
+
+init([]) ->
+    process_flag(trap_exit, true),
+    Empty = gb_trees:empty(),
+    {ok,Shared} = test_server_gl:start_link(),
+    {ok,#st{fds=Empty,shared_gl=Shared,gls=gb_sets:empty(),
+	    io_buffering=gb_sets:empty(),
+	    buffered=Empty,
+	    html_footer="</body>\n</html>\n",
+	    job_name="<name not set>",
+	    gl_props=[]}}.
+
+req(Req) ->
+    gen_server:call(?MODULE, Req, infinity).
+
+handle_call({get_gl,false}, _From, #st{gls=Gls,gl_props=Props}=St) ->
+    {ok,Pid} = test_server_gl:start_link(),
+    test_server_gl:set_props(Pid, Props),
+    {reply,Pid,St#st{gls=gb_sets:insert(Pid, Gls)}};
+handle_call({get_gl,true}, _From, #st{shared_gl=Shared}=St) ->
+    {reply,Shared,St};
+handle_call({set_fd,Tag,Fd}, _From, #st{fds=Fds0}=St) ->
+    Fds = gb_trees:enter(Tag, Fd, Fds0),
+    {reply,ok,St#st{fds=Fds}};
+handle_call({start_transaction,Pid}, _From, #st{io_buffering=Buffer0,
+						buffered=Buf0}=St) ->
+    Buf = case gb_trees:is_defined(Pid, Buf0) of
+	      false -> gb_trees:insert(Pid, queue:new(), Buf0);
+	      true -> Buf0
+	  end,
+    Buffer = gb_sets:add(Pid, Buffer0),
+    {reply,ok,St#st{io_buffering=Buffer,buffered=Buf}};
+handle_call({print,From,Tag,Str}, _From, St0) ->
+    St = output(From, Tag, Str, St0),
+    {reply,ok,St};
+handle_call({end_transaction,Pid}, _From, #st{io_buffering=Buffer0,
+					      buffered=Buffered0}=St0) ->
+    Q0 = gb_trees:get(Pid, Buffered0),
+    Q = queue:in(eot, Q0),
+    Buffered = gb_trees:update(Pid, Q, Buffered0),
+    Buffer = gb_sets:delete_any(Pid, Buffer0),
+    St = St0#st{io_buffering=Buffer,buffered=Buffered},
+    {reply,ok,St};
+handle_call({print_buffered,Pid}, _From, #st{buffered=Buffered0}=St0) ->
+    Q0 = gb_trees:get(Pid, Buffered0),
+    Q = do_print_buffered(Q0, St0),
+    Buffered = gb_trees:update(Pid, Q, Buffered0),
+    St = St0#st{buffered=Buffered},
+    {reply,ok,St};
+handle_call({set_footer,Footer}, _From, St) ->
+    {reply,ok,St#st{html_footer=Footer}};
+handle_call({set_job_name,Name}, _From, St) ->
+    {reply,ok,St#st{job_name=Name}};
+handle_call({set_gl_props,Props}, _From, #st{shared_gl=Shared}=St) ->
+    test_server_gl:set_props(Shared, Props),
+    {reply,ok,St#st{gl_props=Props}};
+handle_call(stop, From, #st{shared_gl=SGL,gls=Gls0}=St0) ->
+    St = St0#st{gls=gb_sets:insert(SGL, Gls0),stopping=From},
+    gc(St),
+    %% Give the users of the surviving group leaders some
+    %% time to finish.
+    erlang:send_after(2000, self(), stop_group_leaders),
+    {noreply,St}.
+
+handle_info({'EXIT',Pid,normal}, #st{gls=Gls0,stopping=From}=St) ->
+    Gls = gb_sets:delete_any(Pid, Gls0),
+    case gb_sets:is_empty(Gls) andalso stopping =/= undefined of
+	true ->
+	    %% No more group leaders left.
+	    gen_server:reply(From, ok),
+	    {stop,normal,St#st{gls=Gls,stopping=undefined}};
+	false ->
+	    %% Wait for more group leaders to finish.
+	    {noreply,St#st{gls=Gls}}
+    end;
+handle_info({'EXIT',_Pid,Reason}, _St) ->
+    exit(Reason);
+handle_info(stop_group_leaders, #st{gls=Gls}=St) ->
+    %% Stop the remaining group leaders.
+    [test_server_gl:stop(GL) || GL <- gb_sets:to_list(Gls)],
+    erlang:send_after(2000, self(), kill_group_leaders),
+    {noreply,St};
+handle_info(kill_group_leaders, #st{gls=Gls,stopping=From}=St) ->
+    [exit(GL, kill) || GL <- gb_sets:to_list(Gls)],
+    gen_server:reply(From, ok),
+    {stop,normal,St};
+handle_info(Other, St) ->
+    io:format("Ignoring: ~p\n", [Other]),
+    {noreply,St}.
+
+terminate(_, _) ->
+    ok.
+
+output(From, Tag, Str, #st{io_buffering=Buffered,buffered=Buf0}=St) ->
+    case gb_sets:is_member(From, Buffered) of
+	false ->
+	    do_output(Tag, Str, St),
+	    St;
+	true ->
+	    Q0 = gb_trees:get(From, Buf0),
+	    Q = queue:in({Tag,Str}, Q0),
+	    Buf = gb_trees:update(From, Q, Buf0),
+	    St#st{buffered=Buf}
+    end.
+
+do_output(stdout, Str0, #st{job_name=Name}) ->
+    Str = io_lib:format("Testing ~s: ~s\n", [Name,Str0]),
+    io:put_chars(Str);
+do_output(Tag, Str, #st{fds=Fds}=St) ->
+    case gb_trees:lookup(Tag, Fds) of
+	none ->
+	    S = io_lib:format("\n*** ERROR: ~p, line ~p: No known '~p' log file\n",
+			      [?MODULE,?LINE,Tag]),
+	    do_output(stdout, [S,Str], St);
+	{value,Fd} ->
+	    try
+		io:put_chars(Fd, Str),
+		case Tag of
+		    html -> finalise_table(Fd, St);
+		    _ -> ok
+		end
+	    catch _:Error ->
+		    S = io_lib:format("\n*** ERROR: ~p, line ~p: Error writing to "
+				      "log file '~p': ~p\n",
+				      [?MODULE,?LINE,Tag,Error]),
+		    do_output(stdout, [S,Str], St)
+	    end
+    end.
+
+finalise_table(Fd, #st{html_footer=Footer}) ->
+    case file:position(Fd, {cur,0}) of
+	{ok,Pos} ->
+	    %% We are writing to a seekable file.  Finalise so
+	    %% we get complete valid (and viewable) HTML code.
+	    %% Then rewind to overwrite the finalising code.
+	    io:put_chars(Fd, ["\n</table>\n",Footer]),
+	    file:position(Fd, Pos);
+	{error,epipe} ->
+	    %% The file is not seekable.  We cannot erase what
+	    %% we've already written --- so the reader will
+	    %% have to wait until we're done.
+	    ok
+    end.
+
+do_print_buffered(Q0, St) ->
+    Item = queue:get(Q0),
+    Q = queue:drop(Q0),
+    case Item of
+	eot ->
+	    Q;
+	{Tag,Str} ->
+	    do_output(Tag, Str, St),
+	    do_print_buffered(Q, St)
+    end.
+
+gc(#st{gls=Gls0}) ->
+    InUse0 = [begin
+		  {group_leader,GL} = process_info(P, group_leader),
+		  GL
+	      end || P <- processes()],
+    InUse = ordsets:from_list(InUse0),
+    Gls = gb_sets:to_list(Gls0),
+    NotUsed = ordsets:subtract(Gls, InUse),
+    [test_server_gl:stop(Pid) || Pid <- NotUsed],
+    ok.