The R13B03 release.OTP_R13B03

1 files changed, 614 insertions, 0 deletions

diff --git a/lib/kernel/src/user_drv.erl b/lib/kernel/src/user_drv.erl
new file mode 100644
index 0000000000..c34f2ddeb0
--- /dev/null
+++ b/lib/kernel/src/user_drv.erl
@@ -0,0 +1,614 @@
+%%
+%% %CopyrightBegin%
+%% 
+%% Copyright Ericsson AB 1996-2009. 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%
+%%
+-module(user_drv).
+
+%% Basic interface to a port.
+
+-export([start/0,start/1,start/2,start/3,server/2,server/3]).
+
+-export([interfaces/1]).
+
+-define(OP_PUTC,0).
+-define(OP_MOVE,1).
+-define(OP_INSC,2).
+-define(OP_DELC,3).
+-define(OP_BEEP,4).
+% Control op
+-define(CTRL_OP_GET_WINSIZE,100).
+-define(CTRL_OP_GET_UNICODE_STATE,101).
+-define(CTRL_OP_SET_UNICODE_STATE,102).
+
+%% start()
+%% start(ArgumentList)
+%% start(PortName, Shell)
+%% start(InPortName, OutPortName, Shell)
+%%  Start the user driver server. The arguments to start/1 are slightly
+%%  strange as this may be called both at start up from the command line
+%%  and explicitly from other code.
+
+-spec start() -> pid().
+
+start() ->					%Default line editing shell
+    spawn(user_drv, server, ['tty_sl -c -e',{shell,start,[init]}]).
+
+start([Pname]) ->
+    spawn(user_drv, server, [Pname,{shell,start,[init]}]);
+start([Pname|Args]) ->
+    spawn(user_drv, server, [Pname|Args]);
+start(Pname) ->
+    spawn(user_drv, server, [Pname,{shell,start,[init]}]).
+
+start(Pname, Shell) ->
+    spawn(user_drv, server, [Pname,Shell]).
+
+start(Iname, Oname, Shell) ->
+    spawn(user_drv, server, [Iname,Oname,Shell]).
+
+
+%% Return the pid of the active group process.
+%% Note: We can't ask the user_drv process for this info since it
+%% may be busy waiting for data from the port.
+
+-spec interfaces(pid()) -> [{'current_group', pid()}].
+
+interfaces(UserDrv) ->
+    case process_info(UserDrv, dictionary) of
+	{dictionary,Dict} ->
+	    case lists:keysearch(current_group, 1, Dict) of
+		{value,Gr={_,Group}} when is_pid(Group) ->
+		    [Gr];
+		_ ->
+		    []
+	    end;
+	_ ->
+	    []
+    end.
+
+%% server(Pid, Shell)
+%% server(Pname, Shell)
+%% server(Iname, Oname, Shell)
+%%  The initial calls to run the user driver. These start the port(s)
+%%  then call server1/3 to set everything else up.
+
+server(Pid, Shell) when is_pid(Pid) ->
+    server1(Pid, Pid, Shell);
+server(Pname, Shell) ->
+    process_flag(trap_exit, true),
+    case catch open_port({spawn,Pname}, [eof]) of
+	{'EXIT', _} ->
+	    %% Let's try a dumb user instead
+	    user:start();
+	Port ->
+	    server1(Port, Port, Shell)
+    end.
+
+server(Iname, Oname, Shell) ->
+    process_flag(trap_exit, true),
+    case catch open_port({spawn,Iname}, [eof]) of
+	{'EXIT', _} -> %% It might be a dumb terminal lets start dumb user
+	    user:start();
+	Iport ->
+	    Oport = open_port({spawn,Oname}, [eof]),
+	    server1(Iport, Oport, Shell)
+    end.
+
+server1(Iport, Oport, Shell) ->
+    put(eof, false),
+    %% Start user and initial shell.
+    User = start_user(),
+    Gr1 = gr_add_cur(gr_new(), User, {}),
+
+    {Curr,Shell1} =
+	case init:get_argument(remsh) of
+	    {ok,[[Node]]} ->
+		RShell = {list_to_atom(Node),shell,start,[]},
+		RGr = group:start(self(), RShell),
+		{RGr,RShell};
+	    E when E =:= error ; E =:= {ok,[[]]} ->
+		{group:start(self(), Shell),Shell}
+	end,
+
+    put(current_group, Curr),
+    Gr = gr_add_cur(Gr1, Curr, Shell1),
+    %% Print some information.
+    io_request({put_chars, unicode,
+		flatten(io_lib:format("~s\n",
+				      [erlang:system_info(system_version)]))},
+	       Iport, Oport),
+    %% Enter the server loop.
+    server_loop(Iport, Oport, Curr, User, Gr).
+
+%% start_user()
+%%  Start a group leader process and register it as 'user', unless,
+%%  of course, a 'user' already exists.
+
+start_user() ->
+    case whereis(user_drv) of
+	undefined ->
+	    register(user_drv, self());
+	_ ->
+	    ok
+    end,
+    case whereis(user) of
+	undefined ->
+	    User = group:start(self(), {}),
+	    register(user, User),
+	    User;
+	User ->
+	    User
+    end.
+   
+server_loop(Iport, Oport, User, Gr) ->
+    Curr = gr_cur_pid(Gr),
+    put(current_group, Curr),
+    server_loop(Iport, Oport, Curr, User, Gr).
+
+server_loop(Iport, Oport, Curr, User, Gr) ->
+    receive
+	{Iport,{data,Bs}} ->
+	    BsBin = list_to_binary(Bs),
+	    Unicode = unicode:characters_to_list(BsBin,utf8),
+	    port_bytes(Unicode, Iport, Oport, Curr, User, Gr);
+	{Iport,eof} ->
+	    Curr ! {self(),eof},
+	    server_loop(Iport, Oport, Curr, User, Gr);
+	{User,Req} ->	% never block from user!
+	    io_request(Req, Iport, Oport),
+	    server_loop(Iport, Oport, Curr, User, Gr);
+	{Curr,tty_geometry} ->
+	    Curr ! {self(),tty_geometry,get_tty_geometry(Iport)},
+	    server_loop(Iport, Oport, Curr, User, Gr);
+	{Curr,get_unicode_state} ->
+	    Curr ! {self(),get_unicode_state,get_unicode_state(Iport)},
+	    server_loop(Iport, Oport, Curr, User, Gr);
+	{Curr,set_unicode_state, Bool} ->
+	    Curr ! {self(),set_unicode_state,set_unicode_state(Iport,Bool)},
+	    server_loop(Iport, Oport, Curr, User, Gr);
+	{Curr,Req} ->
+	    io_request(Req, Iport, Oport),
+	    server_loop(Iport, Oport, Curr, User, Gr);
+	{'EXIT',Iport,_R} ->
+	    server_loop(Iport, Oport, Curr, User, Gr);
+	{'EXIT',Oport,_R} ->
+	    server_loop(Iport, Oport, Curr, User, Gr);
+	{'EXIT',User,_R} ->			% keep 'user' alive
+	    NewU = start_user(),
+	    server_loop(Iport, Oport, Curr, NewU, gr_set_num(Gr, 1, NewU, {}));
+	{'EXIT',Pid,R} ->			% shell and group leader exit
+	    case gr_cur_pid(Gr) of
+		Pid when R =/= die ,
+			 R =/= terminated  ->	% current shell exited
+		    if R =/= normal ->
+			    io_requests([{put_chars,unicode,"*** ERROR: "}], Iport, Oport);
+		       true -> % exit not caused by error
+			    io_requests([{put_chars,unicode,"*** "}], Iport, Oport)
+		    end,
+		    io_requests([{put_chars,unicode,"Shell process terminated! "}], Iport, Oport),
+		    Gr1 = gr_del_pid(Gr, Pid),		    
+		    case gr_get_info(Gr, Pid) of
+			{Ix,{shell,start,Params}} -> % 3-tuple == local shell
+			    io_requests([{put_chars,unicode,"***\n"}], Iport, Oport),	    
+			    %% restart group leader and shell, same index
+			    Pid1 = group:start(self(), {shell,start,Params}),
+			    {ok,Gr2} = gr_set_cur(gr_set_num(Gr1, Ix, Pid1, 
+							     {shell,start,Params}), Ix),
+			    put(current_group, Pid1),
+			    server_loop(Iport, Oport, Pid1, User, Gr2);
+			_ -> % remote shell
+			    io_requests([{put_chars,unicode,"(^G to start new job) ***\n"}],
+					Iport, Oport),	    
+			    server_loop(Iport, Oport, Curr, User, Gr1)
+		    end;
+		_ ->				% not current, just remove it
+		    server_loop(Iport, Oport, Curr, User, gr_del_pid(Gr, Pid))
+	    end;
+	_X ->
+	    %% Ignore unknown messages.
+	    server_loop(Iport, Oport, Curr, User, Gr)
+    end.
+
+%% port_bytes(Bytes, InPort, OutPort, CurrentProcess, UserProcess, Group)
+%%  Check the Bytes from the port to see if it contains a ^G. If so,
+%%  either escape to switch_loop or restart the shell. Otherwise send 
+%%  the bytes to Curr.
+
+port_bytes([$\^G|_Bs], Iport, Oport, _Curr, User, Gr) ->
+    handle_escape(Iport, Oport, User, Gr);
+
+port_bytes([$\^C|_Bs], Iport, Oport, Curr, User, Gr) ->
+    interrupt_shell(Iport, Oport, Curr, User, Gr);
+
+port_bytes([B], Iport, Oport, Curr, User, Gr) ->
+    Curr ! {self(),{data,[B]}},
+    server_loop(Iport, Oport, Curr, User, Gr);
+port_bytes(Bs, Iport, Oport, Curr, User, Gr) ->
+    case member($\^G, Bs) of
+	true ->
+	    handle_escape(Iport, Oport, User, Gr);
+	false ->
+	    Curr ! {self(),{data,Bs}},
+	    server_loop(Iport, Oport, Curr, User, Gr)
+    end.
+
+interrupt_shell(Iport, Oport, Curr, User, Gr) ->
+    case gr_get_info(Gr, Curr) of
+	undefined -> 
+	    ok;					% unknown
+	_ ->
+	    exit(Curr, interrupt)
+    end,
+    server_loop(Iport, Oport, Curr, User, Gr).
+
+handle_escape(Iport, Oport, User, Gr) ->
+    case application:get_env(stdlib, shell_esc) of
+	{ok,abort} ->
+	    Pid = gr_cur_pid(Gr),
+	    exit(Pid, die),
+	    Gr1 =
+		case gr_get_info(Gr, Pid) of
+		    {_Ix,{}} ->			% no shell
+			Gr;
+		    _ ->
+			receive {'EXIT',Pid,_} ->
+				gr_del_pid(Gr, Pid)
+			after 1000 ->
+				Gr
+			end
+		end,
+	    Pid1 = group:start(self(), {shell,start,[]}),
+	    io_request({put_chars,unicode,"\n"}, Iport, Oport),
+	    server_loop(Iport, Oport, User, 
+			gr_add_cur(Gr1, Pid1, {shell,start,[]}));
+
+	_ ->					% {ok,jcl} | undefined
+	    io_request({put_chars,unicode,"\nUser switch command\n"}, Iport, Oport),
+	    server_loop(Iport, Oport, User, switch_loop(Iport, Oport, Gr))
+    end.
+
+switch_loop(Iport, Oport, Gr) ->
+    Line = get_line(edlin:start(" --> "), Iport, Oport),
+    switch_cmd(erl_scan:string(Line), Iport, Oport, Gr).
+
+switch_cmd({ok,[{atom,_,c},{integer,_,I}],_}, Iport, Oport, Gr0) ->
+    case gr_set_cur(Gr0, I) of
+	{ok,Gr} -> Gr;
+	undefined -> unknown_group(Iport, Oport, Gr0)
+    end;
+switch_cmd({ok,[{atom,_,c}],_}, Iport, Oport, Gr) ->
+    case gr_get_info(Gr, gr_cur_pid(Gr)) of
+	undefined -> 
+	    unknown_group(Iport, Oport, Gr);
+	_ ->
+	    Gr
+    end;
+switch_cmd({ok,[{atom,_,i},{integer,_,I}],_}, Iport, Oport, Gr) ->
+    case gr_get_num(Gr, I) of
+	{pid,Pid} ->
+	    exit(Pid, interrupt),
+	    switch_loop(Iport, Oport, Gr);
+	undefined ->
+	    unknown_group(Iport, Oport, Gr)
+    end;
+switch_cmd({ok,[{atom,_,i}],_}, Iport, Oport, Gr) ->
+    Pid = gr_cur_pid(Gr),
+    case gr_get_info(Gr, Pid) of
+	undefined -> 
+	    unknown_group(Iport, Oport, Gr);
+	_ ->
+	    exit(Pid, interrupt),
+	    switch_loop(Iport, Oport, Gr)
+    end;
+switch_cmd({ok,[{atom,_,k},{integer,_,I}],_}, Iport, Oport, Gr) ->
+    case gr_get_num(Gr, I) of
+	{pid,Pid} ->
+	    exit(Pid, die),
+	    case gr_get_info(Gr, Pid) of
+		{_Ix,{}} ->			% no shell
+		    switch_loop(Iport, Oport, Gr);
+		_ ->
+		    Gr1 = 
+			receive {'EXIT',Pid,_} ->
+				gr_del_pid(Gr, Pid)
+			after 1000 ->
+				Gr
+			end,
+		    switch_loop(Iport, Oport, Gr1)
+	    end;
+	undefined ->
+	    unknown_group(Iport, Oport, Gr)
+    end;
+switch_cmd({ok,[{atom,_,k}],_}, Iport, Oport, Gr) ->
+    Pid = gr_cur_pid(Gr),
+    Info = gr_get_info(Gr, Pid), 
+    case Info of
+	undefined ->
+	    unknown_group(Iport, Oport, Gr);
+	{_Ix,{}} ->				% no shell
+	    switch_loop(Iport, Oport, Gr);
+	_ ->
+	    exit(Pid, die),
+	    Gr1 = 
+		receive {'EXIT',Pid,_} ->
+			gr_del_pid(Gr, Pid)
+		after 1000 ->
+			Gr
+		end,
+	    switch_loop(Iport, Oport, Gr1)
+    end;
+switch_cmd({ok,[{atom,_,j}],_}, Iport, Oport, Gr) ->
+    io_requests(gr_list(Gr), Iport, Oport),
+    switch_loop(Iport, Oport, Gr);
+switch_cmd({ok,[{atom,_,s},{atom,_,Shell}],_}, Iport, Oport, Gr0) ->
+    Pid = group:start(self(), {Shell,start,[]}),
+    Gr = gr_add_cur(Gr0, Pid, {Shell,start,[]}),
+    switch_loop(Iport, Oport, Gr);
+switch_cmd({ok,[{atom,_,s}],_}, Iport, Oport, Gr0) ->
+    Pid = group:start(self(), {shell,start,[]}),
+    Gr = gr_add_cur(Gr0, Pid, {shell,start,[]}),
+    switch_loop(Iport, Oport, Gr);
+switch_cmd({ok,[{atom,_,r}],_}, Iport, Oport, Gr0) ->
+    case is_alive() of
+	true ->
+	    Node = pool:get_node(),
+	    Pid = group:start(self(), {Node,shell,start,[]}),
+	    Gr = gr_add_cur(Gr0, Pid, {Node,shell,start,[]}),
+	    switch_loop(Iport, Oport, Gr);
+	false ->
+	    io_request({put_chars,unicode,"Not alive\n"}, Iport, Oport),
+	    switch_loop(Iport, Oport, Gr0)
+    end;
+switch_cmd({ok,[{atom,_,r},{atom,_,Node}],_}, Iport, Oport, Gr0) ->
+    Pid = group:start(self(), {Node,shell,start,[]}),
+    Gr = gr_add_cur(Gr0, Pid, {Node,shell,start,[]}),
+    switch_loop(Iport, Oport, Gr);
+switch_cmd({ok,[{atom,_,r},{atom,_,Node},{atom,_,Shell}],_},
+	   Iport, Oport, Gr0) ->
+    Pid = group:start(self(), {Node,Shell,start,[]}),
+    Gr = gr_add_cur(Gr0, Pid, {Node,Shell,start,[]}),
+    switch_loop(Iport, Oport, Gr);
+switch_cmd({ok,[{atom,_,q}],_}, Iport, Oport, Gr) ->
+    case erlang:system_info(break_ignored) of
+	true ->					% noop
+	    io_request({put_chars,unicode,"Unknown command\n"}, Iport, Oport),
+	    switch_loop(Iport, Oport, Gr);
+	false ->
+	    halt()
+    end;
+switch_cmd({ok,[{atom,_,h}],_}, Iport, Oport, Gr) ->
+    list_commands(Iport, Oport),
+    switch_loop(Iport, Oport, Gr);
+switch_cmd({ok,[{'?',_}],_}, Iport, Oport, Gr) ->
+    list_commands(Iport, Oport),
+    switch_loop(Iport, Oport, Gr);
+switch_cmd({ok,[],_}, Iport, Oport, Gr) ->
+    switch_loop(Iport, Oport, Gr);
+switch_cmd({ok,_Ts,_}, Iport, Oport, Gr) ->
+    io_request({put_chars,unicode,"Unknown command\n"}, Iport, Oport),
+    switch_loop(Iport, Oport, Gr);
+switch_cmd(_Ts, Iport, Oport, Gr) ->
+    io_request({put_chars,unicode,"Illegal input\n"}, Iport, Oport),
+    switch_loop(Iport, Oport, Gr).
+
+unknown_group(Iport, Oport, Gr) ->
+    io_request({put_chars,unicode,"Unknown job\n"}, Iport, Oport),
+    switch_loop(Iport, Oport, Gr).
+
+list_commands(Iport, Oport) ->
+    QuitReq = case erlang:system_info(break_ignored) of
+		  true -> 
+		      [];
+		  false ->
+		      [{put_chars,unicode,"  q        - quit erlang\n"}]
+	      end,
+    io_requests([{put_chars, unicode,"  c [nn]            - connect to job\n"},
+		 {put_chars, unicode,"  i [nn]            - interrupt job\n"},
+		 {put_chars, unicode,"  k [nn]            - kill job\n"},
+		 {put_chars, unicode,"  j                 - list all jobs\n"},
+		 {put_chars, unicode,"  s [shell]         - start local shell\n"},
+		 {put_chars, unicode,"  r [node [shell]]  - start remote shell\n"}] ++
+		QuitReq ++
+		[{put_chars, unicode,"  ? | h             - this message\n"}],
+		Iport, Oport).
+
+get_line({done,Line,_Rest,Rs}, Iport, Oport) ->
+    io_requests(Rs, Iport, Oport),
+    Line;
+get_line({undefined,_Char,Cs,Cont,Rs}, Iport, Oport) ->
+    io_requests(Rs, Iport, Oport),
+    io_request(beep, Iport, Oport),
+    get_line(edlin:edit_line(Cs, Cont), Iport, Oport);
+get_line({What,Cont0,Rs}, Iport, Oport) ->
+    io_requests(Rs, Iport, Oport),
+    receive
+	{Iport,{data,Cs}} ->
+	    get_line(edlin:edit_line(Cs, Cont0), Iport, Oport);
+	{Iport,eof} ->
+	    get_line(edlin:edit_line(eof, Cont0), Iport, Oport)
+    after
+	get_line_timeout(What) ->
+	    get_line(edlin:edit_line([], Cont0), Iport, Oport)
+    end.
+
+get_line_timeout(blink) -> 1000;
+get_line_timeout(more_chars) -> infinity.
+
+% Let driver report window geometry,
+% definitely outside of the common interface
+get_tty_geometry(Iport) ->
+    case (catch port_control(Iport,?CTRL_OP_GET_WINSIZE,[])) of
+	List when length(List) =:= 8 -> 
+	    <<W:32/native,H:32/native>> = list_to_binary(List),
+	    {W,H};
+	_ ->
+	    error
+    end.
+get_unicode_state(Iport) ->
+    case (catch port_control(Iport,?CTRL_OP_GET_UNICODE_STATE,[])) of
+	[Int] when Int > 0 -> 
+	    true;
+	[Int] when Int =:= 0 ->
+	    false;
+	_ ->
+	    error
+    end.
+
+set_unicode_state(Iport, Bool) ->
+    Data = case Bool of
+	       true -> [1];
+	       false -> [0]
+	   end,
+    case (catch port_control(Iport,?CTRL_OP_SET_UNICODE_STATE,Data)) of
+	[Int] when Int > 0 -> 
+	    {unicode, utf8};
+	[Int] when Int =:= 0 ->
+	    {unicode, false};
+	_ ->
+	    error
+    end.
+
+%% 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.
+
+io_requests([R|Rs], Iport, Oport) ->
+    io_request(R, Iport, Oport),
+    io_requests(Rs, Iport, Oport);
+io_requests([], _Iport, _Oport) ->
+    ok.
+
+put_int16(N, Tail) ->
+    [(N bsr 8)band 255,N band 255|Tail].
+
+%% gr_new()
+%% gr_get_num(Group, Index)
+%% gr_get_info(Group, Pid)
+%% gr_add_cur(Group, Pid, Shell)
+%% gr_set_cur(Group, Index)
+%% gr_cur_pid(Group)
+%% gr_del_pid(Group, Pid)
+%%  Manage the group list. The group structure has the form:
+%%	{NextIndex,CurrIndex,CurrPid,GroupList}
+%%
+%%  where each element in the group list is:
+%%	{Index,GroupPid,Shell}
+
+gr_new() ->
+    {0,0,none,[]}.
+
+gr_get_num({_Next,_CurI,_CurP,Gs}, I) ->
+    gr_get_num1(Gs, I).
+
+gr_get_num1([{I,_Pid,{}}|_Gs], I) ->
+    undefined;
+gr_get_num1([{I,Pid,_S}|_Gs], I) ->
+    {pid,Pid};
+gr_get_num1([_G|Gs], I) ->
+    gr_get_num1(Gs, I);
+gr_get_num1([], _I) ->
+    undefined.
+
+gr_get_info({_Next,_CurI,_CurP,Gs}, Pid) ->
+    gr_get_info1(Gs, Pid).
+
+gr_get_info1([{I,Pid,S}|_Gs], Pid) ->
+    {I,S};
+gr_get_info1([_G|Gs], I) ->
+    gr_get_info1(Gs, I);
+gr_get_info1([], _I) ->
+    undefined.
+
+gr_add_cur({Next,_CurI,_CurP,Gs}, Pid, Shell) ->
+    {Next+1,Next,Pid,append(Gs, [{Next,Pid,Shell}])}.
+
+gr_set_cur({Next,_CurI,_CurP,Gs}, I) ->
+    case gr_get_num1(Gs, I) of
+	{pid,Pid} -> {ok,{Next,I,Pid,Gs}};
+	undefined -> undefined
+    end.
+
+gr_set_num({Next,CurI,CurP,Gs}, I, Pid, Shell) ->
+    {Next,CurI,CurP,gr_set_num1(Gs, I, Pid, Shell)}.
+
+gr_set_num1([{I,_Pid,_Shell}|Gs], I, NewPid, NewShell) ->
+    [{I,NewPid,NewShell}|Gs];
+gr_set_num1([{I,Pid,Shell}|Gs], NewI, NewPid, NewShell) when NewI > I ->
+    [{I,Pid,Shell}|gr_set_num1(Gs, NewI, NewPid, NewShell)];
+gr_set_num1(Gs, NewI, NewPid, NewShell) ->
+    [{NewI,NewPid,NewShell}|Gs].
+
+gr_del_pid({Next,CurI,CurP,Gs}, Pid) ->
+    {Next,CurI,CurP,gr_del_pid1(Gs, Pid)}.
+
+gr_del_pid1([{_I,Pid,_S}|Gs], Pid) ->
+    Gs;
+gr_del_pid1([G|Gs], Pid) ->
+    [G|gr_del_pid1(Gs, Pid)];
+gr_del_pid1([], _Pid) ->
+    [].
+
+gr_cur_pid({_Next,_CurI,CurP,_Gs}) ->
+    CurP.
+
+gr_list({_Next,CurI,_CurP,Gs}) ->
+    gr_list(Gs, CurI, []).
+
+gr_list([{_I,_Pid,{}}|Gs], Cur, Jobs) ->
+    gr_list(Gs, Cur, Jobs);
+gr_list([{Cur,_Pid,Shell}|Gs], Cur, Jobs) ->
+    gr_list(Gs, Cur, [{put_chars, unicode,flatten(io_lib:format("~4w* ~w\n", [Cur,Shell]))}|Jobs]);
+gr_list([{I,_Pid,Shell}|Gs], Cur, Jobs) ->
+    gr_list(Gs, Cur, [{put_chars, unicode,flatten(io_lib:format("~4w  ~w\n", [I,Shell]))}|Jobs]);
+gr_list([], _Cur, Jobs) ->
+    lists:reverse(Jobs).
+
+append([H|T], X) ->
+    [H|append(T, X)];
+append([], X) ->
+    X.
+
+member(X, [X|_Rest]) -> true;
+member(X, [_H|Rest]) ->
+    member(X, Rest);
+member(_X, []) -> false.
+
+flatten(List) ->
+    flatten(List, [], []).
+
+flatten([H|T], Cont, Tail) when is_list(H) ->
+    flatten(H, [T|Cont], Tail);
+flatten([H|T], Cont, Tail) ->
+    [H|flatten(T, Cont, Tail)];
+flatten([], [H|Cont], Tail) ->
+    flatten(H, Cont, Tail);
+flatten([], [], Tail) ->
+    Tail.