[stdlib, kernel] Introduce Unicode support for Erlang source files

Expect modifications, additions and corrections.

There is a kludge in file_io_server and
erl_scan:continuation_location() that's not so pleasing.

13 files changed, 1288 insertions, 758 deletions

diff --git a/lib/stdlib/src/Makefile b/lib/stdlib/src/Makefile
index 14304824d3..575a5cbe4a 100644
--- a/lib/stdlib/src/Makefile
+++ b/lib/stdlib/src/Makefile
@@ -171,6 +171,7 @@ primary_bootstrap_compiler: \
   $(BOOTSTRAP_COMPILER)/ebin/erl_scan.beam \
   $(BOOTSTRAP_COMPILER)/ebin/erl_parse.beam \
   $(BOOTSTRAP_COMPILER)/ebin/erl_lint.beam \
+  $(BOOTSTRAP_COMPILER)/ebin/io.beam \
   $(BOOTSTRAP_COMPILER)/ebin/otp_internal.beam
 
 $(BOOTSTRAP_COMPILER)/ebin/erl_parse.beam: erl_parse.yrl
diff --git a/lib/stdlib/src/epp.erl b/lib/stdlib/src/epp.erl
index 2c8d84a9e1..a0f7660ecf 100644
--- a/lib/stdlib/src/epp.erl
+++ b/lib/stdlib/src/epp.erl
@@ -23,13 +23,18 @@
 -export([open/2,open/3,open/5,close/1,format_error/1]).
 -export([scan_erl_form/1,parse_erl_form/1,macro_defs/1]).
 -export([parse_file/1, parse_file/3]).
+-export([default_encoding/0, encoding_to_string/1,
+         read_encoding/1, read_encoding/2, set_encoding/1]).
 -export([interpret_file_attribute/1]).
 -export([normalize_typed_record_fields/1,restore_typed_record_fields/1]).
 
 %%------------------------------------------------------------------------
 
+-export_type([source_encoding/0]).
+
 -type macros() :: [{atom(), term()}].
 -type epp_handle() :: pid().
+-type source_encoding() :: latin1 | utf8.
 
 %% Epp state record.
 -record(epp, {file,				%Current file
@@ -213,6 +218,173 @@ parse_file(Epp) ->
 	    [{eof,Location}]
     end.
 
+-define(DEFAULT_ENCODING, latin1).
+
+-spec default_encoding() -> source_encoding().
+
+default_encoding() ->
+    ?DEFAULT_ENCODING.
+
+-spec encoding_to_string(Encoding) -> string() when
+      Encoding :: source_encoding().
+
+encoding_to_string(latin1) -> "coding: latin-1";
+encoding_to_string(utf8) -> "coding: utf-8".
+
+-spec read_encoding(FileName) -> source_encoding() | none when
+      FileName :: file:name().
+
+read_encoding(Name) ->
+    read_encoding(Name, []).
+
+-spec read_encoding(FileName, Options) -> source_encoding() | none when
+      FileName :: file:name(),
+      Options :: [Option],
+      Option :: {in_comment_only, boolean()}.
+
+read_encoding(Name, Options) ->
+    InComment = proplists:get_value(in_comment_only, Options, true),
+    case file:open(Name, [read]) of
+        {ok,File} ->
+            try read_encoding_from_file(File, InComment)
+            after ok = file:close(File)
+            end;
+        _Error ->
+            none
+    end.
+
+-spec set_encoding(File) -> source_encoding() | none when
+      File :: io:device(). % pid(); raw files don't work
+
+set_encoding(File) ->
+    Encoding = read_encoding_from_file(File, true),
+    Enc = case Encoding of
+              none -> default_encoding();
+              Encoding -> Encoding
+          end,
+    ok = io:setopts(File, [{encoding, Enc}]),
+    Encoding.
+
+-spec read_encoding_from_file(File, InComment) -> source_encoding() | none when
+      File :: io:device(),
+      InComment :: boolean().
+
+-define(ENC_CHUNK, 32).
+-define(N_ENC_CHUNK, 16). % a total of 512 bytes
+
+read_encoding_from_file(File, InComment) ->
+    {ok, Pos0} = file:position(File, cur),
+    Opts = io:getopts(File),
+    Encoding0 = lists:keyfind(encoding, 1, Opts),
+    Binary0 = lists:keyfind(binary, 1, Opts),
+    ok = io:setopts(File, [binary, {encoding, latin1}]),
+    try
+        {B, Fun} = (reader(File, 0))(),
+        com_nl(B, Fun, 0, InComment)
+    catch
+        throw:no ->
+            none
+    after
+        {ok, Pos0} = file:position(File, Pos0),
+        ok = io:setopts(File, [Binary0, Encoding0])
+    end.
+
+reader(Fd, N) ->
+    fun() when N =:= ?N_ENC_CHUNK ->
+            throw(no);
+       () ->
+            case file:read(Fd, ?ENC_CHUNK) of
+                eof ->
+                    {<<>>, reader(Fd, N+1)};
+                {ok, Bin} ->
+                    {Bin, reader(Fd, N+1)};
+                {error, _} ->
+                    throw(no) % ignore errors
+            end
+    end.
+
+com_nl(_, _, 2, _) ->
+    throw(no);
+com_nl(B, Fun, N, false=Com) ->
+    com_c(B, Fun, N, Com);
+com_nl(B, Fun, N, true=Com) ->
+    com(B, Fun, N, Com).
+
+com(<<"\n",B/binary>>, Fun, N, Com) ->
+    com_nl(B, Fun, N+1, Com);
+com(<<"%", B/binary>>, Fun, N, Com) ->
+    com_c(B, Fun, N, Com);
+com(<<_:1/unit:8,B/binary>>, Fun, N, Com) ->
+    com(B, Fun, N, Com);
+com(<<>>, Fun, N, Com) ->
+    {B, Fun1} = Fun(),
+    com(B, Fun1, N, Com).
+
+com_c(<<"c",B/binary>>, Fun, N, Com) ->
+    com_oding(B, Fun, N, Com);
+com_c(<<"\n",B/binary>>, Fun, N, Com) ->
+    com_nl(B, Fun, N+1, Com);
+com_c(<<_:1/unit:8,B/binary>>, Fun, N, Com) ->
+    com_c(B, Fun, N, Com);
+com_c(<<>>, Fun, N, Com) ->
+    {B, Fun1} = Fun(),
+    com_c(B, Fun1, N, Com).
+
+com_oding(<<"oding",B/binary>>, Fun, N, Com) ->
+    com_sep(B, Fun, N, Com);
+com_oding(B, Fun, N, Com) when byte_size(B) >= length("oding") ->
+    com_c(B, Fun, N, Com);
+com_oding(B, Fun, N, Com) ->
+    {B1, Fun1} = Fun(),
+    com_oding(list_to_binary([B, B1]), Fun1, N, Com).
+
+com_sep(<<":",B/binary>>, Fun, N, Com) ->
+    com_space(B, Fun, N, Com);
+com_sep(<<"=",B/binary>>, Fun, N, Com) ->
+    com_space(B, Fun, N, Com);
+com_sep(<<"\s",B/binary>>, Fun, N, Com) ->
+    com_sep(B, Fun, N, Com);
+com_sep(<<>>, Fun, N, Com) ->
+    {B, Fun1} = Fun(),
+    com_sep(B, Fun1, N, Com);
+com_sep(B, Fun, N, Com) ->
+    com_c(B, Fun, N, Com).
+
+com_space(<<"\s",B/binary>>, Fun, N, Com) ->
+    com_space(B, Fun, N, Com);
+com_space(<<>>, Fun, N, Com) ->
+    {B, Fun1} = Fun(),
+    com_space(B, Fun1, N, Com);
+com_space(B, Fun, N, _Com) ->
+    com_enc(B, Fun, N, [], []).
+
+com_enc(<<C:1/unit:8,B/binary>>, Fun, N, L, Ps) when C >= $a, C =< $z;
+                                                     C >= $A, C =< $Z;
+                                                     C >= $0, C =< $9 ->
+    com_enc(B, Fun, N, [C | L], Ps);
+com_enc(<<>>, Fun, N, L, Ps) ->
+    case Fun() of
+        {<<>>, _} ->
+            com_enc_end([L | Ps]);
+        {B, Fun1} ->
+            com_enc(B, Fun1, N, L, Ps)
+    end;
+com_enc(<<"-",B/binary>>, Fun, N, L, Ps) ->
+    com_enc(B, Fun, N, [], [L | Ps]);
+com_enc(_B, _Fun, _N, L, Ps) ->
+    com_enc_end([L | Ps]).
+
+com_enc_end(Ps0) ->
+    Ps = lists:reverse([lists:reverse(string:to_lower(P)) || P <- Ps0]),
+    com_encoding(Ps).
+
+com_encoding(["latin","1"|_]) ->
+    latin1;
+com_encoding(["utf","8"|_]) ->
+    utf8;
+com_encoding(_) ->
+    throw(no). % Don't try any further
+
 normalize_typed_record_fields([]) ->
     {typed, []};
 normalize_typed_record_fields(Fields) ->
@@ -266,14 +438,17 @@ init_server(Pid, Name, File, AtLocation, Path, Pdm, Pre) ->
     Ms0 = predef_macros(Name),
     case user_predef(Pdm, Ms0) of
 	{ok,Ms1} ->
-	    epp_reply(Pid, {ok,self()}),
-            %% ensure directory of current source file is first in path
+            _ = set_encoding(File),
+            epp_reply(Pid, {ok,self()}),
+            %% ensure directory of current source file is
+            %% first in path
             Path1 = [filename:dirname(Name) | Path],
-	    St = #epp{file=File, location=AtLocation, delta=0, name=Name,
-                      name2=Name, path=Path1, macs=Ms1, pre_opened = Pre},
-	    From = wait_request(St),
-	    enter_file_reply(From, Name, AtLocation, AtLocation),
-	    wait_req_scan(St);
+            St = #epp{file=File, location=AtLocation, delta=0,
+                      name=Name, name2=Name, path=Path1, macs=Ms1,
+                      pre_opened = Pre},
+            From = wait_request(St),
+            enter_file_reply(From, Name, AtLocation, AtLocation),
+            wait_req_scan(St);
 	{error,E} ->
 	    epp_reply(Pid, {error,E})
     end.
@@ -385,19 +560,20 @@ enter_file(NewName, Inc, From, St) ->
 %% enter_file2(File, FullName, From, EppState, AtLocation) -> EppState.
 %%  Set epp to use this file and "enter" it.
 
-enter_file2(NewF, Pname, From, St, AtLocation) ->
+enter_file2(NewF, Pname, From, St0, AtLocation) ->
     Loc = start_loc(AtLocation),
     enter_file_reply(From, Pname, Loc, AtLocation),
-    Ms = dict:store({atom,'FILE'}, {none,[{string,Loc,Pname}]}, St#epp.macs),
+    Ms = dict:store({atom,'FILE'}, {none,[{string,Loc,Pname}]}, St0#epp.macs),
     %% update the head of the include path to be the directory of the new
     %% source file, so that an included file can always include other files
     %% relative to its current location (this is also how C does it); note
     %% that the directory of the parent source file (the previous head of
     %% the path) must be dropped, otherwise the path used within the current
     %% file will depend on the order of file inclusions in the parent files
-    Path = [filename:dirname(Pname) | tl(St#epp.path)],
+    Path = [filename:dirname(Pname) | tl(St0#epp.path)],
+    _ = set_encoding(NewF),
     #epp{file=NewF,location=Loc,name=Pname,delta=0,
-         sstk=[St|St#epp.sstk],path=Path,macs=Ms}.
+         sstk=[St0|St0#epp.sstk],path=Path,macs=Ms}.
 
 enter_file_reply(From, Name, Location, AtLocation) ->
     Attr = loc_attr(AtLocation),
@@ -456,7 +632,7 @@ leave_file(From, St) ->
 %% scan_toks(Tokens, From, EppState)
 
 scan_toks(From, St) ->
-    case io:scan_erl_form(St#epp.file, '', St#epp.location) of
+    case io:scan_erl_form(St#epp.file, '', St#epp.location, [unicode]) of
 	{ok,Toks,Cl} ->
 	    scan_toks(Toks, From, St#epp{location=Cl});
 	{error,E,Cl} ->
@@ -830,7 +1006,7 @@ new_location(Ln, {Le,_}, {Lf,_}) ->
 %%  nested conditionals and repeated 'else's.
 
 skip_toks(From, St, [I|Sis]) ->
-    case io:scan_erl_form(St#epp.file, '', St#epp.location) of
+    case io:scan_erl_form(St#epp.file, '', St#epp.location, [unicode]) of
 	{ok,[{'-',_Lh},{atom,_Li,ifdef}|_Toks],Cl} ->
 	    skip_toks(From, St#epp{location=Cl}, [ifdef,I|Sis]);
 	{ok,[{'-',_Lh},{atom,_Li,ifndef}|_Toks],Cl} ->
@@ -1094,6 +1270,7 @@ expand_arg([], Ts, L, Rest, Bs) ->
 %%% tokenized would yield the token list Ts.
 
 %% erl_scan:token_info(T, text) is not backward compatible with this.
+%% Note that escaped characters will be replaced by themselves.
 token_src({dot, _}) ->
     ".";
 token_src({X, _}) when is_atom(X) ->
@@ -1101,16 +1278,16 @@ token_src({X, _}) when is_atom(X) ->
 token_src({var, _, X}) ->
     atom_to_list(X);
 token_src({char,_,C}) ->
-    io_lib:write_char(C);
+    io_lib:write_unicode_char(C);
 token_src({string, _, X}) ->
-    lists:flatten(io_lib:format("~p", [X]));
+    io_lib:write_unicode_string(X);
 token_src({_, _, X}) ->
-    lists:flatten(io_lib:format("~w", [X])).
+    io_lib:format("~w", [X]).
 
 stringify1([]) ->
     [];
 stringify1([T | Tokens]) ->
-    [io_lib:format(" ~s", [token_src(T)]) | stringify1(Tokens)].
+    [io_lib:format(" ~ts", [token_src(T)]) | stringify1(Tokens)].
 
 stringify(Ts, L) ->
     [$\s | S] = lists:flatten(stringify1(Ts)),
diff --git a/lib/stdlib/src/erl_lint.erl b/lib/stdlib/src/erl_lint.erl
index 1e5f962375..0a442d950f 100644
--- a/lib/stdlib/src/erl_lint.erl
+++ b/lib/stdlib/src/erl_lint.erl
@@ -3618,6 +3618,10 @@ extract_sequence(4, [$t, $c | Fmt], Need) ->
     extract_sequence(5, [$c|Fmt], Need);
 extract_sequence(4, [$t, $s | Fmt], Need) ->
     extract_sequence(5, [$s|Fmt], Need);
+extract_sequence(4, [$t, $p | Fmt], Need) ->
+    extract_sequence(5, [$p|Fmt], Need);
+extract_sequence(4, [$t, $P | Fmt], Need) ->
+    extract_sequence(5, [$P|Fmt], Need);
 extract_sequence(4, [$t, C | _Fmt], _Need) ->
     {error,"invalid control ~t" ++ [C]};
 extract_sequence(4, Fmt, Need) ->
diff --git a/lib/stdlib/src/erl_parse.yrl b/lib/stdlib/src/erl_parse.yrl
index 928c10f7f2..27a2ba80eb 100644
--- a/lib/stdlib/src/erl_parse.yrl
+++ b/lib/stdlib/src/erl_parse.yrl
@@ -2,7 +2,7 @@
 %%
 %% %CopyrightBegin%
 %%
-%% Copyright Ericsson AB 1996-2011. All Rights Reserved.
+%% Copyright Ericsson AB 1996-2012. 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
@@ -923,73 +923,77 @@ normalise_list([]) ->
 -spec abstract(Data) -> AbsTerm when
       Data :: term(),
       AbsTerm :: abstract_expr().
-abstract(T) when is_integer(T) -> {integer,0,T};
-abstract(T) when is_float(T) -> {float,0,T};
-abstract(T) when is_atom(T) -> {atom,0,T};
-abstract([]) -> {nil,0};
-abstract(B) when is_bitstring(B) ->
-    {bin, 0, [abstract_byte(Byte, 0) || Byte <- bitstring_to_list(B)]};
-abstract([C|T]) when is_integer(C), 0 =< C, C < 256 ->
-    abstract_string(T, [C]);
-abstract([H|T]) ->
-    {cons,0,abstract(H),abstract(T)};
-abstract(Tuple) when is_tuple(Tuple) ->
-    {tuple,0,abstract_list(tuple_to_list(Tuple))}.
-
-abstract_string([C|T], String) when is_integer(C), 0 =< C, C < 256 ->
-    abstract_string(T, [C|String]);
-abstract_string([], String) ->
-    {string, 0, lists:reverse(String)};
-abstract_string(T, String) ->
-    not_string(String, abstract(T)).
-
-not_string([C|T], Result) ->
-    not_string(T, {cons, 0, {integer, 0, C}, Result});
-not_string([], Result) ->
+abstract(T) ->
+    abstract(T, 0, epp:default_encoding()).
+
+%%% abstract/2 takes line and encoding options
+-spec abstract(Data, Options) -> AbsTerm when
+      Data :: term(),
+      Options :: Line | [Option],
+      Option :: {line, Line} | {encoding, Encoding},
+      Encoding :: latin1 | unicode | utf8,
+      Line :: erl_scan:line(),
+      AbsTerm :: abstract_expr().
+
+abstract(T, Line) when is_integer(Line) ->
+    abstract(T, Line, epp:default_encoding());
+abstract(T, Options) when is_list(Options) ->
+    Line = proplists:get_value(line, Options, 0),
+    Encoding = proplists:get_value(encoding, Options,epp:default_encoding()),
+    abstract(T, Line, Encoding).
+
+-define(UNICODE(C),
+         (C >= 0 andalso C < 16#D800 orelse
+          C > 16#DFFF andalso C < 16#FFFE orelse
+          C > 16#FFFF andalso C =< 16#10FFFF)).
+
+abstract(T, L, _E) when is_integer(T) -> {integer,L,T};
+abstract(T, L, _E) when is_float(T) -> {float,L,T};
+abstract(T, L, _E) when is_atom(T) -> {atom,L,T};
+abstract([], L, _E) -> {nil,L};
+abstract(B, L, _E) when is_bitstring(B) ->
+    {bin, L, [abstract_byte(Byte, L) || Byte <- bitstring_to_list(B)]};
+abstract([C|T], L, unicode=E) when ?UNICODE(C) ->
+    abstract_unicode_string(T, [C], L, E);
+abstract([C|T], L, utf8=E) when ?UNICODE(C) ->
+    abstract_unicode_string(T, [C], L, E);
+abstract([C|T], L, latin1=E) when is_integer(C), 0 =< C, C < 256 ->
+    abstract_string(T, [C], L, E);
+abstract([H|T], L, E) ->
+    {cons,L,abstract(H, L, E),abstract(T, L, E)};
+abstract(Tuple, L, E) when is_tuple(Tuple) ->
+    {tuple,L,abstract_list(tuple_to_list(Tuple), L, E)}.
+
+abstract_string([C|T], String, L, E) when is_integer(C), 0 =< C, C < 256 ->
+    abstract_string(T, [C|String], L, E);
+abstract_string([], String, L, _E) ->
+    {string, L, lists:reverse(String)};
+abstract_string(T, String, L, E) ->
+    not_string(String, abstract(T, L, E), L, E).
+
+abstract_unicode_string([C|T], String, L, E) when ?UNICODE(C) ->
+    abstract_unicode_string(T, [C|String], L, E);
+abstract_unicode_string([], String, L, _E) ->
+    {string, L, lists:reverse(String)};
+abstract_unicode_string(T, String, L, E) ->
+    not_string(String, abstract(T, L, E), L, E).
+
+not_string([C|T], Result, L, E) ->
+    not_string(T, {cons, L, {integer, L, C}, Result}, L, E);
+not_string([], Result, _L, _E) ->
     Result.
 
-abstract_list([H|T]) ->
-    [abstract(H)|abstract_list(T)];
-abstract_list([]) ->
+abstract_list([H|T], L, E) ->
+    [abstract(H, L, E)|abstract_list(T, L, E)];
+abstract_list([], _L, _E) ->
     [].
 
-abstract_byte(Byte, Line) when is_integer(Byte) ->
-    {bin_element, Line, {integer, Line, Byte}, default, default};
-abstract_byte(Bits, Line) ->
+abstract_byte(Byte, L) when is_integer(Byte) ->
+    {bin_element, L, {integer, L, Byte}, default, default};
+abstract_byte(Bits, L) ->
     Sz = bit_size(Bits),
     <<Val:Sz>> = Bits,
-    {bin_element, Line, {integer, Line, Val}, {integer, Line, Sz}, default}.
-
-%%% abstract/2 keeps the line number
-abstract(T, Line) when is_integer(T) -> {integer,Line,T};
-abstract(T, Line) when is_float(T) -> {float,Line,T};
-abstract(T, Line) when is_atom(T) -> {atom,Line,T};
-abstract([], Line) -> {nil,Line};
-abstract(B, Line) when is_bitstring(B) ->
-    {bin, Line, [abstract_byte(Byte, Line) || Byte <- bitstring_to_list(B)]};
-abstract([C|T], Line) when is_integer(C), 0 =< C, C < 256 ->
-    abstract_string(T, [C], Line);
-abstract([H|T], Line) ->
-    {cons,Line,abstract(H, Line),abstract(T, Line)};
-abstract(Tuple, Line) when is_tuple(Tuple) ->
-    {tuple,Line,abstract_list(tuple_to_list(Tuple), Line)}.
-
-abstract_string([C|T], String, Line) when is_integer(C), 0 =< C, C < 256 ->
-    abstract_string(T, [C|String], Line);
-abstract_string([], String, Line) ->
-    {string, Line, lists:reverse(String)};
-abstract_string(T, String, Line) ->
-    not_string(String, abstract(T, Line), Line).
-
-not_string([C|T], Result, Line) ->
-    not_string(T, {cons, Line, {integer, Line, C}, Result}, Line);
-not_string([], Result, _Line) ->
-    Result.
-
-abstract_list([H|T], Line) ->
-    [abstract(H, Line)|abstract_list(T, Line)];
-abstract_list([], _Line) ->
-    [].
+    {bin_element, L, {integer, L, Val}, {integer, L, Sz}, default}.
 
 %%  Generate a list of tokens representing the abstract term.
 
diff --git a/lib/stdlib/src/erl_pp.erl b/lib/stdlib/src/erl_pp.erl
index 6b5aa951cf..0383ce6839 100644
--- a/lib/stdlib/src/erl_pp.erl
+++ b/lib/stdlib/src/erl_pp.erl
@@ -1,7 +1,7 @@
 %%
 %% %CopyrightBegin%
 %%
-%% Copyright Ericsson AB 1996-2011. All Rights Reserved.
+%% Copyright Ericsson AB 1996-2012. 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
@@ -26,7 +26,7 @@
          guard/1,guard/2,exprs/1,exprs/2,exprs/3,expr/1,expr/2,expr/3,expr/4]).
 
 -import(lists, [append/1,foldr/3,mapfoldl/3,reverse/1,reverse/2]).
--import(io_lib, [write/1,format/2,write_char/1,write_string/1]).
+-import(io_lib, [write/1,format/2]).
 -import(erl_parse, [inop_prec/1,preop_prec/1,func_prec/0,max_prec/0]).
 
 -define(MAXLINE, 72).
@@ -36,7 +36,15 @@
                               CurrentIndentation :: integer(),
                               CurrentPrecedence :: non_neg_integer(),
                               HookFunction :: hook_function()) ->
-                                    io_lib:chars())).
+                                   io_lib:chars())).
+
+-type(option() :: {hook, hook_function()}
+                | {encoding, latin1 | unicode | utf8}).
+-type(options() :: hook_function() | [option()]).
+
+-record(pp, {string_fun, char_fun}).
+
+-record(options, {hook, encoding, opts}).
 
 %%%
 %%% Exported functions
@@ -48,12 +56,12 @@
 form(Thing) ->
     form(Thing, none).
 
--spec(form(Form, HookFunction) -> io_lib:chars() when
+-spec(form(Form, Options) -> io_lib:chars() when
       Form :: erl_parse:abstract_form(),
-      HookFunction :: hook_function()).
+      Options :: options()).
 
-form(Thing, Hook) ->
-    frmt(lform(Thing, Hook)).
+form(Thing, Options) ->
+    frmt(lform(Thing, options(Options)), state(Options)).
 
 -spec(attribute(Attribute) -> io_lib:chars() when
       Attribute :: erl_parse:abstract_form()).
@@ -61,12 +69,12 @@ form(Thing, Hook) ->
 attribute(Thing) ->
     attribute(Thing, none).
 
--spec(attribute(Attribute, HookFunction) -> io_lib:chars() when
+-spec(attribute(Attribute, Options) -> io_lib:chars() when
       Attribute :: erl_parse:abstract_form(),
-      HookFunction :: hook_function()).
+      Options :: options()).
 
-attribute(Thing, Hook) ->
-    frmt(lattribute(Thing, Hook)).
+attribute(Thing, Options) ->
+    frmt(lattribute(Thing, options(Options)), state(Options)).
 
 -spec(function(Function) -> io_lib:chars() when
       Function :: erl_parse:abstract_form()).
@@ -74,18 +82,18 @@ attribute(Thing, Hook) ->
 function(F) ->
     function(F, none).
 
--spec(function(Function, HookFunction) -> io_lib:chars() when
+-spec(function(Function, Options) -> io_lib:chars() when
       Function :: erl_parse:abstract_form(),
-      HookFunction :: hook_function()).
+      Options :: options()).
 
-function(F, Hook) ->
-    frmt(lfunction(F, Hook)).
+function(F, Options) ->
+    frmt(lfunction(F, options(Options)), state(Options)).
 
 rule(R) ->
     rule(R, none).
 
-rule(R, Hook) ->
-    frmt(lrule(R, Hook)).
+rule(R, Options) ->
+    frmt(lrule(R, options(Options)), state(Options)).
 
 -spec(guard(Guard) -> io_lib:chars() when
       Guard :: [erl_parse:abstract_expr()]).
@@ -93,12 +101,12 @@ rule(R, Hook) ->
 guard(Gs) ->
     guard(Gs, none).
 
--spec(guard(Guard, HookFunction) -> io_lib:chars() when
+-spec(guard(Guard, Options) -> io_lib:chars() when
       Guard :: [erl_parse:abstract_expr()],
-      HookFunction :: hook_function()).
+      Options :: options()).
 
-guard(Gs, Hook) ->
-    frmt(lguard(Gs, Hook)).
+guard(Gs, Options) ->
+    frmt(lguard(Gs, options(Options)), state(Options)).
 
 -spec(exprs(Expressions) -> io_lib:chars() when
       Expressions :: [erl_parse:abstract_expr()]).
@@ -106,99 +114,129 @@ guard(Gs, Hook) ->
 exprs(Es) ->
     exprs(Es, 0, none).
 
--spec(exprs(Expressions, HookFunction) -> io_lib:chars() when
+-spec(exprs(Expressions, Options) -> io_lib:chars() when
       Expressions :: [erl_parse:abstract_expr()],
-      HookFunction :: hook_function()).
+      Options :: options()).
 
-exprs(Es, Hook) ->
-    exprs(Es, 0, Hook).
+exprs(Es, Options) ->
+    exprs(Es, 0, Options).
 
--spec(exprs(Expressions, Indent, HookFunction) -> io_lib:chars() when
+-spec(exprs(Expressions, Indent, Options) -> io_lib:chars() when
       Expressions :: [erl_parse:abstract_expr()],
       Indent :: integer(),
-      HookFunction :: hook_function()).
+      Options :: options()).
 
-exprs(Es, I, Hook) ->
-    frmt({seq,[],[],[$,],lexprs(Es, Hook)}, I).
+exprs(Es, I, Options) ->
+    frmt({seq,[],[],[$,],lexprs(Es, options(Options))}, I, state(Options)).
 
 -spec(expr(Expression) -> io_lib:chars() when
       Expression :: erl_parse:abstract_expr()).
 
 expr(E) ->
-    frmt(lexpr(E, 0, none)).
+    frmt(lexpr(E, 0, options(none)), state(none)).
 
--spec(expr(Expression, HookFunction) -> io_lib:chars() when
+-spec(expr(Expression, Options) -> io_lib:chars() when
       Expression :: erl_parse:abstract_expr(),
-      HookFunction :: hook_function()).
+      Options :: options()).
 
-expr(E, Hook) ->
-    frmt(lexpr(E, 0, Hook)).
+expr(E, Options) ->
+    frmt(lexpr(E, 0, options(Options)), state(Options)).
 
--spec(expr(Expression, Indent, HookFunction) -> io_lib:chars() when
+-spec(expr(Expression, Indent, Options) -> io_lib:chars() when
       Expression :: erl_parse:abstract_expr(),
       Indent :: integer(),
-      HookFunction :: hook_function()).
+      Options :: options()).
 
-expr(E, I, Hook) ->
-    frmt(lexpr(E, 0, Hook), I).
+expr(E, I, Options) ->
+    frmt(lexpr(E, 0, options(Options)), I, state(Options)).
 
--spec(expr(Expression, Indent, Precedence, HookFunction) -> io_lib:chars() when
+-spec(expr(Expression, Indent, Precedence, Options) -> io_lib:chars() when
       Expression :: erl_parse:abstract_expr(),
       Indent :: integer(),
       Precedence :: non_neg_integer(),
-      HookFunction :: hook_function()).
+      Options :: options()).
 
-expr(E, I, P, Hook) ->
-    frmt(lexpr(E, P, Hook), I).
+expr(E, I, P, Options) ->
+    frmt(lexpr(E, P, options(Options)), I, state(Options)).
 
 %%%
 %%% Local functions
 %%%
 
-lform({attribute,Line,Name,Arg}, Hook) ->
-    lattribute({attribute,Line,Name,Arg}, Hook);
-lform({function,Line,Name,Arity,Clauses}, Hook) ->
-    lfunction({function,Line,Name,Arity,Clauses}, Hook);
-lform({rule,Line,Name,Arity,Clauses}, Hook) ->
-    lrule({rule,Line,Name,Arity,Clauses}, Hook);
+options(Options) when is_list(Options) ->
+    Hook = proplists:get_value(hook, Options, none),
+    Encoding = encoding(Options),
+    #options{hook = Hook, encoding = Encoding, opts = Options};
+options(Hook) ->
+    #options{hook = Hook, encoding = encoding([]), opts = Hook}.
+
+state(Options) when is_list(Options) ->
+    case encoding(Options) of
+        latin1 -> state();
+        unicode -> unicode_state()
+    end;
+state(_Hook) ->
+    state().
+
+state() ->
+    #pp{string_fun = fun io_lib:write_unicode_string_as_latin1/1,
+        char_fun   = fun io_lib:write_unicode_char_as_latin1/1}.
+
+unicode_state() ->
+    #pp{string_fun = fun io_lib:write_unicode_string/1,
+        char_fun   = fun io_lib:write_unicode_char/1}.
+
+encoding(Options) ->
+    case proplists:get_value(encoding, Options, epp:default_encoding()) of
+        latin1 -> latin1;
+        utf8 -> unicode;
+        unicode -> unicode
+    end.
+
+lform({attribute,Line,Name,Arg}, Opts) ->
+    lattribute({attribute,Line,Name,Arg}, Opts);
+lform({function,Line,Name,Arity,Clauses}, Opts) ->
+    lfunction({function,Line,Name,Arity,Clauses}, Opts);
+lform({rule,Line,Name,Arity,Clauses}, Opts) ->
+    lrule({rule,Line,Name,Arity,Clauses}, Opts);
 %% These are specials to make it easier for the compiler.
-lform({error,E}, _Hook) ->
+lform({error,E}, _Opts) ->
     leaf(format("~p\n", [{error,E}]));
-lform({warning,W}, _Hook) ->
+lform({warning,W}, _Opts) ->
     leaf(format("~p\n", [{warning,W}]));
-lform({eof,_Line}, _Hook) ->
+lform({eof,_Line}, _Opts) ->
     $\n.
 
-lattribute({attribute,_Line,type,Type}, Hook) ->
-    [typeattr(type, Type, Hook),leaf(".\n")];
-lattribute({attribute,_Line,opaque,Type}, Hook) ->
-    [typeattr(opaque, Type, Hook),leaf(".\n")];
-lattribute({attribute,_Line,spec,Arg}, _Hook) ->
+lattribute({attribute,_Line,type,Type}, Opts) ->
+    [typeattr(type, Type, Opts),leaf(".\n")];
+lattribute({attribute,_Line,opaque,Type}, Opts) ->
+    [typeattr(opaque, Type, Opts),leaf(".\n")];
+lattribute({attribute,_Line,spec,Arg}, _Opts) ->
     [specattr(Arg),leaf(".\n")];
-lattribute({attribute,_Line,Name,Arg}, Hook) ->
-    [lattribute(Name, Arg, Hook),leaf(".\n")].
+lattribute({attribute,_Line,Name,Arg}, Opts) ->
+    [lattribute(Name, Arg, Opts),leaf(".\n")].
 
-lattribute(module, {M,Vs}, _Hook) ->
+lattribute(module, {M,Vs}, _Opts) ->
     attr("module",[{var,0,pname(M)},
                    foldr(fun(V, C) -> {cons,0,{var,0,V},C}
                          end, {nil,0}, Vs)]);
-lattribute(module, M, _Hook) ->
+lattribute(module, M, _Opts) ->
     attr("module", [{var,0,pname(M)}]);
-lattribute(export, Falist, _Hook) ->
+lattribute(export, Falist, _Opts) ->
     call({var,0,"-export"}, [falist(Falist)], 0, none);
-lattribute(import, Name, _Hook) when is_list(Name) ->
+lattribute(import, Name, _Opts) when is_list(Name) ->
     attr("import", [{var,0,pname(Name)}]);
-lattribute(import, {From,Falist}, _Hook) ->
+lattribute(import, {From,Falist}, _Opts) ->
     attr("import",[{var,0,pname(From)},falist(Falist)]);
-lattribute(file, {Name,Line}, _Hook) ->
+lattribute(file, {Name,Line}, _Opts) ->
     attr("file", [{var,0,format("~p", [Name])},{integer,0,Line}]);
-lattribute(record, {Name,Is}, Hook) ->
+lattribute(record, {Name,Is}, Opts) ->
     Nl = leaf(format("-record(~w,", [Name])),
-    [{first,Nl,record_fields(Is, Hook)},$)];
-lattribute(Name, Arg, _Hook) ->
-    attr(write(Name), [erl_parse:abstract(Arg)]).
+    [{first,Nl,record_fields(Is, Opts)},$)];
+lattribute(Name, Arg, #options{encoding = Encoding}) ->
+    attr(write(Name), [erl_parse:abstract(Arg, [{encoding,Encoding}])]).
 
-typeattr(Tag, {TypeName,Type,Args}, _Hook) ->
+typeattr(Tag, {TypeName,Type,Args}, _Opts) ->
     {first,leaf("-"++atom_to_list(Tag)++" "),
      typed(call({atom,0,TypeName}, Args, 0, none), Type)}.
 
@@ -293,7 +331,7 @@ guard_type(Before, Gs) ->
     Gl = {list,[{step,'when',expr_list(Gs, [$,], fun constraint/2, none)}]},
     {list,[{step,Before,Gl}]}.
 
-constraint({type,_Line,constraint,[Tag,As]}, _Hook) ->
+constraint({type,_Line,constraint,[Tag,As]}, _Opts) ->
     simple_type(Tag, As).
 
 fun_type(Before, {type,_,'fun',[FType,Ret]}) ->
@@ -333,231 +371,232 @@ falist([]) ->
 falist([{Name,Arity}|Falist]) ->
     {cons,0,{var,0,format("~w/~w", [Name,Arity])},falist(Falist)}.
 
-lfunction({function,_Line,Name,_Arity,Cs}, Hook) ->
-    Cll = nl_clauses(fun (C, H) -> func_clause(Name, C, H) end, $;, Hook, Cs),
+lfunction({function,_Line,Name,_Arity,Cs}, Opts) ->
+    Cll = nl_clauses(fun (C, H) -> func_clause(Name, C, H) end, $;, Opts, Cs),
     [Cll,leaf(".\n")].
 
-func_clause(Name, {clause,Line,Head,Guard,Body}, Hook) ->
-    Hl = call({atom,Line,Name}, Head, 0, Hook),
-    Gl = guard_when(Hl, Guard, Hook),
-    Bl = body(Body, Hook),
+func_clause(Name, {clause,Line,Head,Guard,Body}, Opts) ->
+    Hl = call({atom,Line,Name}, Head, 0, Opts),
+    Gl = guard_when(Hl, Guard, Opts),
+    Bl = body(Body, Opts),
     {step,Gl,Bl}.
 
-lrule({rule,_Line,Name,_Arity,Cs}, Hook) ->
-    Cll = nl_clauses(fun (C, H) -> rule_clause(Name, C, H) end, $;, Hook, Cs),
+lrule({rule,_Line,Name,_Arity,Cs}, Opts) ->
+    Cll = nl_clauses(fun (C, H) -> rule_clause(Name, C, H) end, $;, Opts, Cs),
     [Cll,leaf(".\n")].
 
-rule_clause(Name, {clause,Line,Head,Guard,Body}, Hook) ->
-    Hl = call({atom,Line,Name}, Head, 0, Hook),
-    Gl = guard_when(Hl, Guard, Hook, leaf(" :-")),
-    Bl = rule_body(Body, Hook),
+rule_clause(Name, {clause,Line,Head,Guard,Body}, Opts) ->
+    Hl = call({atom,Line,Name}, Head, 0, Opts),
+    Gl = guard_when(Hl, Guard, Opts, leaf(" :-")),
+    Bl = rule_body(Body, Opts),
     {step,Gl,Bl}.
 
-rule_body(Es, Hook) ->
-    lc_quals(Es, Hook).
+rule_body(Es, Opts) ->
+    lc_quals(Es, Opts).
 
-guard_when(Before, Guard, Hook) ->
-    guard_when(Before, Guard, Hook, ' ->').
+guard_when(Before, Guard, Opts) ->
+    guard_when(Before, Guard, Opts, ' ->').
 
-guard_when(Before, Guard, Hook, After) ->
-    Gl = lguard(Guard, Hook),
+guard_when(Before, Guard, Opts, After) ->
+    Gl = lguard(Guard, Opts),
     [{list,[{step,Before,Gl}]},After].
 
-lguard([E|Es], Hook) when is_list(E) ->
-    {list,[{step,'when',expr_list([E|Es], [$;], fun guard0/2, Hook)}]};
-lguard([E|Es], Hook) -> % before R6
-    lguard([[E|Es]], Hook);
+lguard([E|Es], Opts) when is_list(E) ->
+    {list,[{step,'when',expr_list([E|Es], [$;], fun guard0/2, Opts)}]};
+lguard([E|Es], Opts) -> % before R6
+    lguard([[E|Es]], Opts);
 lguard([], _) ->
     [].
 
-guard0(Es, Hook) ->
-    expr_list(Es, [$,], fun lexpr/2, Hook).
+guard0(Es, Opts) ->
+    expr_list(Es, [$,], fun lexpr/2, Opts).
 
-%% body(Before, Es, Hook) -> [Char].
+%% body(Before, Es, Opts) -> [Char].
 
-body([E], Hook) ->
-    lexpr(E, Hook);
-body(Es, Hook) ->
-    {prefer_nl,[$,],lexprs(Es, Hook)}.
+body([E], Opts) ->
+    lexpr(E, Opts);
+body(Es, Opts) ->
+    {prefer_nl,[$,],lexprs(Es, Opts)}.
 
-lexpr(E, Hook) ->
-    lexpr(E, 0, Hook).
+lexpr(E, Opts) ->
+    lexpr(E, 0, Opts).
 
 lexpr({var,_,V}, _, _) when is_integer(V) ->    %Special hack for Robert
     leaf(format("_~w", [V]));
 lexpr({var,_,V}, _, _) -> leaf(format("~s", [V]));
-lexpr({char,_,C}, _, _) -> leaf(write_char(C));
+lexpr({char,_,C}, _, _) -> {char,C};
 lexpr({integer,_,N}, _, _) -> leaf(write(N));
 lexpr({float,_,F}, _, _) -> leaf(write(F));
 lexpr({atom,_,A}, _, _) -> leaf(write(A));
 lexpr({string,_,S}, _, _) -> {string,S};
 lexpr({nil,_}, _, _) -> '[]';
-lexpr({cons,_,H,T}, _, Hook) ->
-    list(T, [H], Hook);
-lexpr({lc,_,E,Qs}, _Prec, Hook) ->
-    Lcl = {list,[{step,[lexpr(E, Hook),leaf(" ||")],lc_quals(Qs, Hook)}]},
+lexpr({cons,_,H,T}, _, Opts) ->
+    list(T, [H], Opts);
+lexpr({lc,_,E,Qs}, _Prec, Opts) ->
+    Lcl = {list,[{step,[lexpr(E, Opts),leaf(" ||")],lc_quals(Qs, Opts)}]},
     {list,[{seq,$[,[],[[]],[{force_nl,leaf(" "),[Lcl]}]},$]]};
     %% {list,[{step,$[,Lcl},$]]};
-lexpr({bc,_,E,Qs}, _Prec, Hook) ->
-    Lcl = {list,[{step,[lexpr(E, Hook),leaf(" ||")],lc_quals(Qs, Hook)}]},
+lexpr({bc,_,E,Qs}, _Prec, Opts) ->
+    Lcl = {list,[{step,[lexpr(E, Opts),leaf(" ||")],lc_quals(Qs, Opts)}]},
     {list,[{seq,'<<',[],[[]],[{force_nl,leaf(" "),[Lcl]}]},'>>']};
     %% {list,[{step,'<<',Lcl},'>>']};
-lexpr({tuple,_,Elts}, _, Hook) ->
-    tuple(Elts, Hook);
-%%lexpr({struct,_,Tag,Elts}, _, Hook) ->
-%%  {first,format("~w", [Tag]),tuple(Elts, Hook)};
-lexpr({record_index, _, Name, F}, Prec, Hook) ->
+lexpr({tuple,_,Elts}, _, Opts) ->
+    tuple(Elts, Opts);
+%%lexpr({struct,_,Tag,Elts}, _, Opts) ->
+%%  {first,format("~w", [Tag]),tuple(Elts, Opts)};
+lexpr({record_index, _, Name, F}, Prec, Opts) ->
     {P,R} = preop_prec('#'),
     Nl = record_name(Name),
-    El = [Nl,$.,lexpr(F, R, Hook)],
+    El = [Nl,$.,lexpr(F, R, Opts)],
     maybe_paren(P, Prec, El);
-lexpr({record, _, Name, Fs}, Prec, Hook) ->
+lexpr({record, _, Name, Fs}, Prec, Opts) ->
     {P,_R} = preop_prec('#'),
     Nl = record_name(Name),
-    El = {first,Nl,record_fields(Fs, Hook)},
+    El = {first,Nl,record_fields(Fs, Opts)},
     maybe_paren(P, Prec, El);
-lexpr({record_field, _, Rec, Name, F}, Prec, Hook) ->
+lexpr({record_field, _, Rec, Name, F}, Prec, Opts) ->
     {L,P,R} = inop_prec('#'),
-    Rl = lexpr(Rec, L, Hook),
+    Rl = lexpr(Rec, L, Opts),
     Nl = leaf(format("#~w.", [Name])),
-    El = [Rl,Nl,lexpr(F, R, Hook)],
+    El = [Rl,Nl,lexpr(F, R, Opts)],
     maybe_paren(P, Prec, El);
-lexpr({record, _, Rec, Name, Fs}, Prec, Hook) ->
+lexpr({record, _, Rec, Name, Fs}, Prec, Opts) ->
     {L,P,_R} = inop_prec('#'),
-    Rl = lexpr(Rec, L, Hook),
+    Rl = lexpr(Rec, L, Opts),
     Nl = record_name(Name),
-    El = {first,[Rl,Nl],record_fields(Fs, Hook)},
+    El = {first,[Rl,Nl],record_fields(Fs, Opts)},
     maybe_paren(P, Prec, El);
-lexpr({record_field, _, {atom,_,''}, F}, Prec, Hook) ->
+lexpr({record_field, _, {atom,_,''}, F}, Prec, Opts) ->
     {_L,P,R} = inop_prec('.'),
-    El = [$.,lexpr(F, R, Hook)],
+    El = [$.,lexpr(F, R, Opts)],
     maybe_paren(P, Prec, El);
-lexpr({record_field, _, Rec, F}, Prec, Hook) ->
+lexpr({record_field, _, Rec, F}, Prec, Opts) ->
     {L,P,R} = inop_prec('.'),
-    El = [lexpr(Rec, L, Hook),$.,lexpr(F, R, Hook)],
+    El = [lexpr(Rec, L, Opts),$.,lexpr(F, R, Opts)],
     maybe_paren(P, Prec, El);
-lexpr({block,_,Es}, _, Hook) ->
-    {list,[{step,'begin',body(Es, Hook)},'end']};
-lexpr({'if',_,Cs}, _, Hook) ->
-    {list,[{step,'if',if_clauses(Cs, Hook)},'end']};
-lexpr({'case',_,Expr,Cs}, _, Hook) ->
-    {list,[{step,{list,[{step,'case',lexpr(Expr, Hook)},'of']},
-            cr_clauses(Cs, Hook)},
+lexpr({block,_,Es}, _, Opts) ->
+    {list,[{step,'begin',body(Es, Opts)},'end']};
+lexpr({'if',_,Cs}, _, Opts) ->
+    {list,[{step,'if',if_clauses(Cs, Opts)},'end']};
+lexpr({'case',_,Expr,Cs}, _, Opts) ->
+    {list,[{step,{list,[{step,'case',lexpr(Expr, Opts)},'of']},
+            cr_clauses(Cs, Opts)},
            'end']};
-lexpr({'cond',_,Cs}, _, Hook) ->
-    {list,[{step,leaf("cond"),cond_clauses(Cs, Hook)},'end']};
-lexpr({'receive',_,Cs}, _, Hook) ->
-    {list,[{step,'receive',cr_clauses(Cs, Hook)},'end']};
-lexpr({'receive',_,Cs,To,ToOpt}, _, Hook) ->
-    Al = {list,[{step,[lexpr(To, Hook),' ->'],body(ToOpt, Hook)}]},
-    {list,[{step,'receive',cr_clauses(Cs, Hook)},
+lexpr({'cond',_,Cs}, _, Opts) ->
+    {list,[{step,leaf("cond"),cond_clauses(Cs, Opts)},'end']};
+lexpr({'receive',_,Cs}, _, Opts) ->
+    {list,[{step,'receive',cr_clauses(Cs, Opts)},'end']};
+lexpr({'receive',_,Cs,To,ToOpt}, _, Opts) ->
+    Al = {list,[{step,[lexpr(To, Opts),' ->'],body(ToOpt, Opts)}]},
+    {list,[{step,'receive',cr_clauses(Cs, Opts)},
            {step,'after',Al},
            'end']};
-lexpr({'fun',_,{function,F,A}}, _Prec, _Hook) ->
+lexpr({'fun',_,{function,F,A}}, _Prec, _Opts) ->
     leaf(format("fun ~w/~w", [F,A]));
-lexpr({'fun',_,{function,F,A},Extra}, _Prec, _Hook) ->
+lexpr({'fun',_,{function,F,A},Extra}, _Prec, _Opts) ->
     {force_nl,fun_info(Extra),leaf(format("fun ~w/~w", [F,A]))};
-lexpr({'fun',_,{function,M,F,A}}, _Prec, _Hook)
+lexpr({'fun',_,{function,M,F,A}}, _Prec, _Opts)
   when is_atom(M), is_atom(F), is_integer(A) ->
     %% For backward compatibility with pre-R15 abstract format.
     leaf(format("fun ~w:~w/~w", [M,F,A]));
-lexpr({'fun',_,{function,M,F,A}}, _Prec, Hook) ->
+lexpr({'fun',_,{function,M,F,A}}, _Prec, Opts) ->
     %% New format in R15.
-    NameItem = lexpr(M, Hook),
-    CallItem = lexpr(F, Hook),
-    ArityItem = lexpr(A, Hook),
+    NameItem = lexpr(M, Opts),
+    CallItem = lexpr(F, Opts),
+    ArityItem = lexpr(A, Opts),
     ["fun ",NameItem,$:,CallItem,$/,ArityItem];
-lexpr({'fun',_,{clauses,Cs}}, _Prec, Hook) ->
-    {list,[{first,'fun',fun_clauses(Cs, Hook)},'end']};
-lexpr({'fun',_,{clauses,Cs},Extra}, _Prec, Hook) ->
+lexpr({'fun',_,{clauses,Cs}}, _Prec, Opts) ->
+    {list,[{first,'fun',fun_clauses(Cs, Opts)},'end']};
+lexpr({'fun',_,{clauses,Cs},Extra}, _Prec, Opts) ->
     {force_nl,fun_info(Extra),
-     {list,[{first,'fun',fun_clauses(Cs, Hook)},'end']}};
-lexpr({'query',_,Lc}, _Prec, Hook) ->
-    {list,[{step,leaf("query"),lexpr(Lc, 0, Hook)},'end']};
-lexpr({call,_,{remote,_,{atom,_,M},{atom,_,F}=N}=Name,Args}, Prec, Hook) ->
+     {list,[{first,'fun',fun_clauses(Cs, Opts)},'end']}};
+lexpr({'query',_,Lc}, _Prec, Opts) ->
+    {list,[{step,leaf("query"),lexpr(Lc, 0, Opts)},'end']};
+lexpr({call,_,{remote,_,{atom,_,M},{atom,_,F}=N}=Name,Args}, Prec, Opts) ->
     case erl_internal:bif(M, F, length(Args)) of
         true ->
-            call(N, Args, Prec, Hook);
+            call(N, Args, Prec, Opts);
         false ->
-            call(Name, Args, Prec, Hook)
+            call(Name, Args, Prec, Opts)
     end;
-lexpr({call,_,Name,Args}, Prec, Hook) ->
-    call(Name, Args, Prec, Hook);
-lexpr({'try',_,Es,Scs,Ccs,As}, _, Hook) ->
+lexpr({call,_,Name,Args}, Prec, Opts) ->
+    call(Name, Args, Prec, Opts);
+lexpr({'try',_,Es,Scs,Ccs,As}, _, Opts) ->
     {list,[if
                Scs =:= [] ->
-                   {step,'try',body(Es, Hook)};
+                   {step,'try',body(Es, Opts)};
                true ->
-                   {step,{list,[{step,'try',body(Es, Hook)},'of']},
-                    cr_clauses(Scs, Hook)}
+                   {step,{list,[{step,'try',body(Es, Opts)},'of']},
+                    cr_clauses(Scs, Opts)}
            end,
            if
                Ccs =:= [] ->
                    [];
                true ->
-                   {step,'catch',try_clauses(Ccs, Hook)}
+                   {step,'catch',try_clauses(Ccs, Opts)}
            end,
            if
                As =:= [] ->
                    [];
                true ->
-                   {step,'after',body(As, Hook)}
+                   {step,'after',body(As, Opts)}
            end,
            'end']};
-lexpr({'catch',_,Expr}, Prec, Hook) ->
+lexpr({'catch',_,Expr}, Prec, Opts) ->
     {P,R} = preop_prec('catch'),
-    El = {list,[{step,'catch',lexpr(Expr, R, Hook)}]},
+    El = {list,[{step,'catch',lexpr(Expr, R, Opts)}]},
     maybe_paren(P, Prec, El);
-lexpr({match,_,Lhs,Rhs}, Prec, Hook) ->
+lexpr({match,_,Lhs,Rhs}, Prec, Opts) ->
     {L,P,R} = inop_prec('='),
-    Pl = lexpr(Lhs, L, Hook),
-    Rl = lexpr(Rhs, R, Hook),
+    Pl = lexpr(Lhs, L, Opts),
+    Rl = lexpr(Rhs, R, Opts),
     El = {list,[{cstep,[Pl,' ='],Rl}]},
     maybe_paren(P, Prec, El);
-lexpr({op,_,Op,Arg}, Prec, Hook) ->
+lexpr({op,_,Op,Arg}, Prec, Opts) ->
     {P,R} = preop_prec(Op),
     Ol = leaf(format("~s ", [Op])),
-    El = [Ol,lexpr(Arg, R, Hook)],
+    El = [Ol,lexpr(Arg, R, Opts)],
     maybe_paren(P, Prec, El);
-lexpr({op,_,Op,Larg,Rarg}, Prec, Hook)  when Op =:= 'orelse';
+lexpr({op,_,Op,Larg,Rarg}, Prec, Opts)  when Op =:= 'orelse';
                                              Op =:= 'andalso' ->
     %% Breaks lines since R12B.
     {L,P,R} = inop_prec(Op),
-    Ll = lexpr(Larg, L, Hook),
+    Ll = lexpr(Larg, L, Opts),
     Ol = leaf(format("~s", [Op])),
-    Lr = lexpr(Rarg, R, Hook),
+    Lr = lexpr(Rarg, R, Opts),
     El = {prefer_nl,[[]],[Ll,Ol,Lr]},
     maybe_paren(P, Prec, El);
-lexpr({op,_,Op,Larg,Rarg}, Prec, Hook) ->
+lexpr({op,_,Op,Larg,Rarg}, Prec, Opts) ->
     {L,P,R} = inop_prec(Op),
-    Ll = lexpr(Larg, L, Hook),
+    Ll = lexpr(Larg, L, Opts),
     Ol = leaf(format("~s", [Op])),
-    Lr = lexpr(Rarg, R, Hook),
+    Lr = lexpr(Rarg, R, Opts),
     El = {list,[Ll,Ol,Lr]},
     maybe_paren(P, Prec, El);
 %% Special expressions which are not really legal everywhere.
-lexpr({remote,_,M,F}, Prec, Hook) ->
+lexpr({remote,_,M,F}, Prec, Opts) ->
     {L,P,R} = inop_prec(':'),
-    NameItem = lexpr(M, L, Hook),
-    CallItem = lexpr(F, R, Hook),
+    NameItem = lexpr(M, L, Opts),
+    CallItem = lexpr(F, R, Opts),
     maybe_paren(P, Prec, [NameItem,$:,CallItem]);
 %% BIT SYNTAX:
-lexpr({bin,_,Fs}, _, Hook) ->
-    bit_grp(Fs, Hook);
+lexpr({bin,_,Fs}, _, Opts) ->
+    bit_grp(Fs, Opts);
 %% Special case for straight values.
 lexpr({value,_,Val}, _,_) ->
     leaf(write(Val));
 %% Now do the hook.
-lexpr(Other, _Precedence, none) ->
+lexpr(Other, _Precedence, #options{hook = none}) ->
     leaf(format("INVALID-FORM:~w:",[Other]));
-lexpr(HookExpr, Precedence, {Mod,Func,Eas}) when Mod =/= 'fun' ->
+lexpr(HookExpr, Precedence, #options{hook = {Mod,Func,Eas}})
+                                        when Mod =/= 'fun' ->
     {ehook,HookExpr,Precedence,{Mod,Func,Eas}};
-lexpr(HookExpr, Precedence, Func) ->
-    {hook,HookExpr,Precedence,Func}.
+lexpr(HookExpr, Precedence, #options{hook = Func, opts = Options}) ->
+    {hook,HookExpr,Precedence,Func,Options}.
 
-call(Name, Args, Prec, Hook) ->
+call(Name, Args, Prec, Opts) ->
     {F,P} = func_prec(),
-    Item = {first,lexpr(Name, F, Hook),args(Args, Hook)},
+    Item = {first,lexpr(Name, F, Opts),args(Args, Opts)},
     maybe_paren(P, Prec, Item).
 
 fun_info(Extra) ->
@@ -565,32 +604,18 @@ fun_info(Extra) ->
 
 %% BITS:
 
-bit_grp(Fs, Hook) ->
-    append([['<<'],
-            [try
-                 true = Fs =/= [],
-                 S = bin_string(Fs),
-                 true = io_lib:printable_list(S),
-                 {string,S}
-             catch _:_ ->
-                 bit_elems(Fs, Hook)
-             end],
-            ['>>']]).
-
-bin_string([]) ->
-    [];
-bin_string([{bin_element,_,{char,_,C},_,_}|Bin]) ->
-    [C | bin_string(Bin)].
+bit_grp(Fs, Opts) ->
+    append([['<<'], [bit_elems(Fs, Opts)], ['>>']]).
 
-bit_elems(Es, Hook) ->
-    expr_list(Es, $,, fun bit_elem/2, Hook).
+bit_elems(Es, Opts) ->
+    expr_list(Es, $,, fun bit_elem/2, Opts).
 
-bit_elem({bin_element,_,Expr,Sz,Types}, Hook) ->
+bit_elem({bin_element,_,Expr,Sz,Types}, Opts) ->
     P = max_prec(),
-    VChars = lexpr(Expr, P, Hook),
+    VChars = lexpr(Expr, P, Opts),
     SChars = if
                  Sz =/= default ->
-                     [VChars,$:,lexpr(Sz, P, Hook)];
+                     [VChars,$:,lexpr(Sz, P, Opts)];
                  true ->
                      VChars
              end,
@@ -618,157 +643,157 @@ bit_elem_type(T) ->
 record_name(Name) ->
     leaf(format("#~w", [Name])).
 
-record_fields(Fs, Hook) ->
-    tuple(Fs, fun record_field/2, Hook).
+record_fields(Fs, Opts) ->
+    tuple(Fs, fun record_field/2, Opts).
 
-record_field({record_field,_,F,Val}, Hook) ->
+record_field({record_field,_,F,Val}, Opts) ->
     {L,_P,R} = inop_prec('='),
-    Fl = lexpr(F, L, Hook),
-    Vl = lexpr(Val, R, Hook),
+    Fl = lexpr(F, L, Opts),
+    Vl = lexpr(Val, R, Opts),
     {list,[{cstep,[Fl,' ='],Vl}]};
-record_field({typed_record_field,{record_field,_,F,Val},Type}, Hook) ->
+record_field({typed_record_field,{record_field,_,F,Val},Type}, Opts) ->
     {L,_P,R} = inop_prec('='),
-    Fl = lexpr(F, L, Hook),
-    Vl = typed(lexpr(Val, R, Hook), Type),
+    Fl = lexpr(F, L, Opts),
+    Vl = typed(lexpr(Val, R, Opts), Type),
     {list,[{cstep,[Fl,' ='],Vl}]};
-record_field({typed_record_field,Field,Type}, Hook) ->
-    typed(record_field(Field, Hook), Type);
-record_field({record_field,_,F}, Hook) ->
-    lexpr(F, 0, Hook).
-
-list({cons,_,H,T}, Es, Hook) ->
-    list(T, [H|Es], Hook);
-list({nil,_}, Es, Hook) ->
-    proper_list(reverse(Es), Hook);
-list(Other, Es, Hook) ->
-    improper_list(reverse(Es, [Other]), Hook).
-
-%% if_clauses(Clauses, Hook) -> [Char].
+record_field({typed_record_field,Field,Type}, Opts) ->
+    typed(record_field(Field, Opts), Type);
+record_field({record_field,_,F}, Opts) ->
+    lexpr(F, 0, Opts).
+
+list({cons,_,H,T}, Es, Opts) ->
+    list(T, [H|Es], Opts);
+list({nil,_}, Es, Opts) ->
+    proper_list(reverse(Es), Opts);
+list(Other, Es, Opts) ->
+    improper_list(reverse(Es, [Other]), Opts).
+
+%% if_clauses(Clauses, Opts) -> [Char].
 %%  Print 'if' clauses.
 
-if_clauses(Cs, Hook) ->
-    clauses(fun if_clause/2, Hook, Cs).
+if_clauses(Cs, Opts) ->
+    clauses(fun if_clause/2, Opts, Cs).
 
-if_clause({clause,_,[],G,B}, Hook) ->
-    Gl = [guard_no_when(G, Hook),' ->'],
-    {step,Gl,body(B, Hook)}.
+if_clause({clause,_,[],G,B}, Opts) ->
+    Gl = [guard_no_when(G, Opts),' ->'],
+    {step,Gl,body(B, Opts)}.
 
-guard_no_when([E|Es], Hook) when is_list(E) ->
-    expr_list([E|Es], $;, fun guard0/2, Hook);
-guard_no_when([E|Es], Hook) -> % before R6
-    guard_no_when([[E|Es]], Hook);
+guard_no_when([E|Es], Opts) when is_list(E) ->
+    expr_list([E|Es], $;, fun guard0/2, Opts);
+guard_no_when([E|Es], Opts) -> % before R6
+    guard_no_when([[E|Es]], Opts);
 guard_no_when([], _) -> % cannot happen
     leaf("true").
 
-%% cr_clauses(Clauses, Hook) -> [Char].
+%% cr_clauses(Clauses, Opts) -> [Char].
 %%  Print 'case'/'receive' clauses.
 
-cr_clauses(Cs, Hook) ->
-    clauses(fun cr_clause/2, Hook, Cs).
+cr_clauses(Cs, Opts) ->
+    clauses(fun cr_clause/2, Opts, Cs).
 
-cr_clause({clause,_,[T],G,B}, Hook) ->
-    El = lexpr(T, 0, Hook),
-    Gl = guard_when(El, G, Hook),
-    Bl = body(B, Hook),
+cr_clause({clause,_,[T],G,B}, Opts) ->
+    El = lexpr(T, 0, Opts),
+    Gl = guard_when(El, G, Opts),
+    Bl = body(B, Opts),
     {step,Gl,Bl}.
 
-%% try_clauses(Clauses, Hook) -> [Char].
+%% try_clauses(Clauses, Opts) -> [Char].
 %%  Print 'try' clauses.
 
-try_clauses(Cs, Hook) ->
-    clauses(fun try_clause/2, Hook, Cs).
+try_clauses(Cs, Opts) ->
+    clauses(fun try_clause/2, Opts, Cs).
 
-try_clause({clause,_,[{tuple,_,[{atom,_,throw},V,S]}],G,B}, Hook) ->
-    El = lexpr(V, 0, Hook),
-    Sl = stack_backtrace(S, [El], Hook),
-    Gl = guard_when(Sl, G, Hook),
-    Bl = body(B, Hook),
+try_clause({clause,_,[{tuple,_,[{atom,_,throw},V,S]}],G,B}, Opts) ->
+    El = lexpr(V, 0, Opts),
+    Sl = stack_backtrace(S, [El], Opts),
+    Gl = guard_when(Sl, G, Opts),
+    Bl = body(B, Opts),
     {step,Gl,Bl};
-try_clause({clause,_,[{tuple,_,[C,V,S]}],G,B}, Hook) ->
-    Cs = lexpr(C, 0, Hook),
-    El = lexpr(V, 0, Hook),
+try_clause({clause,_,[{tuple,_,[C,V,S]}],G,B}, Opts) ->
+    Cs = lexpr(C, 0, Opts),
+    El = lexpr(V, 0, Opts),
     CsEl = [Cs,$:,El],
-    Sl = stack_backtrace(S, CsEl, Hook),
-    Gl = guard_when(Sl, G, Hook),
-    Bl = body(B, Hook),
+    Sl = stack_backtrace(S, CsEl, Opts),
+    Gl = guard_when(Sl, G, Opts),
+    Bl = body(B, Opts),
     {step,Gl,Bl}.
 
-stack_backtrace({var,_,'_'}, El, _Hook) ->
+stack_backtrace({var,_,'_'}, El, _Opts) ->
     El;
-stack_backtrace(S, El, Hook) ->
-    El++[$:,lexpr(S, 0, Hook)].
+stack_backtrace(S, El, Opts) ->
+    El++[$:,lexpr(S, 0, Opts)].
 
-%% fun_clauses(Clauses, Hook) -> [Char].
+%% fun_clauses(Clauses, Opts) -> [Char].
 %%  Print 'fun' clauses.
 
-fun_clauses(Cs, Hook) ->
-    nl_clauses(fun fun_clause/2, [$;], Hook, Cs).
+fun_clauses(Cs, Opts) ->
+    nl_clauses(fun fun_clause/2, [$;], Opts, Cs).
 
-fun_clause({clause,_,A,G,B}, Hook) ->
-    El = args(A, Hook),
-    Gl = guard_when(El, G, Hook),
-    Bl = body(B, Hook),
+fun_clause({clause,_,A,G,B}, Opts) ->
+    El = args(A, Opts),
+    Gl = guard_when(El, G, Opts),
+    Bl = body(B, Opts),
     {step,Gl,Bl}.
 
-%% cond_clauses(Clauses, Hook) -> [Char].
+%% cond_clauses(Clauses, Opts) -> [Char].
 %%  Print 'cond' clauses.
 
-cond_clauses(Cs, Hook) ->
-    clauses(fun cond_clause/2, Hook, Cs).
+cond_clauses(Cs, Opts) ->
+    clauses(fun cond_clause/2, Opts, Cs).
 
-cond_clause({clause,_,[],[[E]],B}, Hook) ->
-    {step,[lexpr(E, Hook),' ->'],body(B, Hook)}.
+cond_clause({clause,_,[],[[E]],B}, Opts) ->
+    {step,[lexpr(E, Opts),' ->'],body(B, Opts)}.
 
-%% nl_clauses(Type, Hook, Clauses) -> [Char].
+%% nl_clauses(Type, Opts, Clauses) -> [Char].
 %%  Generic clause printing function (always breaks lines).
 
-nl_clauses(Type, Sep, Hook, Cs) ->
-    {prefer_nl,Sep,lexprs(Cs, Type, Hook)}.
+nl_clauses(Type, Sep, Opts, Cs) ->
+    {prefer_nl,Sep,lexprs(Cs, Type, Opts)}.
 
-%% clauses(Type, Hook, Clauses) -> [Char].
+%% clauses(Type, Opts, Clauses) -> [Char].
 %%  Generic clause printing function (breaks lines since R12B).
 
-clauses(Type, Hook, Cs) ->
-    {prefer_nl,[$;],lexprs(Cs, Type, Hook)}.
+clauses(Type, Opts, Cs) ->
+    {prefer_nl,[$;],lexprs(Cs, Type, Opts)}.
 
-%% lc_quals(Qualifiers, After, Hook)
+%% lc_quals(Qualifiers, After, Opts)
 %% List comprehension qualifiers (breaks lines since R12B).
 
-lc_quals(Qs, Hook) ->
-    {prefer_nl,[$,],lexprs(Qs, fun lc_qual/2, Hook)}.
+lc_quals(Qs, Opts) ->
+    {prefer_nl,[$,],lexprs(Qs, fun lc_qual/2, Opts)}.
 
-lc_qual({b_generate,_,Pat,E}, Hook) ->
-    Pl = lexpr(Pat, 0, Hook),
-    {list,[{step,[Pl,leaf(" <=")],lexpr(E, 0, Hook)}]};
-lc_qual({generate,_,Pat,E}, Hook) ->
-    Pl = lexpr(Pat, 0, Hook),
-    {list,[{step,[Pl,leaf(" <-")],lexpr(E, 0, Hook)}]};
-lc_qual(Q, Hook) ->
-    lexpr(Q, 0, Hook).
+lc_qual({b_generate,_,Pat,E}, Opts) ->
+    Pl = lexpr(Pat, 0, Opts),
+    {list,[{step,[Pl,leaf(" <=")],lexpr(E, 0, Opts)}]};
+lc_qual({generate,_,Pat,E}, Opts) ->
+    Pl = lexpr(Pat, 0, Opts),
+    {list,[{step,[Pl,leaf(" <-")],lexpr(E, 0, Opts)}]};
+lc_qual(Q, Opts) ->
+    lexpr(Q, 0, Opts).
 
-proper_list(Es, Hook) ->
-    {seq,$[,$],$,,lexprs(Es, Hook)}.
+proper_list(Es, Opts) ->
+    {seq,$[,$],$,,lexprs(Es, Opts)}.
 
-improper_list(Es, Hook) ->
-    {seq,$[,$],{$,,$|},lexprs(Es, Hook)}.
+improper_list(Es, Opts) ->
+    {seq,$[,$],{$,,$|},lexprs(Es, Opts)}.
 
-tuple(L, Hook) ->
-    tuple(L, fun lexpr/2, Hook).
+tuple(L, Opts) ->
+    tuple(L, fun lexpr/2, Opts).
 
-tuple(Es, F, Hook) ->
-    {seq,${,$},$,,lexprs(Es, F, Hook)}.
+tuple(Es, F, Opts) ->
+    {seq,${,$},$,,lexprs(Es, F, Opts)}.
 
-args(As, Hook) ->
-    {seq,$(,$),[$,],lexprs(As, Hook)}.
+args(As, Opts) ->
+    {seq,$(,$),[$,],lexprs(As, Opts)}.
 
-expr_list(Es, Sep, F, Hook) ->
-    {seq,[],[],Sep,lexprs(Es, F, Hook)}.
+expr_list(Es, Sep, F, Opts) ->
+    {seq,[],[],Sep,lexprs(Es, F, Opts)}.
 
-lexprs(Es, Hook) ->
-    lexprs(Es, fun lexpr/2, Hook).
+lexprs(Es, Opts) ->
+    lexprs(Es, fun lexpr/2, Opts).
 
-lexprs(Es, F, Hook) ->
-    [F(E, Hook) || E <- Es].
+lexprs(Es, F, Opts) ->
+    [F(E, Opts) || E <- Es].
 
 maybe_paren(P, Prec, Expr) when P < Prec ->
     [$(,Expr,$)];
@@ -781,13 +806,13 @@ leaf(S) ->
 %%% Do the formatting. Currently nothing fancy. Could probably have
 %%% done it in one single pass.
 
-frmt(Item) ->
-    frmt(Item, 0).
+frmt(Item, PP) ->
+    frmt(Item, 0, PP).
 
-frmt(Item, I) ->
+frmt(Item, I, PP) ->
     ST = spacetab(),
     WT = wordtable(),
-    {Chars,_Length} = f(Item, I, ST, WT),
+    {Chars,_Length} = f(Item, I, ST, WT, PP),
     [Chars].
 
 %%% What the tags mean:
@@ -803,6 +828,7 @@ frmt(Item, I) ->
 %%% - {force_nl,ExtraInfo,I}: fun-info (a comment) forces linebreak before I.
 %%% - {prefer_nl,Sep,IPs}: forces linebreak between Is unlesss negative
 %%%   indentation.
+%%% - {char,C}: a character
 %%% - {string,S}: a string.
 %%% - {hook,...}, {ehook,...}: hook expressions.
 %%%
@@ -812,22 +838,22 @@ frmt(Item, I) ->
 %%% cstep works similarly, but no linebreak if the width of I1 is less
 %%% than the indentation (this is for "A = <expression over several lines>).
 
-f([]=Nil, _I0, _ST, _WT) ->
+f([]=Nil, _I0, _ST, _WT, _PP) ->
     {Nil,0};
-f(C, _I0, _ST, _WT) when is_integer(C) ->
+f(C, _I0, _ST, _WT, _PP) when is_integer(C) ->
     {C,1};
-f({leaf,Length,Chars}, _I0, _ST, _WT) ->
+f({leaf,Length,Chars}, _I0, _ST, _WT, _PP) ->
     {Chars,Length};
-f([Item|Items], I0, ST, WT) ->
-    consecutive(Items, f(Item, I0, ST, WT), I0, ST, WT);
-f({list,Items}, I0, ST, WT) ->
-    f({seq,[],[],[[]],Items}, I0, ST, WT);
-f({first,E,Item}, I0, ST, WT) ->
-    f({seq,E,[],[[]],[Item]}, I0, ST, WT);
-f({seq,Before,After,Sep,LItems}, I0, ST, WT) ->
-    BCharsSize = f(Before, I0, ST, WT),
+f([Item|Items], I0, ST, WT, PP) ->
+    consecutive(Items, f(Item, I0, ST, WT, PP), I0, ST, WT, PP);
+f({list,Items}, I0, ST, WT, PP) ->
+    f({seq,[],[],[[]],Items}, I0, ST, WT, PP);
+f({first,E,Item}, I0, ST, WT, PP) ->
+    f({seq,E,[],[[]],[Item]}, I0, ST, WT, PP);
+f({seq,Before,After,Sep,LItems}, I0, ST, WT, PP) ->
+    BCharsSize = f(Before, I0, ST, WT, PP),
     I = indent(BCharsSize, I0),
-    CharsSizeL = fl(LItems, Sep, I, After, ST, WT),
+    CharsSizeL = fl(LItems, Sep, I, After, ST, WT, PP),
     {CharsL,SizeL} = unz(CharsSizeL),
     {BCharsL,BSizeL} = unz1([BCharsSize]),
     Sizes = BSizeL ++ SizeL,
@@ -848,15 +874,15 @@ f({seq,Before,After,Sep,LItems}, I0, ST, WT) ->
             {BCharsL++insert_newlines(CharsSizeL, I, ST),
              nsz(lists:last(Sizes), I0)}
     end;
-f({force_nl,_ExtraInfoItem,Item}, I, ST, WT) when I < 0 ->
+f({force_nl,_ExtraInfoItem,Item}, I, ST, WT, PP) when I < 0 ->
     %% Extra info is a comment; cannot have that on the same line
-    f(Item, I, ST, WT);
-f({force_nl,ExtraInfoItem,Item}, I, ST, WT) ->
-    f({prefer_nl,[],[ExtraInfoItem,Item]}, I, ST, WT);
-f({prefer_nl,Sep,LItems}, I, ST, WT) when I < 0 ->
-    f({seq,[],[],Sep,LItems}, I, ST, WT);
-f({prefer_nl,Sep,LItems}, I0, ST, WT) ->
-    CharsSize2L = fl(LItems, Sep, I0, [], ST, WT),
+    f(Item, I, ST, WT, PP);
+f({force_nl,ExtraInfoItem,Item}, I, ST, WT, PP) ->
+    f({prefer_nl,[],[ExtraInfoItem,Item]}, I, ST, WT, PP);
+f({prefer_nl,Sep,LItems}, I, ST, WT, PP) when I < 0 ->
+    f({seq,[],[],Sep,LItems}, I, ST, WT, PP);
+f({prefer_nl,Sep,LItems}, I0, ST, WT, PP) ->
+    CharsSize2L = fl(LItems, Sep, I0, [], ST, WT, PP),
     {_CharsL,Sizes} = unz(CharsSize2L),
     if
         Sizes =:= [] ->
@@ -864,37 +890,40 @@ f({prefer_nl,Sep,LItems}, I0, ST, WT) ->
         true ->
             {insert_newlines(CharsSize2L, I0, ST),nsz(lists:last(Sizes), I0)}
     end;
-f({string,S}, I, ST, WT) ->
-    f(write_a_string(S, I), I, ST, WT);
-f({hook,HookExpr,Precedence,Func}, I, _ST, _WT) ->
-    Chars = Func(HookExpr, I, Precedence, Func),
+f({char,C}, I, ST, WT, PP) ->
+    f(write_a_char(C, PP), I, ST, WT, PP);
+f({string,S}, I, ST, WT, PP) ->
+    f(write_a_string(S, I, PP), I, ST, WT, PP);
+f({hook,HookExpr,Precedence,Func,Options}, I, _ST, _WT, _PP) ->
+    Chars = Func(HookExpr, I, Precedence, Options),
     {Chars,indentation(Chars, I)};
-f({ehook,HookExpr,Precedence,{Mod,Func,Eas}=ModFuncEas}, I, _ST, _WT) ->
+f({ehook,HookExpr,Precedence,{Mod,Func,Eas}=ModFuncEas}, I, _ST, _WT, _PP) ->
     Chars = apply(Mod, Func, [HookExpr,I,Precedence,ModFuncEas|Eas]),
     {Chars,indentation(Chars, I)};
-f(WordName, _I, _ST, WT) -> % when is_atom(WordName)
+f(WordName, _I, _ST, WT, _PP) -> % when is_atom(WordName)
     word(WordName, WT).
 
 -define(IND, 4).
 
 %% fl(ListItems, I0, ST, WT) -> [[CharsSize1,CharsSize2]]
 %% ListItems = [{Item,Items}|Item]
-fl([], _Sep, I0, After, ST, WT) ->
-    [[f(After, I0, ST, WT),{[],0}]];
-fl(CItems, Sep0, I0, After, ST, WT) ->
+fl([], _Sep, I0, After, ST, WT, PP) ->
+    [[f(After, I0, ST, WT, PP),{[],0}]];
+fl(CItems, Sep0, I0, After, ST, WT, PP) ->
     F = fun({step,Item1,Item2}, S) ->
-                [f(Item1, I0, ST, WT),f([Item2,S], incr(I0, ?IND), ST, WT)];
+                [f(Item1, I0, ST, WT, PP),
+                 f([Item2,S], incr(I0, ?IND), ST, WT, PP)];
            ({cstep,Item1,Item2}, S) ->
-                {_,Sz1} = CharSize1 = f(Item1, I0, ST, WT),
+                {_,Sz1} = CharSize1 = f(Item1, I0, ST, WT, PP),
                 if
                     is_integer(Sz1), Sz1 < ?IND ->
                         Item2p = [leaf("\s"),Item2,S],
-                        [consecutive(Item2p, CharSize1, I0, ST, WT),{[],0}];
+                        [consecutive(Item2p, CharSize1, I0, ST, WT, PP),{[],0}];
                     true ->
-                        [CharSize1,f([Item2,S], incr(I0, ?IND), ST, WT)]
+                        [CharSize1,f([Item2,S], incr(I0, ?IND), ST, WT, PP)]
                 end;
            (Item, S) ->
-                [f([Item,S], I0, ST, WT),{[],0}]
+                [f([Item,S], I0, ST, WT, PP),{[],0}]
         end,
     {Sep,LastSep}  = case Sep0 of {_,_} -> Sep0; _ -> {Sep0,Sep0} end,
     fl1(CItems, F, Sep, LastSep, After).
@@ -906,10 +935,10 @@ fl1([CItem1,CItem2], F, _Sep, LastSep, After) ->
 fl1([CItem|CItems], F, Sep, LastSep, After) ->
     [F(CItem, Sep)|fl1(CItems, F, Sep, LastSep, After)].
 
-consecutive(Items, CharSize1, I0, ST, WT) ->
+consecutive(Items, CharSize1, I0, ST, WT, PP) ->
     {CharsSizes,_Length} =
         mapfoldl(fun(Item, Len) ->
-                         CharsSize = f(Item, Len, ST, WT),
+                         CharsSize = f(Item, Len, ST, WT, PP),
                          {CharsSize,indent(CharsSize, Len)}
                  end, indent(CharSize1, I0), Items),
     {CharsL,SizeL} = unz1([CharSize1|CharsSizes]),
@@ -999,26 +1028,40 @@ has_nl([C|Cs]) ->
 has_nl([]) ->
     false.
 
+write_a_char(C, PP) ->
+    flat_leaf(write_char(C, PP)).
+
 -define(MIN_SUBSTRING, 5).
 
-write_a_string(S, I) when I < 0; S =:= [] ->
-    leaf(write_string(S));
-write_a_string(S, I) ->
+write_a_string(S, I, PP) when I < 0; S =:= [] ->
+    flat_leaf(write_string(S, PP));
+write_a_string(S, I, PP) ->
     Len = erlang:max(?MAXLINE-I, ?MIN_SUBSTRING),
-    {list,write_a_string(S, Len, Len)}.
+    {list,write_a_string(S, Len, Len, PP)}.
 
-write_a_string([], _N, _Len) ->
+write_a_string([], _N, _Len, _PP) ->
     [];
-write_a_string(S, N, Len) ->
+write_a_string(S, N, Len, PP) ->
     SS = string:sub_string(S, 1, N),
-    Sl = write_string(SS),
-    case (iolist_size(Sl) > Len) and (N > ?MIN_SUBSTRING) of
+    Sl = write_string(SS, PP),
+    case (length(Sl) > Len) and (N > ?MIN_SUBSTRING) of
         true ->
-            write_a_string(S, N-1, Len);
+            write_a_string(S, N-1, Len, PP);
         false ->
-            [leaf(Sl)|write_a_string(lists:nthtail(length(SS), S), Len, Len)]
+            [flat_leaf(Sl) |
+             write_a_string(lists:nthtail(length(SS), S), Len, Len, PP)]
     end.
 
+flat_leaf(S) ->
+    L = lists:flatten(S),
+    {leaf,length(L),L}.
+
+write_string(S, PP) ->
+    lists:flatten((PP#pp.string_fun)(S)).
+
+write_char(C, PP) ->
+    lists:flatten((PP#pp.char_fun)(C)).
+
 %%
 %% Utilities
 %%
diff --git a/lib/stdlib/src/erl_scan.erl b/lib/stdlib/src/erl_scan.erl
index d880656565..818703284f 100644
--- a/lib/stdlib/src/erl_scan.erl
+++ b/lib/stdlib/src/erl_scan.erl
@@ -55,7 +55,14 @@
          token_info/1,token_info/2,
          attributes_info/1,attributes_info/2,set_attribute/3]).
 
--export_type([error_info/0, line/0, return_cont/0, tokens_result/0]).
+%%% Private
+-export([continuation_location/1]).
+
+-export_type([error_info/0,
+              line/0,
+              options/0,
+              return_cont/0,
+              tokens_result/0]).
 
 %%%
 %%% Defines and type definitions
@@ -74,7 +81,8 @@
 -type location() :: line() | {line(),column()}.
 -type resword_fun() :: fun((atom()) -> boolean()).
 -type option() :: 'return' | 'return_white_spaces' | 'return_comments'
-                | 'text' | {'reserved_word_fun', resword_fun()}.
+                | 'text' | {'reserved_word_fun', resword_fun()}
+                | 'unicode'.
 -type options() :: option() | [option()].
 -type symbol() :: atom() | float() | integer() | string().
 -type info_line() :: integer() | term().
@@ -95,7 +103,8 @@
         {resword_fun = fun reserved_word/1 :: resword_fun(),
          ws          = false               :: boolean(),
          comment     = false               :: boolean(),
-         text        = false               :: boolean()}).
+         text        = false               :: boolean(),
+         unicode     = false               :: boolean()}).
 
 %%----------------------------------------------------------------------------
 
@@ -183,6 +192,11 @@ tokens({erl_scan_continuation,Cs,Col,Toks,Line,St,Any,Fun},
        CharSpec, _Loc, _Opts) ->
     tokens1(Cs++CharSpec, St, Line, Col, Toks, Fun, Any).
 
+continuation_location({erl_scan_continuation,_,no_col,_,Line,_,_,_}) ->
+    Line;
+continuation_location({erl_scan_continuation,_,Col,_,Line,_,_,_}) ->
+    {Line,Col}.
+
 -type attribute_item() :: 'column' | 'length' | 'line'
                         | 'location' | 'text'.
 -type info_location() :: location() | term().
@@ -322,13 +336,20 @@ string_thing(_) -> "string".
          (C >= $\000 andalso C =< $\s orelse C >= $\200 andalso C =< $\240)).
 -define(DIGIT(C), C >= $0, C =< $9).
 -define(CHAR(C), is_integer(C), C >= 0).
-
-%% A workaround: Unicode strings are not returned as strings, but as
-%% lists of integers. For instance, "b\x{aaa}c" => [98,2730,99]. This
-%% is to protect the system from character codes greater than 255. To
-%% be removed. Search for UNI to find workaround code.
+-define(UNICODE(C),
+         (C >= 0 andalso C < 16#D800 orelse
+          C > 16#DFFF andalso C < 16#FFFE orelse
+          C > 16#FFFF andalso C =< 16#10FFFF)).
+
+%% When the option 'unicode' is false: return Unicode strings as lists
+%% of integers and Unicode characters as integers. For instance,
+%% erl_scan:string("\"b\x{aaa}c\".") is equivalent to
+%% erl_scan:string("[98,2730,99]."). This is to protect the caller
+%% from character codes greater than 255. Search for UNI to find code
+%% implementing this "feature". The 'unicode' option is undocumented
+%% and will probably be removed later.
 -define(NO_UNICODE, 0).
--define(UNI255(C), (C) =< 16#ff).
+-define(UNI255(C), (C =< 16#ff)).
 
 options(Opts0) when is_list(Opts0) ->
     Opts = lists:foldr(fun expand_opt/2, [], Opts0),
@@ -342,10 +363,12 @@ options(Opts0) when is_list(Opts0) ->
     Comment = proplists:get_bool(return_comments, Opts),
     WS = proplists:get_bool(return_white_spaces, Opts),
     Txt = proplists:get_bool(text, Opts),
+    Unicode = proplists:get_bool(unicode, Opts),
     #erl_scan{resword_fun = RW_fun,
               comment     = Comment,
               ws          = WS,
-              text        = Txt};
+              text        = Txt,
+              unicode     = Unicode};
 options(Opt) ->
     options([Opt]).
 
@@ -626,15 +649,12 @@ scan1([$~|Cs], St, Line, Col, Toks) ->
 scan1([$&|Cs], St, Line, Col, Toks) ->
     tok2(Cs, St, Line, Col, Toks, "&", '&', 1);
 %% End of optimization.
-scan1([C|Cs], St, Line, Col, Toks) when ?CHAR(C) ->
+scan1([C|Cs], St, Line, Col, Toks) when ?CHAR(C), ?UNI255(C) ->
     Str = [C],
-    case catch list_to_atom(Str) of
-        Sym when is_atom(Sym) ->
-            tok2(Cs, St, Line, Col, Toks, Str, Sym, 1);
-        _ ->
-            Ncol = incr_column(Col, 1),
-            scan_error({illegal,character}, Line, Col, Line, Ncol, Cs)
-    end;
+    tok2(Cs, St, Line, Col, Toks, Str, list_to_atom(Str), 1);
+scan1([C|Cs], _St, Line, Col, _Toks) when ?CHAR(C) ->
+    Ncol = incr_column(Col, 1),
+    scan_error({illegal,character}, Line, Col, Line, Ncol, Cs);
 scan1([]=Cs, _St, Line, Col, Toks) ->
     {more,{Cs,Col,Toks,Line,[],fun scan/6}};
 scan1(eof=Cs, _St, Line, Col, Toks) ->
@@ -832,32 +852,44 @@ scan_char([$\\|Cs]=Cs0, St, Line, Col, Toks) ->
         {eof,Ncol} ->
             scan_error(char, Line, Col, Line, Ncol, eof);
         {nl,Val,Str,Ncs,Ncol} ->
-            Attrs = attributes(Line, Col, St, "$\\"++Str),
+            Attrs = attributes(Line, Col, St, "$\\"++Str), %"
             Ntoks = [{char,Attrs,Val}|Toks],
             scan1(Ncs, St, Line+1, Ncol, Ntoks);
         {unicode,Val,Str,Ncs,Ncol} ->
-            Attrs = attributes(Line, Col, St, "$\\"++Str),
-            Ntoks = [{integer,Attrs,Val}|Toks], % UNI
+            Attrs = attributes(Line, Col, St, "$\\"++Str), %"
+            Tag = char_tag(Val, St), % UNI
+            Ntoks = [{Tag,Attrs,Val}|Toks],
             scan1(Ncs, St, Line, Ncol, Ntoks);
         {Val,Str,Ncs,Ncol} ->
-            Attrs = attributes(Line, Col, St, "$\\"++Str),
+            Attrs = attributes(Line, Col, St, "$\\"++Str), %"
             Ntoks = [{char,Attrs,Val}|Toks],
             scan1(Ncs, St, Line, Ncol, Ntoks)
     end;
 scan_char([$\n=C|Cs], St, Line, Col, Toks) ->
     Attrs = attributes(Line, Col, St, [$$,C]),
     scan1(Cs, St, Line+1, new_column(Col, 1), [{char,Attrs,C}|Toks]);
-scan_char([C|Cs], St, Line, Col, Toks) when ?CHAR(C) ->
-    Tag = if ?UNI255(C) -> char; true -> integer end, % UNI
+scan_char([C|Cs], St, Line, Col, Toks) when ?UNICODE(C) ->
+    Tag = char_tag(C, St), % UNI
     Attrs = attributes(Line, Col, St, [$$,C]),
     scan1(Cs, St, Line, incr_column(Col, 2), [{Tag,Attrs,C}|Toks]);
+scan_char([C|_Cs], _St, Line, Col, _Toks) when ?CHAR(C) ->
+    scan_error({illegal,character}, Line, Col, Line, incr_column(Col, 1), eof);
 scan_char([], _St, Line, Col, Toks) ->
     {more,{[$$],Col,Toks,Line,[],fun scan/6}};
 scan_char(eof, _St, Line, Col, _Toks) ->
     scan_error(char, Line, Col, Line, incr_column(Col, 1), eof).
 
+-compile({inline,[char_tag/2]}).
+
+char_tag(C, _St) when ?UNI255(C) ->
+    char;
+char_tag(_C, #erl_scan{unicode = true}) ->
+    char;
+char_tag(_C, _St) ->
+    integer.
+
 scan_string(Cs, St, Line, Col, Toks, {Wcs,Str,Line0,Col0,Uni0}) ->
-    case scan_string0(Cs, St, Line, Col, $\", Str, Wcs, Uni0) of
+    case scan_string0(Cs, St, Line, Col, $\", true, Str, Wcs, Uni0) of %"
         {more,Ncs,Nline,Ncol,Nstr,Nwcs,Uni} ->
             State = {Nwcs,Nstr,Line0,Col0,Uni},
             {more,{Ncs,Ncol,Toks,Nline,State,fun scan_string/6}};
@@ -865,8 +897,9 @@ scan_string(Cs, St, Line, Col, Toks, {Wcs,Str,Line0,Col0,Uni0}) ->
             scan_error(Error, Nline, Ncol, Nline, EndCol, Ncs);
         {error,Nline,Ncol,Nwcs,Ncs} ->
             Estr = string:substr(Nwcs, 1, 16), % Expanded escape chars.
-            scan_error({string,$\",Estr}, Line0, Col0, Nline, Ncol, Ncs);
-        {Ncs,Nline,Ncol,Nstr,Nwcs,?NO_UNICODE} ->
+            scan_error({string,$\",Estr}, Line0, Col0, Nline, Ncol, Ncs); %"
+        {Ncs,Nline,Ncol,Nstr,Nwcs,Uni} when Uni =:= ?NO_UNICODE;
+                                            St#erl_scan.unicode ->
             Attrs = attributes(Line0, Col0, St, Nstr),
             scan1(Ncs, St, Nline, Ncol, [{string,Attrs,Nwcs}|Toks]);
         {Ncs,Nline,Ncol,Nstr,_Nwcs,_Uni} ->
@@ -918,7 +951,8 @@ unicode_tokens(Line, Col, Str, Val, St, Toks, Cs, Cline, Ccol) ->
     [{',',attributes(Cline, Ccol, St, "")} || Cs =/= "\""] ++ [Token|Toks].
 
 scan_qatom(Cs, St, Line, Col, Toks, {Wcs,Str,Line0,Col0,Uni0}) ->
-    case scan_string0(Cs, St, Line, Col, $\', Str, Wcs, Uni0) of
+    AllowUni = St#erl_scan.unicode,
+    case scan_string0(Cs, St, Line, Col, $\', AllowUni, Str, Wcs, Uni0) of %'
         {more,Ncs,Nline,Ncol,Nstr,Nwcs,Uni} ->
             State = {Nwcs,Nstr,Line0,Col0,Uni},
             {more,{Ncs,Ncol,Toks,Nline,State,fun scan_qatom/6}};
@@ -926,8 +960,9 @@ scan_qatom(Cs, St, Line, Col, Toks, {Wcs,Str,Line0,Col0,Uni0}) ->
             scan_error(Error, Nline, Ncol, Nline, EndCol, Ncs);
         {error,Nline,Ncol,Nwcs,Ncs} ->
             Estr = string:substr(Nwcs, 1, 16), % Expanded escape chars.
-            scan_error({string,$\',Estr}, Line0, Col0, Nline, Ncol, Ncs);
-        {Ncs,Nline,Ncol,Nstr,Nwcs,?NO_UNICODE} ->
+            scan_error({string,$\',Estr}, Line0, Col0, Nline, Ncol, Ncs); %'
+        {Ncs,Nline,Ncol,Nstr,Nwcs,Uni} ->
+            true = Uni =:= ?NO_UNICODE orelse AllowUni,
             case catch list_to_atom(Nwcs) of
                 A when is_atom(A) ->
                     Attrs = attributes(Line0, Col0, St, Nstr),
@@ -937,38 +972,40 @@ scan_qatom(Cs, St, Line, Col, Toks, {Wcs,Str,Line0,Col0,Uni0}) ->
             end
     end.
 
-scan_string0(Cs, #erl_scan{text=false}, Line, no_col=Col, Q, [], Wcs, Uni) ->
-    scan_string_no_col(Cs, Line, Col, Q, Wcs, Uni);
-scan_string0(Cs, #erl_scan{text=true}, Line, no_col=Col, Q, Str, Wcs, Uni) ->
-    scan_string1(Cs, Line, Col, Q, Str, Wcs, Uni);
-scan_string0(Cs, _St, Line, Col, Q, [], Wcs, Uni) ->
-    scan_string_col(Cs, Line, Col, Q, Wcs, Uni);
-scan_string0(Cs, _St, Line, Col, Q, Str, Wcs, Uni) ->
-    scan_string1(Cs, Line, Col, Q, Str, Wcs, Uni).
+scan_string0(Cs, #erl_scan{text=false}, Line, no_col=Col, Q, U, [], Wcs, Uni) ->
+    scan_string_no_col(Cs, Line, Col, Q, U, Wcs, Uni);
+scan_string0(Cs, #erl_scan{text=true}, Line, no_col=Col, Q, U, Str, Wcs, Uni) ->
+    scan_string1(Cs, Line, Col, Q, U, Str, Wcs, Uni);
+scan_string0(Cs, _St, Line, Col, Q, U, [], Wcs, Uni) ->
+    scan_string_col(Cs, Line, Col, Q, U, Wcs, Uni);
+scan_string0(Cs, _St, Line, Col, Q, U, Str, Wcs, Uni) ->
+    scan_string1(Cs, Line, Col, Q, U, Str, Wcs, Uni).
 
 %% Optimization. Col =:= no_col.
-scan_string_no_col([Q|Cs], Line, Col, Q, Wcs, Uni) ->
+scan_string_no_col([Q|Cs], Line, Col, Q, _U, Wcs, Uni) ->
     {Cs,Line,Col,_DontCare=[],lists:reverse(Wcs),Uni};
-scan_string_no_col([$\n=C|Cs], Line, Col, Q, Wcs, Uni) ->
-    scan_string_no_col(Cs, Line+1, Col, Q, [C|Wcs], Uni);
-scan_string_no_col([C|Cs], Line, Col, Q, Wcs, Uni) when C =/= $\\,
-                                                        ?CHAR(C), ?UNI255(C) ->
-    scan_string_no_col(Cs, Line, Col, Q, [C|Wcs], Uni);
-scan_string_no_col(Cs, Line, Col, Q, Wcs, Uni) ->
-    scan_string1(Cs, Line, Col, Q, Wcs, Wcs, Uni).
+scan_string_no_col([$\n=C|Cs], Line, Col, Q, U, Wcs, Uni) ->
+    scan_string_no_col(Cs, Line+1, Col, Q, U, [C|Wcs], Uni);
+scan_string_no_col([C|Cs], Line, Col, Q, U, Wcs, Uni) when C =/= $\\,
+                                                           ?CHAR(C),
+                                                           ?UNI255(C) ->
+    scan_string_no_col(Cs, Line, Col, Q, U, [C|Wcs], Uni);
+scan_string_no_col(Cs, Line, Col, Q, U, Wcs, Uni) ->
+    scan_string1(Cs, Line, Col, Q, U, Wcs, Wcs, Uni).
 
 %% Optimization. Col =/= no_col.
-scan_string_col([Q|Cs], Line, Col, Q, Wcs0, Uni) ->
+scan_string_col([Q|Cs], Line, Col, Q, _U, Wcs0, Uni) ->
     Wcs = lists:reverse(Wcs0),
     Str = [Q|Wcs++[Q]],
     {Cs,Line,Col+1,Str,Wcs,Uni};
-scan_string_col([$\n=C|Cs], Line, _xCol, Q, Wcs, Uni) ->
-    scan_string_col(Cs, Line+1, 1, Q, [C|Wcs], Uni);
-scan_string_col([C|Cs], Line, Col, Q, Wcs, Uni) when C =/= $\\,
-                                                     ?CHAR(C), ?UNI255(C) ->
-    scan_string_col(Cs, Line, Col+1, Q, [C|Wcs], Uni);
-scan_string_col(Cs, Line, Col, Q, Wcs, Uni) ->
-    scan_string1(Cs, Line, Col, Q, Wcs, Wcs, Uni).
+scan_string_col([$\n=C|Cs], Line, _xCol, Q, U, Wcs, Uni) ->
+    scan_string_col(Cs, Line+1, 1, Q, U, [C|Wcs], Uni);
+scan_string_col([C|Cs], Line, Col, Q, U, Wcs, Uni) when C =/= $\\,
+                                                        ?CHAR(C),
+                                                        ?UNI255(C) ->
+    scan_string_col(Cs, Line, Col+1, Q, U, [C|Wcs], Uni);
+scan_string_col(Cs, Line, Col, Q, U, Wcs, Uni) ->
+    scan_string1(Cs, Line, Col, Q, U, Wcs, Wcs, Uni).
 
 %% UNI_STR is to be replaced by STR when the Unicode-string-to-list
 %% workaround is eventually removed.
@@ -979,14 +1016,14 @@ scan_string_col(Cs, Line, Col, Q, Wcs, Uni) ->
 %% but then the end location of the error tuple would not correspond
 %% to the start location of the returned Rest string. (Maybe the end
 %% location could be modified, but that too is ugly.)
-scan_string1([Q|Cs], Line, Col, Q, Str0, Wcs0, Uni) ->
+scan_string1([Q|Cs], Line, Col, Q, _U, Str0, Wcs0, Uni) ->
     Wcs = lists:reverse(Wcs0),
     Str = ?UNI_STR(Col, [Q|lists:reverse(Str0, [Q])]),
     {Cs,Line,incr_column(Col, 1),Str,Wcs,Uni};
-scan_string1([$\n=C|Cs], Line, Col, Q, Str, Wcs, Uni) ->
+scan_string1([$\n=C|Cs], Line, Col, Q, U, Str, Wcs, Uni) ->
     Ncol = new_column(Col, 1),
-    scan_string1(Cs, Line+1, Ncol, Q, ?UNI_STR(Col, [C|Str]), [C|Wcs], Uni);
-scan_string1([$\\|Cs]=Cs0, Line, Col, Q, Str, Wcs, Uni) ->
+    scan_string1(Cs, Line+1, Ncol, Q, U, ?UNI_STR(Col, [C|Str]), [C|Wcs], Uni);
+scan_string1([$\\|Cs]=Cs0, Line, Col, Q, U, Str, Wcs, Uni) ->
     case scan_escape(Cs, Col) of
         more ->
             {more,Cs0,Line,Col,Str,Wcs,Uni};
@@ -997,31 +1034,33 @@ scan_string1([$\\|Cs]=Cs0, Line, Col, Q, Str, Wcs, Uni) ->
         {nl,Val,ValStr,Ncs,Ncol} ->
             Nstr = ?UNI_STR(Ncol, lists:reverse(ValStr, [$\\|Str])),
             Nwcs = [Val|Wcs],
-            scan_string1(Ncs, Line+1, Ncol, Q, Nstr, Nwcs, Uni);
-        {unicode,_Val,_ValStr,Ncs,Ncol} when Q =:= $' -> %' Emacs
+            scan_string1(Ncs, Line+1, Ncol, Q, U, Nstr, Nwcs, Uni);
+        {unicode,_Val,_ValStr,Ncs,Ncol} when not U -> %' Emacs
             {char_error,Ncs,{illegal,character},Line,Col,incr_column(Ncol, 1)};
         {unicode,Val,ValStr,Ncs,Ncol} -> % UNI. Uni is set to Val.
             Nstr = ?UNI_STR(Ncol, lists:reverse(ValStr, [$\\|Str])),
             Nwcs = [Val|Wcs], % not used
-            scan_string1(Ncs, Line, incr_column(Ncol, 1), Q, Nstr, Nwcs, Val);
+            scan_string1(Ncs, Line, incr_column(Ncol, 1), Q, U, Nstr, Nwcs, Val);
         {Val,ValStr,Ncs,Ncol} ->
             Nstr = ?UNI_STR(Ncol, lists:reverse(ValStr, [$\\|Str])),
             Nwcs = [Val|Wcs],
-            scan_string1(Ncs, Line, incr_column(Ncol, 1), Q, Nstr, Nwcs, Uni)
+            scan_string1(Ncs, Line, incr_column(Ncol, 1), Q, U, Nstr, Nwcs, Uni)
     end;
-scan_string1([C|Cs], Line, no_col=Col, Q, Str, Wcs, Uni) when ?CHAR(C),
-                                                              ?UNI255(C) ->
-    %% scan_string1(Cs, Line, Col, Q, Str, [C|Wcs], Uni);
-    scan_string1(Cs, Line, Col, Q, [C|Str], [C|Wcs], Uni); % UNI
-scan_string1([C|Cs], Line, Col, Q, Str, Wcs, Uni) when ?CHAR(C), ?UNI255(C) ->
-    scan_string1(Cs, Line, Col+1, Q, [C|Str], [C|Wcs], Uni);
-scan_string1([C|Cs], Line, Col, $', _Str, _Wcs, _Uni) when ?CHAR(C) -> %' UNI
+scan_string1([C|Cs], Line, no_col=Col, Q, U, Str, Wcs, Uni) when ?CHAR(C),
+                                                                 ?UNI255(C) ->
+    %% scan_string1(Cs, Line, Col, Q, U, Str, [C|Wcs], Uni);
+    scan_string1(Cs, Line, Col, Q, U, [C|Str], [C|Wcs], Uni); % UNI
+scan_string1([C|Cs], Line, Col, Q, U, Str, Wcs, Uni) when ?CHAR(C), ?UNI255(C) ->
+    scan_string1(Cs, Line, Col+1, Q, U, [C|Str], [C|Wcs], Uni);
+scan_string1([C|Cs], Line, Col, _Q, false, _Str, _Wcs, _Uni) when ?CHAR(C) -> %' UNI
     {char_error,Cs,{illegal,character},Line,Col,incr_column(Col, 1)};
-scan_string1([C|Cs], Line, Col, Q, Str, Wcs, _Uni) when ?CHAR(C) -> % UNI
-    scan_string1(Cs, Line, incr_column(Col, 1), Q, [C|Str], [C|Wcs], C);
-scan_string1([]=Cs, Line, Col, _Q, Str, Wcs, Uni) ->
+scan_string1([C|Cs], Line, Col, Q, U, Str, Wcs, _Uni) when ?UNICODE(C) ->
+    scan_string1(Cs, Line, incr_column(Col, 1), Q, U, [C|Str], [C|Wcs], C);
+scan_string1([C|Cs], Line, Col, _Q, _U, _Str, _Wcs, _Uni) when ?CHAR(C) -> % UNI
+    {char_error,Cs,{illegal,character},Line,Col,incr_column(Col, 1)};
+scan_string1([]=Cs, Line, Col, _Q, _U, Str, Wcs, Uni) ->
     {more,Cs,Line,Col,Str,Wcs,Uni};
-scan_string1(eof, Line, Col, _Q, _Str, Wcs, _Uni) ->
+scan_string1(eof, Line, Col, _Q, _U, _Str, Wcs, _Uni) ->
     {error,Line,Col,lists:reverse(Wcs),eof}.
 
 -define(OCT(C), C >= $0, C =< $7).
@@ -1072,8 +1111,10 @@ scan_escape([$\n=C|Cs], Col) ->
 scan_escape([C0|Cs], Col) when ?CHAR(C0), ?UNI255(C0) ->
     C = escape_char(C0),
     {C,?UNI_STR(Col, [C0]),Cs,incr_column(Col, 1)};
-scan_escape([C|Cs], Col) when ?CHAR(C) -> % UNI
+scan_escape([C|Cs], Col) when ?UNICODE(C) ->
     {unicode,C,?UNI_STR(Col, [C]),Cs,incr_column(Col, 1)};
+scan_escape([C|Cs], Col) when ?CHAR(C) -> % UNI
+    {error,Cs,{illegal,character},incr_column(Col, 1)};
 scan_escape([], _Col) ->
     more;
 scan_escape(eof, Col) ->
@@ -1091,7 +1132,7 @@ scan_esc_end([$}|Cs], Col, Wcs0, B, Str0) ->
     case catch erlang:list_to_integer(Wcs, B) of
         Val when Val =< 16#FF ->
             {Val,?UNI_STR(Col, Str0++Wcs++[$}]),Cs,incr_column(Col, 1)};
-        Val when Val =< 16#10FFFF ->
+        Val when ?UNICODE(Val) ->
             {unicode,Val,?UNI_STR(Col, Str0++Wcs++[$}]),Cs,incr_column(Col,1)};
         _ ->
             {error,Cs,{illegal,character},incr_column(Col, 1)}
@@ -1197,18 +1238,36 @@ float_end(Cs, St, Line, Col, Toks, Ncs0) ->
             scan_error({illegal,float}, Line, Col, Line, Ncol, Cs)
     end.
 
-skip_comment([C|Cs], St, Line, Col, Toks, N) when C =/= $\n, ?CHAR(C) ->
-    skip_comment(Cs, St, Line, Col, Toks, N+1);
-skip_comment([]=Cs, _St, Line, Col, Toks, N) ->
-    {more,{Cs,Col,Toks,Line,N,fun skip_comment/6}};
 skip_comment(Cs, St, Line, Col, Toks, N) ->
+    skip_comment(Cs, St, Line, Col, Toks, N, St#erl_scan.unicode).
+
+skip_comment([C|Cs], St, Line, Col, Toks, N, U) when C =/= $\n, ?CHAR(C) ->
+    case ?UNI255(C) orelse U andalso ?UNICODE(C) of
+        true ->
+            skip_comment(Cs, St, Line, Col, Toks, N+1, U);
+        false ->
+            Ncol = incr_column(Col, N+1),
+            scan_error({illegal,character}, Line, Col, Line, Ncol, Cs)
+    end;
+skip_comment([]=Cs, _St, Line, Col, Toks, N, _U) ->
+    {more,{Cs,Col,Toks,Line,N,fun skip_comment/6}};
+skip_comment(Cs, St, Line, Col, Toks, N, _U) ->
     scan1(Cs, St, Line, incr_column(Col, N), Toks).
 
-scan_comment([C|Cs], St, Line, Col, Toks, Ncs) when C =/= $\n, ?CHAR(C) ->
-    scan_comment(Cs, St, Line, Col, Toks, [C|Ncs]);
-scan_comment([]=Cs, _St, Line, Col, Toks, Ncs) ->
+scan_comment(Cs, St, Line, Col, Toks, Ncs) ->
+    scan_comment(Cs, St, Line, Col, Toks, Ncs, St#erl_scan.unicode).
+
+scan_comment([C|Cs], St, Line, Col, Toks, Ncs, U) when C =/= $\n, ?CHAR(C) ->
+    case ?UNI255(C) orelse U andalso ?UNICODE(C) of
+        true ->
+            scan_comment(Cs, St, Line, Col, Toks, [C|Ncs], U);
+        false ->
+            Ncol = incr_column(Col, length(Ncs)+1),
+            scan_error({illegal,character}, Line, Col, Line, Ncol, Cs)
+    end;
+scan_comment([]=Cs, _St, Line, Col, Toks, Ncs, _U) ->
     {more,{Cs,Col,Toks,Line,Ncs,fun scan_comment/6}};
-scan_comment(Cs, St, Line, Col, Toks, Ncs0) ->
+scan_comment(Cs, St, Line, Col, Toks, Ncs0, _U) ->
     Ncs = lists:reverse(Ncs0),
     tok3(Cs, St, Line, Col, Toks, comment, Ncs, Ncs).
 
diff --git a/lib/stdlib/src/escript.erl b/lib/stdlib/src/escript.erl
index 498d850df3..99a9d138ac 100644
--- a/lib/stdlib/src/escript.erl
+++ b/lib/stdlib/src/escript.erl
@@ -710,7 +710,7 @@ epp_parse_file2(Epp, S, Forms, Parsed) ->
                     epp_parse_file(Epp, S, [Form | Forms])
             end;
         {error,{Ln,Mod,Args}} = Form ->
-            io:format("~s:~w: ~s\n",
+            io:format("~s:~w: ~ts\n",
                       [S#state.file,Ln,Mod:format_error(Args)]),
             epp_parse_file(Epp, S#state{n_errors = S#state.n_errors + 1}, [Form | Forms]);
         {eof, _LastLine} = Eof ->
@@ -780,10 +780,10 @@ report_errors(Errors) ->
                   Errors).
 
 list_errors(F, [{Line,Mod,E}|Es]) ->
-    io:fwrite("~s:~w: ~s\n", [F,Line,Mod:format_error(E)]),
+    io:fwrite("~s:~w: ~ts\n", [F,Line,Mod:format_error(E)]),
     list_errors(F, Es);
 list_errors(F, [{Mod,E}|Es]) ->
-    io:fwrite("~s: ~s\n", [F,Mod:format_error(E)]),
+    io:fwrite("~s: ~ts\n", [F,Mod:format_error(E)]),
     list_errors(F, Es);
 list_errors(_F, []) -> ok.
 
@@ -795,10 +795,10 @@ report_warnings(Ws0) ->
     lists:foreach(fun({_,Str}) -> io:put_chars(Str) end, Ws).
 
 format_message(F, [{Line,Mod,E}|Es]) ->
-    M = {{F,Line},io_lib:format("~s:~w: Warning: ~s\n", [F,Line,Mod:format_error(E)])},
+    M = {{F,Line},io_lib:format("~s:~w: Warning: ~ts\n", [F,Line,Mod:format_error(E)])},
     [M|format_message(F, Es)];
 format_message(F, [{Mod,E}|Es]) ->
-    M = {none,io_lib:format("~s: Warning: ~s\n", [F,Mod:format_error(E)])},
+    M = {none,io_lib:format("~s: Warning: ~ts\n", [F,Mod:format_error(E)])},
     [M|format_message(F, Es)];
 format_message(_, []) -> [].
 
@@ -851,12 +851,27 @@ eval_exprs([E|Es], Bs0, Lf, Ef, RBs) ->
     eval_exprs(Es, Bs, Lf, Ef, RBs).
 
 format_exception(Class, Reason) ->
+    Enc = encoding(),
+    P = case Enc of
+            latin1 -> "P";
+            _ -> "tP"
+        end,
     PF = fun(Term, I) ->
-                 io_lib:format("~." ++ integer_to_list(I) ++ "P", [Term, 50])
+                 io_lib:format("~." ++ integer_to_list(I) ++ P, [Term, 50])
          end,
     StackTrace = erlang:get_stacktrace(),
     StackFun = fun(M, _F, _A) -> (M =:= erl_eval) or (M =:= ?MODULE) end,
-    lib:format_exception(1, Class, Reason, StackTrace, StackFun, PF).
+    lib:format_exception(1, Class, Reason, StackTrace, StackFun, PF, Enc).
+
+encoding() ->
+    [{encoding, Encoding}] = enc(),
+    Encoding.
+
+enc() ->
+    case lists:keyfind(encoding, 1, io:getopts()) of
+        false -> [{encoding,latin1}]; % should never happen
+        Enc -> [Enc]
+    end.
 
 fatal(Str) ->
     throw(Str).
diff --git a/lib/stdlib/src/io.erl b/lib/stdlib/src/io.erl
index 9f65bbfa3a..2644083733 100644
--- a/lib/stdlib/src/io.erl
+++ b/lib/stdlib/src/io.erl
@@ -1,7 +1,7 @@
 %%
 %% %CopyrightBegin%
 %%
-%% Copyright Ericsson AB 1996-2011. All Rights Reserved.
+%% Copyright Ericsson AB 1996-2012. 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
@@ -22,14 +22,15 @@
 	 get_chars/2,get_chars/3,get_line/1,get_line/2,
 	 get_password/0, get_password/1,
 	 setopts/1, setopts/2, getopts/0, getopts/1]).
--export([write/1,write/2,read/1,read/2,read/3]).
+-export([write/1,write/2,read/1,read/2,read/3,read/4]).
 -export([columns/0,columns/1,rows/0,rows/1]).
 -export([fwrite/1,fwrite/2,fwrite/3,fread/2,fread/3,
 	 format/1,format/2,format/3]).
--export([scan_erl_exprs/1,scan_erl_exprs/2,scan_erl_exprs/3,
-	 scan_erl_form/1,scan_erl_form/2,scan_erl_form/3,
+-export([scan_erl_exprs/1,scan_erl_exprs/2,scan_erl_exprs/3,scan_erl_exprs/4,
+	 scan_erl_form/1,scan_erl_form/2,scan_erl_form/3,scan_erl_form/4,
 	 parse_erl_exprs/1,parse_erl_exprs/2,parse_erl_exprs/3,
-	 parse_erl_form/1,parse_erl_form/2,parse_erl_form/3]).
+         parse_erl_exprs/4,parse_erl_form/1,parse_erl_form/2,
+         parse_erl_form/3,parse_erl_form/4]).
 -export([request/1,request/2,requests/1,requests/2]).
 
 -export_type([device/0, format/0]).
@@ -256,8 +257,21 @@ read(Io, Prompt) ->
               | {'eof', EndLine :: line()}
               | {'error', ErrorInfo :: erl_scan:error_info(), ErrorLine :: line()}.
 
-read(Io, Prompt, StartLine) when is_integer(StartLine) ->
-    case request(Io, {get_until,unicode,Prompt,erl_scan,tokens,[StartLine]}) of
+read(Io, Prompt, Pos0) ->
+    read(Io, Prompt, Pos0, []).
+
+-spec read(IoDevice, Prompt, StartLine, Options) -> Result when
+      IoDevice :: device(),
+      Prompt :: prompt(),
+      StartLine :: line(),
+      Options :: erl_scan:options(),
+      Result :: {'ok', Term :: term(), EndLine :: line()}
+              | {'eof', EndLine :: line()}
+              | {'error', ErrorInfo :: erl_scan:error_info(), ErrorLine :: line()}.
+
+read(Io, Prompt, Pos0, Options) when is_integer(Pos0), is_list(Options) ->
+    Args = [Pos0,Options],
+    case request(Io, {get_until,unicode,Prompt,erl_scan,tokens,Args}) of
 	{ok,Toks,EndLine} ->
             case erl_parse:parse_term(Toks) of
                 {ok,Term} -> {ok,Term,EndLine};
@@ -368,7 +382,17 @@ scan_erl_exprs(Io, Prompt) ->
       Result :: erl_scan:tokens_result() | request_error().
 
 scan_erl_exprs(Io, Prompt, Pos0) ->
-    request(Io, {get_until,unicode,Prompt,erl_scan,tokens,[Pos0]}).
+    scan_erl_exprs(Io, Prompt, Pos0, []).
+
+-spec scan_erl_exprs(Device, Prompt, StartLine, Options) -> Result when
+      Device :: device(),
+      Prompt :: prompt(),
+      StartLine :: line(),
+      Options :: erl_scan:options(),
+      Result :: erl_scan:tokens_result() | request_error().
+
+scan_erl_exprs(Io, Prompt, Pos0, Options) ->
+    request(Io, {get_until,unicode,Prompt,erl_scan,tokens,[Pos0,Options]}).
 
 -spec scan_erl_form(Prompt) -> Result when
       Prompt :: prompt(),
@@ -392,7 +416,17 @@ scan_erl_form(Io, Prompt) ->
       Result :: erl_scan:tokens_result() | request_error().
 
 scan_erl_form(Io, Prompt, Pos0) ->
-    request(Io, {get_until,unicode,Prompt,erl_scan,tokens,[Pos0]}).
+    scan_erl_form(Io, Prompt, Pos0, []).
+
+-spec scan_erl_form(IoDevice, Prompt, StartLine, Options) -> Result when
+      IoDevice :: device(),
+      Prompt :: prompt(),
+      StartLine :: line(),
+      Options :: erl_scan:options(),
+      Result :: erl_scan:tokens_result() | request_error().
+
+scan_erl_form(Io, Prompt, Pos0, Options) ->
+    request(Io, {get_until,unicode,Prompt,erl_scan,tokens,[Pos0,Options]}).
 
 %% Parsing Erlang code.
 
@@ -423,7 +457,17 @@ parse_erl_exprs(Io, Prompt) ->
       Result :: parse_ret().
 
 parse_erl_exprs(Io, Prompt, Pos0) ->
-    case request(Io, {get_until,unicode,Prompt,erl_scan,tokens,[Pos0]}) of
+    parse_erl_exprs(Io, Prompt, Pos0, []).
+
+-spec parse_erl_exprs(IoDevice, Prompt, StartLine, Options) -> Result when
+      IoDevice :: device(),
+      Prompt :: prompt(),
+      StartLine :: line(),
+      Options :: erl_scan:options(),
+      Result :: parse_ret().
+
+parse_erl_exprs(Io, Prompt, Pos0, Options) ->
+    case request(Io, {get_until,unicode,Prompt,erl_scan,tokens,[Pos0,Options]}) of
 	{ok,Toks,EndPos} ->
 	    case erl_parse:parse_exprs(Toks) of
 		{ok,Exprs} -> {ok,Exprs,EndPos};
@@ -460,7 +504,18 @@ parse_erl_form(Io, Prompt) ->
       Result :: parse_form_ret().
 
 parse_erl_form(Io, Prompt, Pos0) ->
-    case request(Io, {get_until,unicode,Prompt,erl_scan,tokens,[Pos0]}) of
+    parse_erl_form(Io, Prompt, Pos0, []).
+
+-spec parse_erl_form(IoDevice, Prompt, StartLine, Options) -> Result when
+      IoDevice :: device(),
+      Prompt :: prompt(),
+      StartLine :: line(),
+      Options :: erl_scan:options(),
+      Result :: parse_form_ret().
+
+parse_erl_form(Io, Prompt, Pos0, Options) ->
+    Args = [Pos0, Options],
+    case request(Io, {get_until,unicode,Prompt,erl_scan,tokens,Args}) of
 	{ok,Toks,EndPos} ->
 	    case erl_parse:parse_form(Toks) of
 		{ok,Exprs} -> {ok,Exprs,EndPos};
diff --git a/lib/stdlib/src/io_lib.erl b/lib/stdlib/src/io_lib.erl
index 513d904c39..5f57a2fa42 100644
--- a/lib/stdlib/src/io_lib.erl
+++ b/lib/stdlib/src/io_lib.erl
@@ -64,7 +64,10 @@
 
 -export([write/1,write/2,write/3,nl/0,format_prompt/1]).
 -export([write_atom/1,write_string/1,write_string/2,write_unicode_string/1,
-	 write_unicode_string/2, write_char/1, write_unicode_char/1]).
+         write_unicode_string/2, write_char/1, write_unicode_char/1]).
+
+-export([write_unicode_string_as_latin1/1, write_unicode_string_as_latin1/2,
+         write_unicode_char_as_latin1/1]).
 
 -export([quote_atom/2, char_list/1, unicode_char_list/1,
 	 deep_char_list/1, deep_unicode_char_list/1,
@@ -75,11 +78,13 @@
 	 collect_line/2, collect_line/3, collect_line/4,
 	 get_until/3, get_until/4]).
 
--export_type([chars/0, continuation/0]).
+-export_type([chars/0, unicode_chars/0, unicode_string/0, continuation/0]).
 
 %%----------------------------------------------------------------------
 
 -type chars() :: [char() | chars()].
+-type unicode_chars() :: [unicode:unicode_char() | unicode_chars()].
+-type unicode_string() :: [unicode:unicode_char()].
 -type depth() :: -1 | non_neg_integer().
 
 -opaque continuation() :: {Format :: string(),
@@ -330,11 +335,32 @@ write_string(S) ->
 write_string(S, Q) ->
     [Q|write_string1(latin1, S, Q)].
 
+%%% There are two functions to write Unicode strings:
+%%% - they both escape control characters < 160;
+%%% - write_unicode_string() never escapes characters >= 160;
+%%% - write_unicode_string_as_latin1() also escapes characters >= 255.
+
+-spec write_unicode_string(UnicodeString) -> unicode_string() when
+      UnicodeString :: unicode_string().
+
 write_unicode_string(S) ->
     write_unicode_string(S, $").   %"
 
+-spec write_unicode_string(unicode_string(), char()) -> unicode_string().
+
 write_unicode_string(S, Q) ->
-    [Q|write_string1(unicode, S, Q)].
+    [Q|write_string1(unicode_as_unicode, S, Q)].
+
+-spec write_unicode_string_as_latin1(UnicodeString) -> string() when
+      UnicodeString :: unicode_string().
+
+write_unicode_string_as_latin1(S) ->
+    write_unicode_string_as_latin1(S, $").   %"
+
+-spec write_unicode_string_as_latin1(unicode_string(), char()) -> string().
+
+write_unicode_string_as_latin1(S, Q) ->
+    [Q|write_string1(unicode_as_latin1, S, Q)].
 
 write_string1(_,[], Q) ->
     [Q];
@@ -347,7 +373,11 @@ string_char(_,C, _, Tail) when C >= $\s, C =< $~ ->
     [C|Tail];
 string_char(latin1,C, _, Tail) when C >= $\240, C =< $\377 ->
     [C|Tail];
-string_char(unicode,C, _, Tail) when C >= $\240 ->
+string_char(unicode_as_unicode,C, _, Tail) when C >= $\240 ->
+    [C|Tail];
+string_char(unicode_as_latin1,C, _, Tail) when C >= $\240, C =< $\377 ->
+    [C|Tail];
+string_char(unicode_as_latin1,C, _, Tail) when C >= $\377 ->
     "\\x{"++erlang:integer_to_list(C, 16)++"}"++Tail;
 string_char(_,$\n, _, Tail) -> [$\\,$n|Tail];	%\n = LF
 string_char(_,$\r, _, Tail) -> [$\\,$r|Tail];	%\r = CR
@@ -374,10 +404,22 @@ write_char($\s) -> "$\\s";			%Must special case this.
 write_char(C) when is_integer(C), C >= $\000, C =< $\377 ->
     [$$|string_char(latin1,C, -1, [])].
 
-write_unicode_char(Ch) when Ch =< 255 ->
-    write_char(Ch);
-write_unicode_char(Uni) ->
-    [$$|string_char(unicode,Uni, -1, [])].
+%%% There are two functions to write a Unicode character:
+%%% - they both escape control characters < 160;
+%%% - write_unicode_char() never escapes characters >= 160;
+%%% - write_unicode_char_as_latin1() also escapes characters >= 255.
+
+-spec write_unicode_char(UnicodeChar) -> unicode_string() when
+      UnicodeChar :: unicode:unicode_char().
+
+write_unicode_char(Uni) when is_integer(Uni), Uni >= $\000 ->
+    [$$|string_char(unicode_as_unicode,Uni, -1, [])].
+
+-spec write_unicode_char_as_latin1(UnicodeChar) -> string() when
+      UnicodeChar :: unicode:unicode_char().
+
+write_unicode_char_as_latin1(Uni) when is_integer(Uni), Uni >= $\000 ->
+    [$$|string_char(unicode_as_latin1,Uni, -1, [])].
 
 %% char_list(CharList)
 %% deep_char_list(CharList)
@@ -392,7 +434,8 @@ char_list([C|Cs]) when is_integer(C), C >= $\000, C =< $\377 ->
 char_list([]) -> true;
 char_list(_) -> false.			%Everything else is false
 
--spec unicode_char_list(term()) -> boolean().
+-spec unicode_char_list(Term) -> boolean() when
+      Term :: term().
 
 unicode_char_list([C|Cs]) when is_integer(C), C >= 0, C < 16#D800; 
        is_integer(C), C > 16#DFFF, C < 16#FFFE;
@@ -417,7 +460,8 @@ deep_char_list([], []) -> true;
 deep_char_list(_, _More) ->			%Everything else is false
     false.
 
--spec deep_unicode_char_list(term()) -> boolean().
+-spec deep_unicode_char_list(Term) -> boolean() when
+      Term :: term().
 
 deep_unicode_char_list(Cs) ->
     deep_unicode_char_list(Cs, []).
@@ -462,7 +506,8 @@ printable_list(_) -> false.			%Everything else is false
 %%  Everything that is not a control character and not invalid unicode 
 %%  will be considered printable.
 
--spec printable_unicode_list(term()) -> boolean().
+-spec printable_unicode_list(Term) -> boolean() when
+      Term :: term().
 
 printable_unicode_list([C|Cs]) when is_integer(C), C >= $\040, C =< $\176 ->
     printable_unicode_list(Cs);
diff --git a/lib/stdlib/src/io_lib_format.erl b/lib/stdlib/src/io_lib_format.erl
index 49a00a4ec7..5680f83ab6 100644
--- a/lib/stdlib/src/io_lib_format.erl
+++ b/lib/stdlib/src/io_lib_format.erl
@@ -1,7 +1,7 @@
 %%
 %% %CopyrightBegin%
 %% 
-%% Copyright Ericsson AB 1996-2011. All Rights Reserved.
+%% Copyright Ericsson AB 1996-2012. 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
@@ -22,7 +22,7 @@
 
 -export([fwrite/2,fwrite_g/1,indentation/2]).
 
-%% fwrite(Format, ArgList) -> [Char].
+%% fwrite(Format, ArgList) -> [unicode:unicode:char()].
 %%  Format the arguments in ArgList after string Format. Just generate
 %%  an error if there is an error in the arguments.
 %%
@@ -133,7 +133,7 @@ pcount([{$P,_As,_F,_Ad,_P,_Pad,_Enc}|Cs], Acc) -> pcount(Cs, Acc+1);
 pcount([_|Cs], Acc) -> pcount(Cs, Acc);
 pcount([], Acc) -> Acc.
 
-%% build([Control], Pc, Indentation) -> [Char].
+%% build([Control], Pc, Indentation) -> [unicode:unicode_char()].
 %%  Interpret the control structures. Count the number of print
 %%  remaining and only calculate indentation when necessary. Must also
 %%  be smart when calculating indentation for characters in format.
@@ -154,7 +154,7 @@ decr_pc($p, Pc) -> Pc - 1;
 decr_pc($P, Pc) -> Pc - 1;
 decr_pc(_, Pc) -> Pc.
 
-%% indentation([Char], Indentation) -> Indentation.
+%% indentation([unicode:unicode_char()], Indentation) -> Indentation.
 %%  Calculate the indentation of the end of a string given its start
 %%  indentation. We assume tabs at 8 cols.
 
@@ -167,19 +167,19 @@ indentation([C|Cs], I) ->
 indentation([], I) -> I.
 
 %% control(FormatChar, [Argument], FieldWidth, Adjust, Precision, PadChar,
-%%	   Indentation) ->
-%%	[Char]
+%%	   Encoding, Indentation) ->
+%%	[unicode:unicode_char()]
 %%  This is the main dispatch function for the various formatting commands.
 %%  Field widths and precisions have already been calculated.
 
 control($w, [A], F, Adj, P, Pad, _Enc,_I) ->
     term(io_lib:write(A, -1), F, Adj, P, Pad);
-control($p, [A], F, Adj, P, Pad, _Enc, I) ->
-    print(A, -1, F, Adj, P, Pad, I);
+control($p, [A], F, Adj, P, Pad, Enc, I) ->
+    print(A, -1, F, Adj, P, Pad, Enc, I);
 control($W, [A,Depth], F, Adj, P, Pad, _Enc, _I) when is_integer(Depth) ->
     term(io_lib:write(A, Depth), F, Adj, P, Pad);
-control($P, [A,Depth], F, Adj, P, Pad, _Enc, I) when is_integer(Depth) ->
-    print(A, Depth, F, Adj, P, Pad, I);
+control($P, [A,Depth], F, Adj, P, Pad, Enc, I) when is_integer(Depth) ->
+    print(A, Depth, F, Adj, P, Pad, Enc, I);
 control($s, [A], F, Adj, P, Pad, _Enc, _I) when is_atom(A) ->
     string(atom_to_list(A), F, Adj, P, Pad);
 control($s, [L0], F, Adj, P, Pad, latin1, _I) ->
@@ -187,6 +187,7 @@ control($s, [L0], F, Adj, P, Pad, latin1, _I) ->
     string(L, F, Adj, P, Pad);
 control($s, [L0], F, Adj, P, Pad, unicode, _I) ->
     L = unicode:characters_to_list(L0),
+    true = is_list(L),
     uniconv(string(L, F, Adj, P, Pad));
 control($e, [A], F, Adj, P, Pad, _Enc, _I) when is_float(A) ->
     fwrite_e(A, F, Adj, P, Pad);
@@ -256,13 +257,17 @@ term(T, F, Adj, P0, Pad) ->
 	    adjust(T, chars(Pad, F-L), Adj)
     end.
 
-%% print(Term, Depth, Field, Adjust, Precision, PadChar, Indentation)
+%% print(Term, Depth, Field, Adjust, Precision, PadChar, Encoding,
+%%       Indentation)
 %%  Print a term.
 
-print(T, D, none, Adj, P, Pad, I) -> print(T, D, 80, Adj, P, Pad, I);
-print(T, D, F, Adj, none, Pad, I) -> print(T, D, F, Adj, I+1, Pad, I);
-print(T, D, F, right, P, _Pad, _I) ->
-    io_lib_pretty:print(T, P, F, D).
+print(T, D, none, Adj, P, Pad, E, I) -> print(T, D, 80, Adj, P, Pad, E, I);
+print(T, D, F, Adj, none, Pad, E, I) -> print(T, D, F, Adj, I+1, Pad, E, I);
+print(T, D, F, right, P, _Pad, latin1, _I) ->
+    io_lib_pretty:print(T, P, F, D);
+print(T, D, F, right, P, _Pad, Enc, _I) ->
+    Options = [{column, P}, {line_length, F}, {depth, D}, {encoding, Enc}],
+    io_lib_pretty:print(T, Options).
 
 %% fwrite_e(Float, Field, Adjust, Precision, PadChar)
 
@@ -608,7 +613,7 @@ prefixed_integer(Int, F, Adj, Base, Pad, Prefix, Lowercase)
 	    term([Prefix|S], F, Adj, none, Pad)
     end.
 
-%% char(Char, Field, Adjust, Precision, PadChar) -> [Char].
+%% char(Char, Field, Adjust, Precision, PadChar) -> [unicode:unicode_char()].
 
 char(C, none, _Adj, none, _Pad) -> [C];
 char(C, F, _Adj, none, _Pad) -> chars(C, F);
diff --git a/lib/stdlib/src/io_lib_pretty.erl b/lib/stdlib/src/io_lib_pretty.erl
index 169410796b..99ad281a9b 100644
--- a/lib/stdlib/src/io_lib_pretty.erl
+++ b/lib/stdlib/src/io_lib_pretty.erl
@@ -1,7 +1,7 @@
 %%
 %% %CopyrightBegin%
 %% 
-%% Copyright Ericsson AB 1996-2009. All Rights Reserved.
+%% Copyright Ericsson AB 1996-2012. 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
@@ -33,43 +33,76 @@
 %% print(Term, Column, LineLength, Depth) -> [Chars]
 %% Depth = -1 gives unlimited print depth. Use io_lib:write for atomic terms.
 
+-spec print(term()) -> io_lib:chars().
+
 print(Term) ->
     print(Term, 1, 80, -1).
 
 %% print(Term, RecDefFun) -> [Chars]
 %% print(Term, Depth, RecDefFun) -> [Chars]
 %% RecDefFun = fun(Tag, NoFields) -> [FieldTag] | no
-%% Used by the shell for printing records.
+%% Used by the shell for printing records and for Unicode.
+
+-type rec_print_fun() :: fun((Tag :: atom(), NFields :: non_neg_integer()) ->
+                                  no | [FieldName :: atom()]).
+-type column() :: integer().
+-type line_length() :: pos_integer().
+-type depth() :: integer().
+-type max_chars() :: integer().
+
+-type chars() :: io_lib:chars().
+-type unicode_chars() :: io_lib:unicode_chars().
+-type option() :: {column, column()}
+                | {line_length, line_length()}
+                | {depth, depth()}
+                | {max_chars, max_chars()}
+                | {record_print_fun, rec_print_fun()}
+                | {encoding, latin1 | utf8 | unicode}.
+-type options() :: [option()].
+
+-spec print(term(), rec_print_fun()) -> chars() | unicode_chars();
+           (term(), options()) -> chars() | unicode_chars().
+
+print(Term, Options) when is_list(Options) ->
+    Col = proplists:get_value(column, Options, 1),
+    Ll = proplists:get_value(line_length, Options, 80),
+    D = proplists:get_value(depth, Options, -1),
+    M = proplists:get_value(max_chars, Options, -1),
+    RecDefFun = proplists:get_value(record_print_fun, Options, no_fun),
+    Encoding = proplists:get_value(encoding, Options, epp:default_encoding()),
+    print(Term, Col, Ll, D, M, RecDefFun, Encoding);
 print(Term, RecDefFun) ->
     print(Term, -1, RecDefFun).
 
+-spec print(term(), depth(), rec_print_fun()) -> chars() | unicode_chars().
+
 print(Term, Depth, RecDefFun) ->
     print(Term, 1, 80, Depth, RecDefFun).
 
+-spec print(term(), column(), line_length(), depth()) ->
+                   chars() | unicode_chars().
+
 print(Term, Col, Ll, D) ->
-    print(Term, Col, Ll, D, _M=-1, no_fun).
+    print(Term, Col, Ll, D, _M=-1, no_fun, latin1).
 
+-spec print(term(), column(), line_length(), depth(), rec_print_fun()) ->
+                   chars() | unicode_chars().
 print(Term, Col, Ll, D, RecDefFun) ->
     print(Term, Col, Ll, D, _M=-1, RecDefFun).
 
-print(_, _, _, 0, _M, _RF) -> "...";
-print(Term, Col, Ll, D, M, RecDefFun) when Col =< 0 ->
-    print(Term, 1, Ll, D, M, RecDefFun);
-print(Term, Col, Ll, D, M0, RecDefFun) when is_tuple(Term); 
-                                            is_list(Term) ->
-    If = {_S, Len} = print_length(Term, D, RecDefFun),
-    M = max_cs(M0, Len),
-    if
-        Len < Ll - Col, Len =< M ->
-            write(If);
-        true ->
-            TInd = while_fail([-1, 4], 
-                              fun(I) -> cind(If, Col, Ll, M, I, 0, 0) end, 
-                              1),
-            pp(If, Col, Ll, M, TInd, indent(Col), 0, 0)
-    end;
-print(<<_/bitstring>>=Term, Col, Ll, D, M0, RecDefFun) ->
-    If = {_S, Len} = print_length(Term, D, RecDefFun),
+-spec print(term(), column(), line_length(), depth(), max_chars(),
+            rec_print_fun()) -> chars() | unicode_chars().
+
+print(Term, Col, Ll, D, M, RecDefFun) ->
+    print(Term, Col, Ll, D, M, RecDefFun, latin1).
+
+print(_, _, _, 0, _M, _RF, _Enc) -> "...";
+print(Term, Col, Ll, D, M, RecDefFun, Enc) when Col =< 0 ->
+    print(Term, 1, Ll, D, M, RecDefFun, Enc);
+print(Term, Col, Ll, D, M0, RecDefFun, Enc) when is_tuple(Term);
+                                                 is_list(Term);
+                                                 is_bitstring(Term) ->
+    If = {_S, Len} = print_length(Term, D, RecDefFun, Enc),
     M = max_cs(M0, Len),
     if
         Len < Ll - Col, Len =< M ->
@@ -80,7 +113,7 @@ print(<<_/bitstring>>=Term, Col, Ll, D, M0, RecDefFun) ->
                               1),
             pp(If, Col, Ll, M, TInd, indent(Col), 0, 0)
     end;
-print(Term, _Col, _Ll, _D, _M, _RF) ->
+print(Term, _Col, _Ll, _D, _M, _RF, _Enc) ->
     io_lib:write(Term).
 
 %%%
@@ -294,50 +327,56 @@ write_tail(E, S) ->
 %% counted but need to be added later.
 
 %% D =/= 0
-print_length([], _D, _RF) ->
+print_length([], _D, _RF, _Enc) ->
     {"[]", 2};
-print_length({}, _D, _RF) ->
+print_length({}, _D, _RF, _Enc) ->
     {"{}", 2};
-print_length(List, D, RF) when is_list(List) ->
-    case printable_list(List, D) of
+print_length(List, D, RF, Enc) when is_list(List) ->
+    case printable_list(List, D, Enc) of
         true ->
-            S = io_lib:write_string(List, $"), %"
+            S = write_string(List, Enc),
             {S, length(S)};
         %% Truncated lists could break some existing code.
         % {true, Prefix} ->
-        %    S = io_lib:write_string(Prefix, $"), %"
+        %    S = write_string(Prefix, Enc),
         %    {[S | "..."], 3 + length(S)};
         false ->
-            print_length_list(List, D, RF)
+            print_length_list(List, D, RF, Enc)
     end;
-print_length(Fun, _D, _RF) when is_function(Fun) ->
+print_length(Fun, _D, _RF, _Enc) when is_function(Fun) ->
     S = io_lib:write(Fun),
     {S, iolist_size(S)};
-print_length(R, D, RF) when is_atom(element(1, R)), 
-                            is_function(RF) ->
+print_length(R, D, RF, Enc) when is_atom(element(1, R)),
+                                 is_function(RF) ->
     case RF(element(1, R), tuple_size(R) - 1) of
         no -> 
-            print_length_tuple(R, D, RF);
+            print_length_tuple(R, D, RF, Enc);
         RDefs ->
-            print_length_record(R, D, RF, RDefs)
+            print_length_record(R, D, RF, RDefs, Enc)
     end;
-print_length(Tuple, D, RF) when is_tuple(Tuple) ->
-    print_length_tuple(Tuple, D, RF);
-print_length(<<>>, _D, _RF) ->
+print_length(Tuple, D, RF, Enc) when is_tuple(Tuple) ->
+    print_length_tuple(Tuple, D, RF, Enc);
+print_length(<<>>, _D, _RF, _Enc) ->
     {"<<>>", 4};
-print_length(<<_/bitstring>>, 1, _RF) ->
+print_length(<<_/bitstring>>, 1, _RF, _Enc) ->
     {"<<...>>", 7};
-print_length(<<_/bitstring>>=Bin, D, _RF) ->
+print_length(<<_/bitstring>>=Bin, D, _RF, Enc) ->
     case bit_size(Bin) rem 8 of
         0 ->
 	    D1 = D - 1, 
-	    case printable_bin(Bin, D1) of
-	        List when is_list(List) ->
-                    S = io_lib:write_string(List, $"),
+	    case printable_bin(Bin, D1, Enc) of
+                {true, List} when is_list(List) ->
+                    S = io_lib:write_string(List, $"), %"
 	            {[$<,$<,S,$>,$>], 4 + length(S)};
-	        {true, Prefix} -> 
-	            S = io_lib:write_string(Prefix, $"), 
-	            {[$<,$<, S | "...>>"], 4 + length(S)};
+                {false, List} when is_list(List) ->
+                    S = io_lib:write_unicode_string(List, $"), %"
+	            {[$<,$<,S,"/utf8>>"], 9 + length(S)};
+	        {true, true, Prefix} ->
+	            S = io_lib:write_string(Prefix, $"), %"
+	            {[$<,$<, S | "...>>"], 7 + length(S)};
+	        {false, true, Prefix} ->
+                    S = io_lib:write_unicode_string(Prefix, $"), %"
+	            {[$<,$<, S | "/utf8...>>"], 12 + length(S)};
 	        false ->
 	            S = io_lib:write(Bin, D),
 	            {{bin,S}, iolist_size(S)}
@@ -346,51 +385,51 @@ print_length(<<_/bitstring>>=Bin, D, _RF) ->
            S = io_lib:write(Bin, D),
 	   {{bin,S}, iolist_size(S)}
     end;    
-print_length(Term, _D, _RF) ->
+print_length(Term, _D, _RF, _Enc) ->
     S = io_lib:write(Term),
     {S, iolist_size(S)}.
 
-print_length_tuple(_Tuple, 1, _RF) ->
+print_length_tuple(_Tuple, 1, _RF, _Enc) ->
     {"{...}", 5};
-print_length_tuple(Tuple, D, RF) ->
-    L = print_length_list1(tuple_to_list(Tuple), D, RF),
+print_length_tuple(Tuple, D, RF, Enc) ->
+    L = print_length_list1(tuple_to_list(Tuple), D, RF, Enc),
     IsTagged = is_atom(element(1, Tuple)) and (tuple_size(Tuple) > 1),
     {{tuple,IsTagged,L}, list_length(L, 2)}.
 
-print_length_record(_Tuple, 1, _RF, _RDefs) ->
+print_length_record(_Tuple, 1, _RF, _RDefs, _Enc) ->
     {"{...}", 5};
-print_length_record(Tuple, D, RF, RDefs) ->
+print_length_record(Tuple, D, RF, RDefs, Enc) ->
     Name = [$# | io_lib:write_atom(element(1, Tuple))],
     NameL = length(Name),
-    L = print_length_fields(RDefs, D - 1, tl(tuple_to_list(Tuple)), RF),
+    L = print_length_fields(RDefs, D - 1, tl(tuple_to_list(Tuple)), RF, Enc),
     {{record, [{Name,NameL} | L]}, list_length(L, NameL + 2)}.
 
-print_length_fields([], _D, [], _RF) ->
+print_length_fields([], _D, [], _RF, _Enc) ->
     [];
-print_length_fields(_, 1, _, _RF) -> 
+print_length_fields(_, 1, _, _RF, _Enc) ->
     {dots, 3};
-print_length_fields([Def | Defs], D, [E | Es], RF) ->
-    [print_length_field(Def, D - 1, E, RF) | 
-     print_length_fields(Defs, D - 1, Es, RF)].
+print_length_fields([Def | Defs], D, [E | Es], RF, Enc) ->
+    [print_length_field(Def, D - 1, E, RF, Enc) |
+     print_length_fields(Defs, D - 1, Es, RF, Enc)].
 
-print_length_field(Def, D, E, RF) ->
+print_length_field(Def, D, E, RF, Enc) ->
     Name = io_lib:write_atom(Def),
-    {S, L} = print_length(E, D, RF),
+    {S, L} = print_length(E, D, RF, Enc),
     NameL = length(Name) + 3,
     {{field, Name, NameL, {S, L}}, NameL + L}.
 
-print_length_list(List, D, RF) -> 
-    L = print_length_list1(List, D, RF),
+print_length_list(List, D, RF, Enc) ->
+    L = print_length_list1(List, D, RF, Enc),
     {{list, L}, list_length(L, 2)}.
 
-print_length_list1([], _D, _RF) ->
+print_length_list1([], _D, _RF, _Enc) ->
     [];
-print_length_list1(_, 1, _RF) ->
+print_length_list1(_, 1, _RF, _Enc) ->
     {dots, 3};
-print_length_list1([E | Es], D, RF) ->
-    [print_length(E, D - 1, RF) | print_length_list1(Es, D - 1, RF)];
-print_length_list1(E, D, RF) ->
-    print_length(E, D - 1, RF).
+print_length_list1([E | Es], D, RF, Enc) ->
+    [print_length(E, D - 1, RF, Enc) | print_length_list1(Es, D - 1, RF, Enc)];
+print_length_list1(E, D, RF, Enc) ->
+    print_length(E, D - 1, RF, Enc).
 
 list_length([], Acc) ->
     Acc;
@@ -409,16 +448,16 @@ list_length_tail({_, Len}, Acc) ->
 %% ?CHARS printable characters has depth 1.
 -define(CHARS, 4).
 
-printable_list(L, D) when D < 0 ->
-    io_lib:printable_list(L);
-printable_list(_L, 1) ->
+printable_list(_L, 1, _Enc) ->
     false;
-printable_list(L, _D) ->
-    io_lib:printable_list(L).
+printable_list(L, _D, latin1) ->
+    io_lib:printable_list(L);
+printable_list(L, _D, _Uni) ->
+    io_lib:printable_unicode_list(L).
 %% Truncated lists could break some existing code.
-% printable_list(L, D) ->
+% printable_list(L, D, Enc) when D >= 0 ->
 %     Len = ?CHARS * (D - 1),
-%     case printable_list1(L, Len) of
+%     case printable_list1(L, Len, Enc) of
 %         all ->
 %             true;
 %         N when is_integer(N), Len - N >= D - 1 ->
@@ -428,32 +467,41 @@ printable_list(L, _D) ->
 %             false
 %     end.
 
-printable_bin(Bin, D) when D >= 0, ?CHARS * D =< byte_size(Bin) ->
-    printable_bin(Bin, erlang:min(?CHARS * D, byte_size(Bin)), D);
-printable_bin(Bin, D) ->
-    printable_bin(Bin, byte_size(Bin), D).
+printable_bin(Bin, D, Enc) when D >= 0, ?CHARS * D =< byte_size(Bin) ->
+    printable_bin(Bin, erlang:min(?CHARS * D, byte_size(Bin)), D, Enc);
+printable_bin(Bin, D, Enc) ->
+    printable_bin(Bin, byte_size(Bin), D, Enc).
 
-printable_bin(Bin, Len, D) ->
+printable_bin(Bin, Len, D, latin1) ->
     N = erlang:min(20, Len),
     L = binary_to_list(Bin, 1, N),
     case printable_list1(L, N) of
         all when N =:= byte_size(Bin)  ->
-            L;
-        all when N =:= Len -> % N < byte_size(Bin)
             {true, L};
+        all when N =:= Len -> % N < byte_size(Bin)
+            {true, true, L};
         all ->
             case printable_bin1(Bin, 1 + N, Len - N) of
                 0 when byte_size(Bin) =:= Len ->
-                    binary_to_list(Bin);
+                    {true, binary_to_list(Bin)};
                 NC when D > 0, Len - NC >= D ->
-                    {true, binary_to_list(Bin, 1, Len - NC)};
+                    {true, true, binary_to_list(Bin, 1, Len - NC)};
                 NC when is_integer(NC) ->
                     false
             end;
         NC when is_integer(NC), D > 0, N - NC >= D ->
-            {true, binary_to_list(Bin, 1, N - NC)};
+            {true, true, binary_to_list(Bin, 1, N - NC)};
         NC when is_integer(NC) ->
             false
+    end;
+printable_bin(Bin, Len, D, _Uni) ->
+    case printable_unicode(Bin, Len, []) of
+        {_, <<>>, L} ->
+            {byte_size(Bin) =:= length(L), L};
+        {NC, Bin1, L} when D > 0, Len - NC >= D ->
+            {byte_size(Bin)-byte_size(Bin1) =:= length(L), true, L};
+        {_NC, _Bin, _L} ->
+            false
     end.
 
 printable_bin1(_Bin, _Start, 0) ->
@@ -484,6 +532,16 @@ printable_list1([$\e | Cs], N) -> printable_list1(Cs, N - 1);
 printable_list1([], _) -> all;
 printable_list1(_, N) -> N.
 
+printable_unicode(<<C/utf8, R/binary>>, I, L) when I > 0 ->
+    printable_unicode(R, I - 1, [C | L]);
+printable_unicode(Bin, I, L) ->
+    {I, Bin, lists:reverse(L)}.
+
+write_string(S, latin1) ->
+    io_lib:write_string(S, $"); %"
+write_string(S, _Uni) ->
+    io_lib:write_unicode_string(S, $"). %"
+
 %% Throw 'no_good' if the indentation exceeds half the line length
 %% unless there is room for M characters on the line.
 
diff --git a/lib/stdlib/src/lib.erl b/lib/stdlib/src/lib.erl
index cf4b87d7eb..b2ce2a5a8f 100644
--- a/lib/stdlib/src/lib.erl
+++ b/lib/stdlib/src/lib.erl
@@ -21,8 +21,9 @@
 -export([flush_receive/0, error_message/2, progname/0, nonl/1, send/2,
 	 sendw/2, eval_str/1]).
 
--export([format_exception/6, format_stacktrace/4, 
-         format_call/4, format_fun/1]).
+-export([format_exception/6, format_exception/7,
+         format_stacktrace/4, format_stacktrace/5,
+         format_call/4, format_call/5, format_fun/1]).
 
 -spec flush_receive() -> 'ok'.
 
@@ -128,32 +129,49 @@ all_white(_)       -> false.
 %%   as indentation whenever newline has been inserted);
 %% Class, Reason and StackTrace are the exception;
 %% FormatFun = fun(Term, I) -> iolist() formats terms;
-%% StackFun = fun(Mod, Fun, Arity) -> bool() is used for trimming the
+%% StackFun = fun(Mod, Fun, Arity) -> boolean() is used for trimming the
 %%   end of the stack (typically calls to erl_eval are skipped).
-format_exception(I, Class, Reason, StackTrace, StackFun, FormatFun) 
+format_exception(I, Class, Reason, StackTrace, StackFun, FormatFun) ->
+    format_exception(I, Class, Reason, StackTrace, StackFun, FormatFun,
+                     latin1).
+
+%% -> iolist() | unicode:charlist() (no \n at end)
+%% FormatFun = fun(Term, I) -> iolist() | unicode:charlist().
+format_exception(I, Class, Reason, StackTrace, StackFun, FormatFun, Encoding)
             when is_integer(I), I >= 1, is_function(StackFun, 3), 
                  is_function(FormatFun, 2) ->
     S = n_spaces(I-1),
     {Term,Trace1,Trace} = analyze_exception(Class, Reason, StackTrace),
-    Expl0 = explain_reason(Term, Class, Trace1, FormatFun, S),
-    Expl = io_lib:fwrite(<<"~s~s">>, [exited(Class), Expl0]),
-    case format_stacktrace1(S, Trace, FormatFun, StackFun) of
+    Expl0 = explain_reason(Term, Class, Trace1, FormatFun, S, Encoding),
+    FormatString = case Encoding of
+                       latin1 -> "~s~s";
+                       _ -> "~s~ts"
+                   end,
+    Expl = io_lib:fwrite(FormatString, [exited(Class), Expl0]),
+    case format_stacktrace1(S, Trace, FormatFun, StackFun, Encoding) of
         [] -> Expl;
         Stack -> [Expl, $\n, Stack]
     end.
 
 %% -> iolist() (no \n at end)
-format_stacktrace(I, StackTrace, StackFun, FormatFun) 
+format_stacktrace(I, StackTrace, StackFun, FormatFun) ->
+    format_stacktrace(I, StackTrace, StackFun, FormatFun, latin1).
+
+%% -> iolist() | unicode:charlist()  (no \n at end)
+format_stacktrace(I, StackTrace, StackFun, FormatFun, Encoding)
             when is_integer(I), I >= 1, is_function(StackFun, 3), 
                  is_function(FormatFun, 2) ->
     S = n_spaces(I-1),
-    format_stacktrace1(S, StackTrace, FormatFun, StackFun).
+    format_stacktrace1(S, StackTrace, FormatFun, StackFun, Encoding).
 
 %% -> iolist() (no \n at end)
-format_call(I, ForMForFun, As, FormatFun) when is_integer(I), I >= 1,
-                                               is_list(As),
-                                               is_function(FormatFun, 2) ->
-    format_call("", n_spaces(I-1), ForMForFun, As, FormatFun).
+format_call(I, ForMForFun, As, FormatFun) ->
+    format_call(I, ForMForFun, As, FormatFun, latin1).
+
+%% -> iolist() | unicode:charlist()  (no \n at end)
+format_call(I, ForMForFun, As, FormatFun, Enc)
+       when is_integer(I), I >= 1, is_list(As), is_function(FormatFun, 2) ->
+    format_call("", n_spaces(I-1), ForMForFun, As, FormatFun, Enc).
 
 %% -> iolist() (no \n at end)
 format_fun(Fun) when is_function(Fun) ->
@@ -204,79 +222,80 @@ is_stacktrace(_) ->
     false.
 
 %% ERTS exit codes (some of them are also returned by erl_eval):
-explain_reason(badarg, error, [], _PF, _S) ->
+explain_reason(badarg, error, [], _PF, _S, _Enc) ->
     <<"bad argument">>;
-explain_reason({badarg,V}, error=Cl, [], PF, S) -> % orelse, andalso
+explain_reason({badarg,V}, error=Cl, [], PF, S, _Enc) -> % orelse, andalso
     format_value(V, <<"bad argument: ">>, Cl, PF, S);
-explain_reason(badarith, error, [], _PF, _S) ->
+explain_reason(badarith, error, [], _PF, _S, _Enc) ->
     <<"an error occurred when evaluating an arithmetic expression">>;
-explain_reason({badarity,{Fun,As}}, error, [], _PF, _S) 
+explain_reason({badarity,{Fun,As}}, error, [], _PF, _S, _Enc)
                                       when is_function(Fun) ->
     %% Only the arity is displayed, not the arguments As.
     io_lib:fwrite(<<"~s called with ~s">>, 
                   [format_fun(Fun), argss(length(As))]);
-explain_reason({badfun,Term}, error=Cl, [], PF, S) ->
+explain_reason({badfun,Term}, error=Cl, [], PF, S, _Enc) ->
     format_value(Term, <<"bad function ">>, Cl, PF, S);
-explain_reason({badmatch,Term}, error=Cl, [], PF, S) ->
-    format_value(Term, <<"no match of right hand side value ">>, Cl, PF, S);
-explain_reason({case_clause,V}, error=Cl, [], PF, S) ->
+explain_reason({badmatch,Term}, error=Cl, [], PF, S, _Enc) ->
+    Str = <<"no match of right hand side value ">>,
+    format_value(Term, Str, Cl, PF, S);
+explain_reason({case_clause,V}, error=Cl, [], PF, S, _Enc) ->
     %% "there is no case clause with a true guard sequence and a
     %% pattern matching..."
     format_value(V, <<"no case clause matching ">>, Cl, PF, S);
-explain_reason(function_clause, error, [{F,A}], _PF, _S) ->
+explain_reason(function_clause, error, [{F,A}], _PF, _S, _Enc) ->
     %% Shell commands
     FAs = io_lib:fwrite(<<"~w/~w">>, [F, A]),
     [<<"no function clause matching call to ">> | FAs];
-explain_reason(function_clause, error=Cl, [{M,F,As,Loc}], PF, S) ->
+explain_reason(function_clause, error=Cl, [{M,F,As,Loc}], PF, S, Enc) ->
     Str = <<"no function clause matching ">>,
-    [format_errstr_call(Str, Cl, {M,F}, As, PF, S),$\s|location(Loc)];
-explain_reason(if_clause, error, [], _PF, _S) ->
+    [format_errstr_call(Str, Cl, {M,F}, As, PF, S, Enc),$\s|location(Loc)];
+explain_reason(if_clause, error, [], _PF, _S, _Enc) ->
     <<"no true branch found when evaluating an if expression">>;
-explain_reason(noproc, error, [], _PF, _S) ->
+explain_reason(noproc, error, [], _PF, _S, _Enc) ->
     <<"no such process or port">>;
-explain_reason(notalive, error, [], _PF, _S) ->
+explain_reason(notalive, error, [], _PF, _S, _Enc) ->
     <<"the node cannot be part of a distributed system">>;
-explain_reason(system_limit, error, [], _PF, _S) ->
+explain_reason(system_limit, error, [], _PF, _S, _Enc) ->
     <<"a system limit has been reached">>;
-explain_reason(timeout_value, error, [], _PF, _S) ->
+explain_reason(timeout_value, error, [], _PF, _S, _Enc) ->
     <<"bad receive timeout value">>;
-explain_reason({try_clause,V}, error=Cl, [], PF, S) ->
+explain_reason({try_clause,V}, error=Cl, [], PF, S, _Enc) ->
     %% "there is no try clause with a true guard sequence and a
     %% pattern matching..."
     format_value(V, <<"no try clause matching ">>, Cl, PF, S);
-explain_reason(undef, error, [{M,F,A,_}], _PF, _S) ->
+explain_reason(undef, error, [{M,F,A,_}], _PF, _S, _Enc) ->
     %% Only the arity is displayed, not the arguments, if there are any.
     io_lib:fwrite(<<"undefined function ~s">>, 
                   [mfa_to_string(M, F, n_args(A))]);
-explain_reason({shell_undef,F,A,_}, error, [], _PF, _S) ->
+explain_reason({shell_undef,F,A,_}, error, [], _PF, _S, _Enc) ->
     %% Give nicer reports for undefined shell functions
     %% (but not when the user actively calls shell_default:F(...)).
     io_lib:fwrite(<<"undefined shell command ~s/~w">>, [F, n_args(A)]);
 %% Exit codes returned by erl_eval only:
-explain_reason({argument_limit,_Fun}, error, [], _PF, _S) ->
+explain_reason({argument_limit,_Fun}, error, [], _PF, _S, _Enc) ->
     io_lib:fwrite(<<"limit of number of arguments to interpreted function"
                     " exceeded">>, []);
-explain_reason({bad_filter,V}, error=Cl, [], PF, S) ->
+explain_reason({bad_filter,V}, error=Cl, [], PF, S, _Enc) ->
     format_value(V, <<"bad filter ">>, Cl, PF, S);
-explain_reason({bad_generator,V}, error=Cl, [], PF, S) ->
+explain_reason({bad_generator,V}, error=Cl, [], PF, S, _Enc) ->
     format_value(V, <<"bad generator ">>, Cl, PF, S);
-explain_reason({unbound,V}, error, [], _PF, _S) ->
+explain_reason({unbound,V}, error, [], _PF, _S, _Enc) ->
     io_lib:fwrite(<<"variable ~w is unbound">>, [V]);
 %% Exit codes local to the shell module (restricted shell):
-explain_reason({restricted_shell_bad_return, V}, exit=Cl, [], PF, S) ->
+explain_reason({restricted_shell_bad_return, V}, exit=Cl, [], PF, S, _Enc) ->
     Str = <<"restricted shell module returned bad value ">>,
     format_value(V, Str, Cl, PF, S);
 explain_reason({restricted_shell_disallowed,{ForMF,As}}, 
-               exit=Cl, [], PF, S) ->
+               exit=Cl, [], PF, S, Enc) ->
     %% ForMF can be a fun, but not a shell fun.
     Str = <<"restricted shell does not allow ">>,
-    format_errstr_call(Str, Cl, ForMF, As, PF, S);
-explain_reason(restricted_shell_started, exit, [], _PF, _S) ->
+    format_errstr_call(Str, Cl, ForMF, As, PF, S, Enc);
+explain_reason(restricted_shell_started, exit, [], _PF, _S, _Enc) ->
     <<"restricted shell starts now">>;
-explain_reason(restricted_shell_stopped, exit, [], _PF, _S) ->
+explain_reason(restricted_shell_stopped, exit, [], _PF, _S, _Enc) ->
     <<"restricted shell stopped">>;
 %% Other exit code:
-explain_reason(Reason, Class, [], PF, S) ->
+explain_reason(Reason, Class, [], PF, S, _Enc) ->
     PF(Reason, (iolist_size(S)+1) + exited_size(Class)).
 
 n_args(A) when is_integer(A) ->
@@ -293,28 +312,28 @@ argss(2) ->
 argss(I) ->
     io_lib:fwrite(<<"~w arguments">>, [I]).
 
-format_stacktrace1(S0, Stack0, PF, SF) ->
+format_stacktrace1(S0, Stack0, PF, SF, Enc) ->
     Stack1 = lists:dropwhile(fun({M,F,A,_}) -> SF(M, F, A)
                              end, lists:reverse(Stack0)),
     S = ["  " | S0],
     Stack = lists:reverse(Stack1),
-    format_stacktrace2(S, Stack, 1, PF).
+    format_stacktrace2(S, Stack, 1, PF, Enc).
 
-format_stacktrace2(S, [{M,F,A,L}|Fs], N, PF) when is_integer(A) ->
+format_stacktrace2(S, [{M,F,A,L}|Fs], N, PF, Enc) when is_integer(A) ->
     [io_lib:fwrite(<<"~s~s ~s ~s">>,
                    [sep(N, S), origin(N, M, F, A),
 		    mfa_to_string(M, F, A),
 		    location(L)])
-     | format_stacktrace2(S, Fs, N + 1, PF)];
-format_stacktrace2(S, [{M,F,As,_}|Fs], N, PF) when is_list(As) ->
+     | format_stacktrace2(S, Fs, N + 1, PF, Enc)];
+format_stacktrace2(S, [{M,F,As,_}|Fs], N, PF, Enc) when is_list(As) ->
     A = length(As),
     CalledAs = [S,<<"   called as ">>],
-    C = format_call("", CalledAs, {M,F}, As, PF),
-    [io_lib:fwrite(<<"~s~s ~s\n~s~s">>,
+    C = format_call("", CalledAs, {M,F}, As, PF, Enc),
+    [io_lib:fwrite(<<"~s~s ~s\n~s~ts">>,
 		   [sep(N, S), origin(N, M, F, A), mfa_to_string(M, F, A),
                     CalledAs, C])
-     | format_stacktrace2(S, Fs, N + 1, PF)];
-format_stacktrace2(_S, [], _N, _PF) ->
+     | format_stacktrace2(S, Fs, N + 1, PF, Enc)];
+format_stacktrace2(_S, [], _N, _PF, _Enc) ->
     "".
 
 location(L) ->
@@ -338,22 +357,22 @@ origin(1, M, F, A) ->
 origin(_N, _M, _F, _A) ->
     <<"in call from">>.
 
-format_errstr_call(ErrStr, Class, ForMForFun, As, PF, Pre0) ->
+format_errstr_call(ErrStr, Class, ForMForFun, As, PF, Pre0, Enc) ->
     Pre1 = [Pre0 | n_spaces(exited_size(Class))],
-    format_call(ErrStr, Pre1, ForMForFun, As, PF).
+    format_call(ErrStr, Pre1, ForMForFun, As, PF, Enc).
 
-format_call(ErrStr, Pre1, ForMForFun, As, PF) ->
+format_call(ErrStr, Pre1, ForMForFun, As, PF, Enc) ->
     Arity = length(As),
     [ErrStr |
      case is_op(ForMForFun, Arity) of
          {yes,Op} -> 
-             format_op(ErrStr, Pre1, Op, As, PF);
+             format_op(ErrStr, Pre1, Op, As, PF, Enc);
          no ->
              MFs = mf_to_string(ForMForFun, Arity),
              I1 = iolist_size([Pre1,ErrStr|MFs]),
-             S1 = pp_arguments(PF, As, I1),
-             S2 = pp_arguments(PF, As, iolist_size([Pre1|MFs])),
-             Long = count_nl(pp_arguments(PF, [a2345,b2345], I1)) > 0,
+             S1 = pp_arguments(PF, As, I1, Enc),
+             S2 = pp_arguments(PF, As, iolist_size([Pre1|MFs]), Enc),
+             Long = count_nl(pp_arguments(PF, [a2345,b2345], I1, Enc)) > 0,
              case Long or (count_nl(S2) < count_nl(S1)) of
                  true ->
                      [$\n, Pre1, MFs, S2];
@@ -362,11 +381,11 @@ format_call(ErrStr, Pre1, ForMForFun, As, PF) ->
              end
     end].
 
-format_op(ErrStr, Pre, Op, [A1], PF) ->
+format_op(ErrStr, Pre, Op, [A1], PF, _Enc) ->
     OpS = io_lib:fwrite(<<"~s ">>, [Op]),
     I1 = iolist_size([ErrStr,Pre,OpS]),
     [OpS | PF(A1, I1+1)];
-format_op(ErrStr, Pre, Op, [A1, A2], PF) ->
+format_op(ErrStr, Pre, Op, [A1, A2], PF, Enc) ->
     I1 = iolist_size([ErrStr,Pre]),
     S1 = PF(A1, I1+1),
     S2 = PF(A2, I1+1),
@@ -377,33 +396,40 @@ format_op(ErrStr, Pre, Op, [A1, A2], PF) ->
             [S1,Pre1,OpS,Pre1|S2];
         false ->
             OpS2 = io_lib:fwrite(<<" ~s ">>, [Op]),
-            S2_2 = PF(A2, iolist_size([ErrStr,Pre,S1|OpS2])+1),
+            Size1 = iolist_size([ErrStr,Pre|OpS2]),
+            {Size2,S1_2} = size(Enc, S1),
+            S2_2 = PF(A2, Size1+Size2+1),
             case count_nl(S2) < count_nl(S2_2) of
                 true ->
-                    [S1,Pre1,OpS,Pre1|S2];
+                    [S1_2,Pre1,OpS,Pre1|S2];
                 false ->
-                    [S1,OpS2|S2_2]
+                    [S1_2,OpS2|S2_2]
             end
     end.
 
-pp_arguments(PF, As, I) ->
-    case {As, io_lib:printable_list(As)} of
+pp_arguments(PF, As, I, Enc) ->
+    case {As, printable_list(Enc, As)} of
         {[Int | T], true} ->
             L = integer_to_list(Int),
             Ll = length(L),
             A = list_to_atom(lists:duplicate(Ll, $a)),
-            S0 = binary_to_list(iolist_to_binary(PF([A | T], I+1))),
-            brackets_to_parens([$[,L,string:sub_string(S0, 2+Ll)]);
+            S0 = unicode:characters_to_list(PF([A | T], I+1), Enc),
+            brackets_to_parens([$[,L,string:sub_string(S0, 2+Ll)], Enc);
         _ -> 
-            brackets_to_parens(PF(As, I+1))
+            brackets_to_parens(PF(As, I+1), Enc)
     end.
 
-brackets_to_parens(S) ->
-    B = iolist_to_binary(S),
+brackets_to_parens(S, Enc) ->
+    B = unicode:characters_to_binary(S, Enc),
     Sz = byte_size(B) - 2,
     <<$[,R:Sz/binary,$]>> = B,
     [$(,R,$)].
 
+printable_list(latin1, As) ->
+    io_lib:printable_list(As);
+printable_list(_, As) ->
+    io_lib:printable_unicode_list(As).
+
 mfa_to_string(M, F, A) ->
     io_lib:fwrite(<<"~s/~w">>, [mf_to_string({M, F}, A), A]).
 
@@ -472,3 +498,10 @@ exited(exit) ->
     <<"exception exit: ">>;
 exited(throw) ->
     <<"exception throw: ">>.
+
+size(latin1, S) ->
+    {iolist_size(S),S};
+size(_, S0) ->
+    S = unicode:characters_to_list(S0, unicode),
+    true = is_list(S),
+    {length(S),S}.
diff --git a/lib/stdlib/src/shell.erl b/lib/stdlib/src/shell.erl
index dc450f0ee6..424650b8b3 100644
--- a/lib/stdlib/src/shell.erl
+++ b/lib/stdlib/src/shell.erl
@@ -1,7 +1,7 @@
 %%
 %% %CopyrightBegin%
 %%
-%% Copyright Ericsson AB 1996-2011. All Rights Reserved.
+%% Copyright Ericsson AB 1996-2012. 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
@@ -128,7 +128,7 @@ start_restricted(RShMod) when is_atom(RShMod) ->
 	    error_logger:error_report(
 	      lists:flatten(
 		io_lib:fwrite(
-		  <<"Restricted shell module ~w not found: ~p\n">>, 
+		  "Restricted shell module ~w not found: ~"++cs_p() ++"\n",
 		  [RShMod,What]))),
 	    Error
     end.
@@ -192,7 +192,6 @@ server(StartSync) ->
 				 end,
 				 Bs0, default_packages()),
 		     default_modules()),
-    %% io:fwrite("Imported modules: ~p.\n", [erl_eval:bindings(Bs)]),
 
     %% Use an Ets table for record definitions. It takes too long to
     %% send a huge term to and from the evaluator. Ets makes it
@@ -230,9 +229,10 @@ server(StartSync) ->
             ok;
 	{RShMod2,What2} -> 
             io:fwrite(
-              <<"Warning! Restricted shell module ~w not found: ~p.\n"
-                "Only the commands q() and init:stop() will be allowed!\n">>,
-                      [RShMod2,What2]),
+              ("Warning! Restricted shell module ~w not found: ~"
+               ++cs_p()++".\n"
+               "Only the commands q() and init:stop() will be allowed!\n"),
+              [RShMod2,What2]),
             application:set_env(stdlib, restricted_shell, ?MODULE)
     end,
 
@@ -263,11 +263,11 @@ server_loop(N0, Eval_0, Bs00, RT, Ds00, History0, Results0) ->
                     end,
                     server_loop(N, Eval, Bs, RT, Ds, History, Results);
                 {error,E} ->
-                    fwrite_severity(benign, <<"~s">>, [E]),
+                    fwrite_severity(benign, <<"~ts">>, [E]),
                     server_loop(N0, Eval0, Bs0, RT, Ds0, History0, Results0)
             end;
 	{error,{Line,Mod,What},_EndLine} ->
-            fwrite_severity(benign, <<"~w: ~s">>, 
+            fwrite_severity(benign, <<"~w: ~ts">>,
                             [Line, Mod:format_error(What)]),
 	    server_loop(N0, Eval0, Bs0, RT, Ds0, History0, Results0);
 	{error,terminated} ->			%Io process terminated
@@ -277,7 +277,7 @@ server_loop(N0, Eval_0, Bs00, RT, Ds00, History0, Results0) ->
 	    exit(Eval0, kill),
 	    {_,Eval,_,_} = shell_rep(Eval0, Bs0, RT, Ds0),
 	    server_loop(N0, Eval, Bs0, RT, Ds0, History0, Results0);
-	{error,tokens} ->			%Most probably unicode > 255
+	{error,tokens} ->			%Most probably character > 255
             fwrite_severity(benign, <<"~w: Invalid tokens.">>, 
                             [N]),
 	    server_loop(N0, Eval0, Bs0, RT, Ds0, History0, Results0);
@@ -290,7 +290,10 @@ server_loop(N0, Eval_0, Bs00, RT, Ds00, History0, Results0) ->
     end.
 
 get_command(Prompt, Eval, Bs, RT, Ds) ->
-    Parse = fun() -> exit(io:parse_erl_exprs(Prompt)) end,
+    Parse =
+        fun() ->
+                exit(io:parse_erl_exprs(group_leader(), Prompt, 1, [unicode]))
+        end,
     Pid = spawn_link(Parse),
     get_command1(Pid, Eval, Bs, RT, Ds).
 
@@ -337,7 +340,7 @@ get_prompt_func() ->
     end.
 
 bad_prompt_func(M) ->
-    fwrite_severity(benign, <<"Bad prompt function: ~p">>, [M]).
+    fwrite_severity(benign, "Bad prompt function: ~"++cs_p(), [M]).
 
 default_prompt(N) ->
     %% Don't bother flattening the list irrespective of what the
@@ -453,7 +456,8 @@ expand_bin_elements([{bin_element,L,E,Sz,Ts}|Fs], C) ->
 
 no_command(N) ->
     throw({error,
-           io_lib:fwrite(<<"~s: command not found">>, [erl_pp:expr(N)])}).
+           io_lib:fwrite(<<"~ts: command not found">>,
+                         [erl_pp:expr(N, enc())])}).
 
 %% add_cmd(Number, Expressions, Value)
 %% get_cmd(Number, CurrentCommand)
@@ -518,7 +522,7 @@ shell_rep(Ev, Bs0, RT, Ds0) ->
 	{shell_rep,Ev,{value,V,Bs,Ds}} ->
 	    {V,Ev,Bs,Ds};
         {shell_rep,Ev,{command_error,{Line,M,Error}}} -> 
-            fwrite_severity(benign, <<"~w: ~s">>, 
+            fwrite_severity(benign, <<"~w: ~ts">>,
                             [Line, M:format_error(Error)]),
             {{'EXIT',Error},Ev,Bs0,Ds0};
 	{shell_req,Ev,get_cmd} ->
@@ -570,9 +574,10 @@ report_exception(Class, Severity, {Reason,Stacktrace}, RT) ->
     I = iolist_size(Tag) + 1,
     PF = fun(Term, I1) -> pp(Term, I1, RT) end,
     SF = fun(M, _F, _A) -> (M =:= erl_eval) or (M =:= ?MODULE) end,
-    io:requests([{put_chars, Tag},
-                 {put_chars, 
-                  lib:format_exception(I, Class, Reason, Stacktrace, SF, PF)},
+    Enc = encoding(),
+    Str = lib:format_exception(I, Class, Reason, Stacktrace, SF, PF, Enc),
+    io:requests([{put_chars, latin1, Tag},
+                 {put_chars, unicode, Str},
                  nl]).
 
 start_eval(Bs, RT, Ds) ->
@@ -671,7 +676,8 @@ exprs([E0|Es], Bs1, RT, Lf, Ef, Bs0, W) ->
             if
                 Es =:= [] ->
                     VS = pp(V0, 1, RT),
-                    [io:requests([{put_chars, VS}, nl]) || W =:= cmd],
+                    [io:requests([{put_chars, unicode, VS}, nl]) ||
+                        W =:= cmd],
                     %% Don't send the result back if it will be
                     %% discarded anyway.
                     V = if
@@ -753,7 +759,7 @@ used_records(E) ->
     {expr, E}.
 
 fwrite_severity(Severity, S, As) ->
-    io:fwrite(<<"~s\n">>, [format_severity(Severity, S, As)]).
+    io:fwrite(<<"~ts\n">>, [format_severity(Severity, S, As)]).
 
 format_severity(Severity, S, As) ->
     add_severity(Severity, io_lib:fwrite(S, As)).
@@ -958,13 +964,13 @@ local_func(rd, [{atom,_,RecName},RecDef0], Bs, _Shell, RT, _Lf, _Ef) ->
     RecDef = expand_value(RecDef0),
     RDs = lists:flatten(erl_pp:expr(RecDef)),
     Attr = lists:concat(["-record('", RecName, "',", RDs, ")."]),
-    {ok, Tokens, _} = erl_scan:string(Attr),
+    {ok, Tokens, _} = erl_scan:string(Attr, 1, [unicode]),
     case erl_parse:parse_form(Tokens) of
         {ok,AttrForm} ->
             [RN] = add_records([AttrForm], Bs, RT),
             {value,RN,Bs};
         {error,{_Line,M,ErrDesc}} ->
-            ErrStr = io_lib:fwrite(<<"~s">>, [M:format_error(ErrDesc)]),
+            ErrStr = io_lib:fwrite(<<"~ts">>, [M:format_error(ErrDesc)]),
             exit(lists:flatten(ErrStr))
     end;
 local_func(rd, [_,_], _Bs, _Shell, _RT, _Lf, _Ef) ->
@@ -988,11 +994,13 @@ local_func(rl, [A], Bs0, _Shell, RT, Lf, Ef) ->
     {value,list_records(record_defs(RT, listify(Recs))),Bs};
 local_func(rp, [A], Bs0, _Shell, RT, Lf, Ef) ->
     {[V],Bs} = expr_list([A], Bs0, Lf, Ef),
-    W = columns(),
-    io:requests([{put_chars, 
-                  io_lib_pretty:print(V, 1, W, -1, ?CHAR_MAX,
-                                      record_print_fun(RT))},
-                 nl]),
+    Cs = io_lib_pretty:print(V, ([{column, 1},
+                                  {line_length, columns()},
+                                  {depth, -1},
+                                  {max_chars, ?CHAR_MAX},
+                                  {record_print_fun, record_print_fun(RT)}]
+                                 ++ enc())),
+    io:requests([{put_chars, unicode, Cs}, nl]),
     {value,ok,Bs};
 local_func(rr, [A], Bs0, _Shell, RT, Lf, Ef) ->
     {[File],Bs} = expr_list([A], Bs0, Lf, Ef),
@@ -1166,7 +1174,7 @@ add_records(RAs, Bs0, RT) ->
     case check_command([], Bs1) of
         {error,{_Line,M,ErrDesc}} ->
             %% A source file that has not been compiled.
-            ErrStr = io_lib:fwrite(<<"~s">>, [M:format_error(ErrDesc)]),
+            ErrStr = io_lib:fwrite(<<"~ts">>, [M:format_error(ErrDesc)]),
             exit(lists:flatten(ErrStr));
         ok ->
             true = ets:insert(RT, Recs),
@@ -1343,25 +1351,25 @@ list_commands([{{N,command},Es0}, {{N,result}, V} |Ds], RT) ->
     VS = pp(V, 4, RT),
     Ns = io_lib:fwrite(<<"~w: ">>, [N]),
     I = iolist_size(Ns),
-    io:requests([{put_chars, Ns},
-                 {format,<<"~s\n">>,[erl_pp:exprs(Es, I, none)]},
+    io:requests([{put_chars, latin1, Ns},
+                 {format,<<"~ts\n">>,[erl_pp:exprs(Es, I, enc())]},
 		 {format,<<"-> ">>,[]},
-                 {put_chars, VS},
+                 {put_chars, unicode, VS},
                  nl]),
     list_commands(Ds, RT);
 list_commands([{{N,command},Es0} |Ds], RT) ->
     Es = prep_list_commands(Es0),
     Ns = io_lib:fwrite(<<"~w: ">>, [N]),
     I = iolist_size(Ns),
-    io:requests([{put_chars, Ns},
-                 {format,<<"~s\n">>,[erl_pp:exprs(Es, I, none)]}]),
+    io:requests([{put_chars, latin1, Ns},
+                 {format,<<"~ts\n">>,[erl_pp:exprs(Es, I, enc())]}]),
     list_commands(Ds, RT);
 list_commands([_D|Ds], RT) ->
     list_commands(Ds, RT);
 list_commands([], _RT) -> ok.
 
 list_bindings([{{module,M},Val}|Bs], RT) ->
-    io:fwrite(<<"~p is ~p\n">>, [M,Val]),
+    io:fwrite(<<"~w is ~w\n">>, [M,Val]),
     list_bindings(Bs, RT);
 list_bindings([{Name,Val}|Bs], RT) ->
     case erl_eval:fun_data(Val) of
@@ -1369,13 +1377,13 @@ list_bindings([{Name,Val}|Bs], RT) ->
             FCs = expand_value(FCs0), % looks nicer
             F = {'fun',0,{clauses,FCs}},
             M = {match,0,{var,0,Name},F},
-            io:fwrite(<<"~s\n">>, [erl_pp:expr(M)]);
+            io:fwrite(<<"~ts\n">>, [erl_pp:expr(M, enc())]);
         false ->
             Namel = io_lib:fwrite(<<"~s = ">>, [Name]),
             Nl = iolist_size(Namel)+1,
             ValS = pp(Val, Nl, RT),
-            io:requests([{put_chars, Namel},
-                         {put_chars, ValS},
+            io:requests([{put_chars, latin1, Namel},
+                         {put_chars, unicode, ValS},
                          nl])
     end,
     list_bindings(Bs, RT);
@@ -1384,7 +1392,7 @@ list_bindings([], _RT) ->
 
 list_records(Records) ->
     lists:foreach(fun({_Name,Attr}) -> 
-                          io:fwrite(<<"~s">>, [erl_pp:attribute(Attr)])
+                          io:fwrite(<<"~ts">>, [erl_pp:attribute(Attr, enc())])
                   end, Records).
 
 record_defs(RT, Names) ->
@@ -1427,8 +1435,20 @@ get_history_and_results() ->
     {History, erlang:min(Results, History)}.
 
 pp(V, I, RT) ->
-    io_lib_pretty:print(V, I, columns(), ?LINEMAX, ?CHAR_MAX,
-                        record_print_fun(RT)).
+    pp(V, I, RT, enc()).
+
+pp(V, I, RT, Enc) ->
+    io_lib_pretty:print(V, ([{column, I}, {line_length, columns()},
+                             {depth, ?LINEMAX}, {max_chars, ?CHAR_MAX},
+                             {record_print_fun, record_print_fun(RT)}]
+                            ++ Enc)).
+
+%% Control sequence 'p' possibly with Unicode translation modifier
+cs_p() ->
+    case encoding() of
+        latin1 -> "p";
+        unicode -> "tp"
+    end.
 
 columns() ->
     case io:columns() of
@@ -1436,6 +1456,16 @@ columns() ->
         _ -> 80
     end.
 
+encoding() ->
+    [{encoding, Encoding}] = enc(),
+    Encoding.
+
+enc() ->
+    case lists:keyfind(encoding, 1, io:getopts()) of
+        false -> [{encoding,latin1}]; % should never happen
+        Enc -> [Enc]
+    end.
+
 garb(Shell) ->
     erlang:garbage_collect(Shell),
     catch erlang:garbage_collect(whereis(user)),
@@ -1458,7 +1488,8 @@ check_env(V) ->
 	    ok;
         {ok, Val} ->
             Txt = io_lib:fwrite(
-              <<"Invalid value of STDLIB configuration parameter ~p: ~p\n">>,
+                    ("Invalid value of STDLIB configuration parameter ~w: ~"
+                     ++cs_p()++"\n"),
                     [V, Val]),
 	    error_logger:info_report(lists:flatten(Txt))
     end.