--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/gcc/ada/libgnat/a-textio.adb	Fri Oct 27 22:46:09 2017 +0900
@@ -0,0 +1,2182 @@
+------------------------------------------------------------------------------
+--                                                                          --
+--                         GNAT RUN-TIME COMPONENTS                         --
+--                                                                          --
+--                          A D A . T E X T _ I O                           --
+--                                                                          --
+--                                 B o d y                                  --
+--                                                                          --
+--          Copyright (C) 1992-2017, Free Software Foundation, Inc.         --
+--                                                                          --
+-- GNAT is free software;  you can  redistribute it  and/or modify it under --
+-- terms of the  GNU General Public License as published  by the Free Soft- --
+-- ware  Foundation;  either version 3,  or (at your option) any later ver- --
+-- sion.  GNAT is distributed in the hope that it will be useful, but WITH- --
+-- OUT ANY WARRANTY;  without even the  implied warranty of MERCHANTABILITY --
+-- or FITNESS FOR A PARTICULAR PURPOSE.                                     --
+--                                                                          --
+-- As a special exception under Section 7 of GPL version 3, you are granted --
+-- additional permissions described in the GCC Runtime Library Exception,   --
+-- version 3.1, as published by the Free Software Foundation.               --
+--                                                                          --
+-- You should have received a copy of the GNU General Public License and    --
+-- a copy of the GCC Runtime Library Exception along with this program;     --
+-- see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see    --
+-- <http://www.gnu.org/licenses/>.                                          --
+--                                                                          --
+-- GNAT was originally developed  by the GNAT team at  New York University. --
+-- Extensive contributions were provided by Ada Core Technologies Inc.      --
+--                                                                          --
+------------------------------------------------------------------------------
+
+with Ada.Streams;             use Ada.Streams;
+with Interfaces.C_Streams;    use Interfaces.C_Streams;
+
+with System.File_IO;
+with System.CRTL;
+with System.WCh_Cnv;          use System.WCh_Cnv;
+with System.WCh_Con;          use System.WCh_Con;
+
+with Ada.Unchecked_Conversion;
+with Ada.Unchecked_Deallocation;
+
+pragma Elaborate_All (System.File_IO);
+--  Needed because of calls to Chain_File in package body elaboration
+
+package body Ada.Text_IO is
+
+   package FIO renames System.File_IO;
+
+   subtype AP is FCB.AFCB_Ptr;
+
+   function To_FCB is new Ada.Unchecked_Conversion (File_Mode, FCB.File_Mode);
+   function To_TIO is new Ada.Unchecked_Conversion (FCB.File_Mode, File_Mode);
+   use type FCB.File_Mode;
+
+   use type System.CRTL.size_t;
+
+   WC_Encoding : Character;
+   pragma Import (C, WC_Encoding, "__gl_wc_encoding");
+   --  Default wide character encoding
+
+   Err_Name : aliased String := "*stderr" & ASCII.NUL;
+   In_Name  : aliased String := "*stdin" & ASCII.NUL;
+   Out_Name : aliased String := "*stdout" & ASCII.NUL;
+   --  Names of standard files
+   --
+   --  Use "preallocated" strings to avoid calling "new" during the elaboration
+   --  of the run time. This is needed in the tasking case to avoid calling
+   --  Task_Lock too early. A filename is expected to end with a null character
+   --  in the runtime, here the null characters are added just to have a
+   --  correct filename length.
+   --
+   --  Note: the names for these files are bogus, and probably it would be
+   --  better for these files to have no names, but the ACVC tests insist.
+   --  We use names that are bound to fail in open etc.
+
+   Null_Str : aliased constant String := "";
+   --  Used as form string for standard files
+
+   -----------------------
+   -- Local Subprograms --
+   -----------------------
+
+   function Get_Upper_Half_Char
+     (C    : Character;
+      File : File_Type) return Character;
+   --  This function is shared by Get and Get_Immediate to extract an encoded
+   --  upper half character value from the given File. The first byte has
+   --  already been read and is passed in C. The character value is returned as
+   --  the result, and the file pointer is bumped past the character.
+   --  Constraint_Error is raised if the encoded value is outside the bounds of
+   --  type Character.
+
+   function Get_Upper_Half_Char_Immed
+     (C    : Character;
+      File : File_Type) return Character;
+   --  This routine is identical to Get_Upper_Half_Char, except that the reads
+   --  are done in Get_Immediate mode (i.e. without waiting for a line return).
+
+   function Getc (File : File_Type) return int;
+   --  Gets next character from file, which has already been checked for being
+   --  in read status, and returns the character read if no error occurs. The
+   --  result is EOF if the end of file was read.
+
+   function Getc_Immed (File : File_Type) return int;
+   --  This routine is identical to Getc, except that the read is done in
+   --  Get_Immediate mode (i.e. without waiting for a line return).
+
+   function Has_Upper_Half_Character (Item : String) return Boolean;
+   --  Returns True if any of the characters is in the range 16#80#-16#FF#
+
+   function Nextc (File : File_Type) return int;
+   --  Returns next character from file without skipping past it (i.e. it is a
+   --  combination of Getc followed by an Ungetc).
+
+   procedure Put_Encoded (File : File_Type; Char : Character);
+   --  Called to output a character Char to the given File, when the encoding
+   --  method for the file is other than brackets, and Char is upper half.
+
+   procedure Putc (ch : int; File : File_Type);
+   --  Outputs the given character to the file, which has already been checked
+   --  for being in output status. Device_Error is raised if the character
+   --  cannot be written.
+
+   procedure Set_WCEM (File : in out File_Type);
+   --  Called by Open and Create to set the wide character encoding method for
+   --  the file, processing a WCEM form parameter if one is present. File is
+   --  IN OUT because it may be closed in case of an error.
+
+   procedure Terminate_Line (File : File_Type);
+   --  If the file is in Write_File or Append_File mode, and the current line
+   --  is not terminated, then a line terminator is written using New_Line.
+   --  Note that there is no Terminate_Page routine, because the page mark at
+   --  the end of the file is implied if necessary.
+
+   procedure Ungetc (ch : int; File : File_Type);
+   --  Pushes back character into stream, using ungetc. The caller has checked
+   --  that the file is in read status. Device_Error is raised if the character
+   --  cannot be pushed back. An attempt to push back and end of file character
+   --  (EOF) is ignored.
+
+   -------------------
+   -- AFCB_Allocate --
+   -------------------
+
+   function AFCB_Allocate (Control_Block : Text_AFCB) return FCB.AFCB_Ptr is
+      pragma Unreferenced (Control_Block);
+   begin
+      return new Text_AFCB;
+   end AFCB_Allocate;
+
+   ----------------
+   -- AFCB_Close --
+   ----------------
+
+   procedure AFCB_Close (File : not null access Text_AFCB) is
+   begin
+      --  If the file being closed is one of the current files, then close
+      --  the corresponding current file. It is not clear that this action
+      --  is required (RM A.10.3(23)) but it seems reasonable, and besides
+      --  ACVC test CE3208A expects this behavior.
+
+      if File_Type (File) = Current_In then
+         Current_In := null;
+      elsif File_Type (File) = Current_Out then
+         Current_Out := null;
+      elsif File_Type (File) = Current_Err then
+         Current_Err := null;
+      end if;
+
+      Terminate_Line (File_Type (File));
+   end AFCB_Close;
+
+   ---------------
+   -- AFCB_Free --
+   ---------------
+
+   procedure AFCB_Free (File : not null access Text_AFCB) is
+      type FCB_Ptr is access all Text_AFCB;
+      FT : FCB_Ptr := FCB_Ptr (File);
+
+      procedure Free is new Ada.Unchecked_Deallocation (Text_AFCB, FCB_Ptr);
+
+   begin
+      Free (FT);
+   end AFCB_Free;
+
+   -----------
+   -- Close --
+   -----------
+
+   procedure Close (File : in out File_Type) is
+   begin
+      FIO.Close (AP (File)'Unrestricted_Access);
+   end Close;
+
+   ---------
+   -- Col --
+   ---------
+
+   --  Note: we assume that it is impossible in practice for the column
+   --  to exceed the value of Count'Last, i.e. no check is required for
+   --  overflow raising layout error.
+
+   function Col (File : File_Type) return Positive_Count is
+   begin
+      FIO.Check_File_Open (AP (File));
+      return File.Col;
+   end Col;
+
+   function Col return Positive_Count is
+   begin
+      return Col (Current_Out);
+   end Col;
+
+   ------------
+   -- Create --
+   ------------
+
+   procedure Create
+     (File : in out File_Type;
+      Mode : File_Mode := Out_File;
+      Name : String := "";
+      Form : String := "")
+   is
+      Dummy_File_Control_Block : Text_AFCB;
+      pragma Warnings (Off, Dummy_File_Control_Block);
+      --  Yes, we know this is never assigned a value, only the tag
+      --  is used for dispatching purposes, so that's expected.
+
+   begin
+      FIO.Open (File_Ptr  => AP (File),
+                Dummy_FCB => Dummy_File_Control_Block,
+                Mode      => To_FCB (Mode),
+                Name      => Name,
+                Form      => Form,
+                Amethod   => 'T',
+                Creat     => True,
+                Text      => True);
+
+      File.Self := File;
+      Set_WCEM (File);
+   end Create;
+
+   -------------------
+   -- Current_Error --
+   -------------------
+
+   function Current_Error return File_Type is
+   begin
+      return Current_Err;
+   end Current_Error;
+
+   function Current_Error return File_Access is
+   begin
+      return Current_Err.Self'Access;
+   end Current_Error;
+
+   -------------------
+   -- Current_Input --
+   -------------------
+
+   function Current_Input return File_Type is
+   begin
+      return Current_In;
+   end Current_Input;
+
+   function Current_Input return File_Access is
+   begin
+      return Current_In.Self'Access;
+   end Current_Input;
+
+   --------------------
+   -- Current_Output --
+   --------------------
+
+   function Current_Output return File_Type is
+   begin
+      return Current_Out;
+   end Current_Output;
+
+   function Current_Output return File_Access is
+   begin
+      return Current_Out.Self'Access;
+   end Current_Output;
+
+   ------------
+   -- Delete --
+   ------------
+
+   procedure Delete (File : in out File_Type) is
+   begin
+      FIO.Delete (AP (File)'Unrestricted_Access);
+   end Delete;
+
+   -----------------
+   -- End_Of_File --
+   -----------------
+
+   function End_Of_File (File : File_Type) return Boolean is
+      ch : int;
+
+   begin
+      FIO.Check_Read_Status (AP (File));
+
+      if File.Before_Upper_Half_Character then
+         return False;
+
+      elsif File.Before_LM then
+         if File.Before_LM_PM then
+            return Nextc (File) = EOF;
+         end if;
+
+      else
+         ch := Getc (File);
+
+         if ch = EOF then
+            return True;
+
+         elsif ch /= LM then
+            Ungetc (ch, File);
+            return False;
+
+         else -- ch = LM
+            File.Before_LM := True;
+         end if;
+      end if;
+
+      --  Here we are just past the line mark with Before_LM set so that we
+      --  do not have to try to back up past the LM, thus avoiding the need
+      --  to back up more than one character.
+
+      ch := Getc (File);
+
+      if ch = EOF then
+         return True;
+
+      elsif ch = PM and then File.Is_Regular_File then
+         File.Before_LM_PM := True;
+         return Nextc (File) = EOF;
+
+      --  Here if neither EOF nor PM followed end of line
+
+      else
+         Ungetc (ch, File);
+         return False;
+      end if;
+
+   end End_Of_File;
+
+   function End_Of_File return Boolean is
+   begin
+      return End_Of_File (Current_In);
+   end End_Of_File;
+
+   -----------------
+   -- End_Of_Line --
+   -----------------
+
+   function End_Of_Line (File : File_Type) return Boolean is
+      ch : int;
+
+   begin
+      FIO.Check_Read_Status (AP (File));
+
+      if File.Before_Upper_Half_Character then
+         return False;
+
+      elsif File.Before_LM then
+         return True;
+
+      else
+         ch := Getc (File);
+
+         if ch = EOF then
+            return True;
+
+         else
+            Ungetc (ch, File);
+            return (ch = LM);
+         end if;
+      end if;
+   end End_Of_Line;
+
+   function End_Of_Line return Boolean is
+   begin
+      return End_Of_Line (Current_In);
+   end End_Of_Line;
+
+   -----------------
+   -- End_Of_Page --
+   -----------------
+
+   function End_Of_Page (File : File_Type) return Boolean is
+      ch  : int;
+
+   begin
+      FIO.Check_Read_Status (AP (File));
+
+      if not File.Is_Regular_File then
+         return False;
+
+      elsif File.Before_Upper_Half_Character then
+         return False;
+
+      elsif File.Before_LM then
+         if File.Before_LM_PM then
+            return True;
+         end if;
+
+      else
+         ch := Getc (File);
+
+         if ch = EOF then
+            return True;
+
+         elsif ch /= LM then
+            Ungetc (ch, File);
+            return False;
+
+         else -- ch = LM
+            File.Before_LM := True;
+         end if;
+      end if;
+
+      --  Here we are just past the line mark with Before_LM set so that we
+      --  do not have to try to back up past the LM, thus avoiding the need
+      --  to back up more than one character.
+
+      ch := Nextc (File);
+
+      return ch = PM or else ch = EOF;
+   end End_Of_Page;
+
+   function End_Of_Page return Boolean is
+   begin
+      return End_Of_Page (Current_In);
+   end End_Of_Page;
+
+   --------------
+   -- EOF_Char --
+   --------------
+
+   function EOF_Char return Integer is
+   begin
+      return EOF;
+   end EOF_Char;
+
+   -----------
+   -- Flush --
+   -----------
+
+   procedure Flush (File : File_Type) is
+   begin
+      FIO.Flush (AP (File));
+   end Flush;
+
+   procedure Flush is
+   begin
+      Flush (Current_Out);
+   end Flush;
+
+   ----------
+   -- Form --
+   ----------
+
+   function Form (File : File_Type) return String is
+   begin
+      return FIO.Form (AP (File));
+   end Form;
+
+   ---------
+   -- Get --
+   ---------
+
+   procedure Get
+     (File : File_Type;
+      Item : out Character)
+   is
+      ch : int;
+
+   begin
+      FIO.Check_Read_Status (AP (File));
+
+      if File.Before_Upper_Half_Character then
+         File.Before_Upper_Half_Character := False;
+         Item := File.Saved_Upper_Half_Character;
+
+      elsif File.Before_LM then
+         File.Before_LM := False;
+         File.Col := 1;
+
+         if File.Before_LM_PM then
+            File.Line := 1;
+            File.Page := File.Page + 1;
+            File.Before_LM_PM := False;
+         else
+            File.Line := File.Line + 1;
+         end if;
+      end if;
+
+      loop
+         ch := Getc (File);
+
+         if ch = EOF then
+            raise End_Error;
+
+         elsif ch = LM then
+            File.Line := File.Line + 1;
+            File.Col := 1;
+
+         elsif ch = PM and then File.Is_Regular_File then
+            File.Page := File.Page + 1;
+            File.Line := 1;
+
+         else
+            Item := Character'Val (ch);
+            File.Col := File.Col + 1;
+            return;
+         end if;
+      end loop;
+   end Get;
+
+   procedure Get (Item : out Character) is
+   begin
+      Get (Current_In, Item);
+   end Get;
+
+   procedure Get
+     (File : File_Type;
+      Item : out String)
+   is
+      ch : int;
+      J  : Natural;
+
+   begin
+      FIO.Check_Read_Status (AP (File));
+
+      if File.Before_LM then
+         File.Before_LM := False;
+         File.Before_LM_PM := False;
+         File.Col := 1;
+
+         if File.Before_LM_PM then
+            File.Line := 1;
+            File.Page := File.Page + 1;
+            File.Before_LM_PM := False;
+
+         else
+            File.Line := File.Line + 1;
+         end if;
+      end if;
+
+      J := Item'First;
+      while J <= Item'Last loop
+         ch := Getc (File);
+
+         if ch = EOF then
+            raise End_Error;
+
+         elsif ch = LM then
+            File.Line := File.Line + 1;
+            File.Col := 1;
+
+         elsif ch = PM and then File.Is_Regular_File then
+            File.Page := File.Page + 1;
+            File.Line := 1;
+
+         else
+            Item (J) := Character'Val (ch);
+            J := J + 1;
+            File.Col := File.Col + 1;
+         end if;
+      end loop;
+   end Get;
+
+   procedure Get (Item : out String) is
+   begin
+      Get (Current_In, Item);
+   end Get;
+
+   -------------------
+   -- Get_Immediate --
+   -------------------
+
+   procedure Get_Immediate
+     (File : File_Type;
+      Item : out Character)
+   is
+      ch          : int;
+
+   begin
+      FIO.Check_Read_Status (AP (File));
+
+      if File.Before_Upper_Half_Character then
+         File.Before_Upper_Half_Character := False;
+         Item := File.Saved_Upper_Half_Character;
+
+      elsif File.Before_LM then
+         File.Before_LM := False;
+         File.Before_LM_PM := False;
+         Item := Character'Val (LM);
+
+      else
+         ch := Getc_Immed (File);
+
+         if ch = EOF then
+            raise End_Error;
+         else
+            Item :=
+              (if not Is_Start_Of_Encoding (Character'Val (ch), File.WC_Method)
+               then Character'Val (ch)
+               else Get_Upper_Half_Char_Immed (Character'Val (ch), File));
+         end if;
+      end if;
+   end Get_Immediate;
+
+   procedure Get_Immediate
+     (Item : out Character)
+   is
+   begin
+      Get_Immediate (Current_In, Item);
+   end Get_Immediate;
+
+   procedure Get_Immediate
+     (File      : File_Type;
+      Item      : out Character;
+      Available : out Boolean)
+   is
+      ch          : int;
+      end_of_file : int;
+      avail       : int;
+
+      procedure getc_immediate_nowait
+        (stream      : FILEs;
+         ch          : out int;
+         end_of_file : out int;
+         avail       : out int);
+      pragma Import (C, getc_immediate_nowait, "getc_immediate_nowait");
+
+   begin
+      FIO.Check_Read_Status (AP (File));
+      Available := True;
+
+      if File.Before_Upper_Half_Character then
+         File.Before_Upper_Half_Character := False;
+         Item := File.Saved_Upper_Half_Character;
+
+      elsif File.Before_LM then
+         File.Before_LM := False;
+         File.Before_LM_PM := False;
+         Item := Character'Val (LM);
+
+      else
+         getc_immediate_nowait (File.Stream, ch, end_of_file, avail);
+
+         if ferror (File.Stream) /= 0 then
+            raise Device_Error;
+
+         elsif end_of_file /= 0 then
+            raise End_Error;
+
+         elsif avail = 0 then
+            Available := False;
+            Item := ASCII.NUL;
+
+         else
+            Available := True;
+
+            Item :=
+              (if not Is_Start_Of_Encoding (Character'Val (ch), File.WC_Method)
+               then Character'Val (ch)
+               else Get_Upper_Half_Char_Immed (Character'Val (ch), File));
+         end if;
+      end if;
+
+   end Get_Immediate;
+
+   procedure Get_Immediate
+     (Item      : out Character;
+      Available : out Boolean)
+   is
+   begin
+      Get_Immediate (Current_In, Item, Available);
+   end Get_Immediate;
+
+   --------------
+   -- Get_Line --
+   --------------
+
+   procedure Get_Line
+     (File : File_Type;
+      Item : out String;
+      Last : out Natural) is separate;
+   --  The implementation of Ada.Text_IO.Get_Line is split into a subunit so
+   --  that different implementations can be used on different systems.
+
+   procedure Get_Line
+     (Item : out String;
+      Last : out Natural)
+   is
+   begin
+      Get_Line (Current_In, Item, Last);
+   end Get_Line;
+
+   function Get_Line (File : File_Type) return String is
+      function Get_Rest (S : String) return String;
+      --  This is a recursive function that reads the rest of the line and
+      --  returns it. S is the part read so far.
+
+      --------------
+      -- Get_Rest --
+      --------------
+
+      function Get_Rest (S : String) return String is
+
+         --  The first time we allocate a buffer of size 500. Each following
+         --  time we allocate a buffer the same size as what we have read so
+         --  far. This limits us to a logarithmic number of calls to Get_Rest
+         --  and also ensures only a linear use of stack space.
+
+         Buffer : String (1 .. Integer'Max (500, S'Length));
+         Last   : Natural;
+
+      begin
+         Get_Line (File, Buffer, Last);
+
+         declare
+            R : constant String := S & Buffer (1 .. Last);
+         begin
+            if Last < Buffer'Last then
+               return R;
+
+            else
+               pragma Assert (Last = Buffer'Last);
+
+               --  If the String has the same length as the buffer, and there
+               --  is no end of line, check whether we are at the end of file,
+               --  in which case we have the full String in the buffer.
+
+               if End_Of_File (File) then
+                  return R;
+
+               else
+                  return Get_Rest (R);
+               end if;
+            end if;
+         end;
+      end Get_Rest;
+
+   --  Start of processing for Get_Line
+
+   begin
+      return Get_Rest ("");
+   end Get_Line;
+
+   function Get_Line return String is
+   begin
+      return Get_Line (Current_In);
+   end Get_Line;
+
+   -------------------------
+   -- Get_Upper_Half_Char --
+   -------------------------
+
+   function Get_Upper_Half_Char
+     (C    : Character;
+      File : File_Type) return Character
+   is
+      Result : Wide_Character;
+
+      function In_Char return Character;
+      --  Function used to obtain additional characters it the wide character
+      --  sequence is more than one character long.
+
+      function WC_In is new Char_Sequence_To_Wide_Char (In_Char);
+
+      -------------
+      -- In_Char --
+      -------------
+
+      function In_Char return Character is
+         ch : constant Integer := Getc (File);
+      begin
+         if ch = EOF then
+            raise End_Error;
+         else
+            return Character'Val (ch);
+         end if;
+      end In_Char;
+
+   --  Start of processing for Get_Upper_Half_Char
+
+   begin
+      Result := WC_In (C, File.WC_Method);
+
+      if Wide_Character'Pos (Result) > 16#FF# then
+         raise Constraint_Error with
+           "invalid wide character in Text_'I'O input";
+      else
+         return Character'Val (Wide_Character'Pos (Result));
+      end if;
+   end Get_Upper_Half_Char;
+
+   -------------------------------
+   -- Get_Upper_Half_Char_Immed --
+   -------------------------------
+
+   function Get_Upper_Half_Char_Immed
+     (C    : Character;
+      File : File_Type) return Character
+   is
+      Result : Wide_Character;
+
+      function In_Char return Character;
+      --  Function used to obtain additional characters it the wide character
+      --  sequence is more than one character long.
+
+      function WC_In is new Char_Sequence_To_Wide_Char (In_Char);
+
+      -------------
+      -- In_Char --
+      -------------
+
+      function In_Char return Character is
+         ch : constant Integer := Getc_Immed (File);
+      begin
+         if ch = EOF then
+            raise End_Error;
+         else
+            return Character'Val (ch);
+         end if;
+      end In_Char;
+
+   --  Start of processing for Get_Upper_Half_Char_Immed
+
+   begin
+      Result := WC_In (C, File.WC_Method);
+
+      if Wide_Character'Pos (Result) > 16#FF# then
+         raise Constraint_Error with
+           "invalid wide character in Text_'I'O input";
+      else
+         return Character'Val (Wide_Character'Pos (Result));
+      end if;
+   end Get_Upper_Half_Char_Immed;
+
+   ----------
+   -- Getc --
+   ----------
+
+   function Getc (File : File_Type) return int is
+      ch : int;
+
+   begin
+      ch := fgetc (File.Stream);
+
+      if ch = EOF and then ferror (File.Stream) /= 0 then
+         raise Device_Error;
+      else
+         return ch;
+      end if;
+   end Getc;
+
+   ----------------
+   -- Getc_Immed --
+   ----------------
+
+   function Getc_Immed (File : File_Type) return int is
+      ch          : int;
+      end_of_file : int;
+
+      procedure getc_immediate
+        (stream : FILEs; ch : out int; end_of_file : out int);
+      pragma Import (C, getc_immediate, "getc_immediate");
+
+   begin
+      FIO.Check_Read_Status (AP (File));
+
+      if File.Before_LM then
+         File.Before_LM := False;
+         File.Before_LM_PM := False;
+         ch := LM;
+
+      else
+         getc_immediate (File.Stream, ch, end_of_file);
+
+         if ferror (File.Stream) /= 0 then
+            raise Device_Error;
+         elsif end_of_file /= 0 then
+            return EOF;
+         end if;
+      end if;
+
+      return ch;
+   end Getc_Immed;
+
+   ------------------------------
+   -- Has_Upper_Half_Character --
+   ------------------------------
+
+   function Has_Upper_Half_Character (Item : String) return Boolean is
+   begin
+      for J in Item'Range loop
+         if Character'Pos (Item (J)) >= 16#80# then
+            return True;
+         end if;
+      end loop;
+
+      return False;
+   end Has_Upper_Half_Character;
+
+   -------------------------------
+   -- Initialize_Standard_Files --
+   -------------------------------
+
+   procedure Initialize_Standard_Files is
+   begin
+      Standard_Err.Stream            := stderr;
+      Standard_Err.Name              := Err_Name'Access;
+      Standard_Err.Form              := Null_Str'Unrestricted_Access;
+      Standard_Err.Mode              := FCB.Out_File;
+      Standard_Err.Is_Regular_File   := is_regular_file (fileno (stderr)) /= 0;
+      Standard_Err.Is_Temporary_File := False;
+      Standard_Err.Is_System_File    := True;
+      Standard_Err.Text_Encoding     := Default_Text;
+      Standard_Err.Access_Method     := 'T';
+      Standard_Err.Self              := Standard_Err;
+      Standard_Err.WC_Method         := Default_WCEM;
+
+      Standard_In.Stream             := stdin;
+      Standard_In.Name               := In_Name'Access;
+      Standard_In.Form               := Null_Str'Unrestricted_Access;
+      Standard_In.Mode               := FCB.In_File;
+      Standard_In.Is_Regular_File    := is_regular_file (fileno (stdin)) /= 0;
+      Standard_In.Is_Temporary_File  := False;
+      Standard_In.Is_System_File     := True;
+      Standard_In.Text_Encoding      := Default_Text;
+      Standard_In.Access_Method      := 'T';
+      Standard_In.Self               := Standard_In;
+      Standard_In.WC_Method          := Default_WCEM;
+
+      Standard_Out.Stream            := stdout;
+      Standard_Out.Name              := Out_Name'Access;
+      Standard_Out.Form              := Null_Str'Unrestricted_Access;
+      Standard_Out.Mode              := FCB.Out_File;
+      Standard_Out.Is_Regular_File   := is_regular_file (fileno (stdout)) /= 0;
+      Standard_Out.Is_Temporary_File := False;
+      Standard_Out.Is_System_File    := True;
+      Standard_Out.Text_Encoding     := Default_Text;
+      Standard_Out.Access_Method     := 'T';
+      Standard_Out.Self              := Standard_Out;
+      Standard_Out.WC_Method         := Default_WCEM;
+
+      FIO.Make_Unbuffered (AP (Standard_Out));
+      FIO.Make_Unbuffered (AP (Standard_Err));
+   end Initialize_Standard_Files;
+
+   -------------
+   -- Is_Open --
+   -------------
+
+   function Is_Open (File : File_Type) return Boolean is
+   begin
+      return FIO.Is_Open (AP (File));
+   end Is_Open;
+
+   ----------
+   -- Line --
+   ----------
+
+   --  Note: we assume that it is impossible in practice for the line
+   --  to exceed the value of Count'Last, i.e. no check is required for
+   --  overflow raising layout error.
+
+   function Line (File : File_Type) return Positive_Count is
+   begin
+      FIO.Check_File_Open (AP (File));
+      return File.Line;
+   end Line;
+
+   function Line return Positive_Count is
+   begin
+      return Line (Current_Out);
+   end Line;
+
+   -----------------
+   -- Line_Length --
+   -----------------
+
+   function Line_Length (File : File_Type) return Count is
+   begin
+      FIO.Check_Write_Status (AP (File));
+      return File.Line_Length;
+   end Line_Length;
+
+   function Line_Length return Count is
+   begin
+      return Line_Length (Current_Out);
+   end Line_Length;
+
+   ----------------
+   -- Look_Ahead --
+   ----------------
+
+   procedure Look_Ahead
+     (File        : File_Type;
+      Item        : out Character;
+      End_Of_Line : out Boolean)
+   is
+      ch : int;
+
+   begin
+      FIO.Check_Read_Status (AP (File));
+
+      --  If we are logically before a line mark, we can return immediately
+
+      if File.Before_LM then
+         End_Of_Line := True;
+         Item := ASCII.NUL;
+
+      --  If we are before an upper half character just return it (this can
+      --  happen if there are two calls to Look_Ahead in a row).
+
+      elsif File.Before_Upper_Half_Character then
+         End_Of_Line := False;
+         Item := File.Saved_Upper_Half_Character;
+
+      --  Otherwise we must read a character from the input stream
+
+      else
+         ch := Getc (File);
+
+         if ch = LM
+           or else ch = EOF
+           or else (ch = PM and then File.Is_Regular_File)
+         then
+            End_Of_Line := True;
+            Ungetc (ch, File);
+            Item := ASCII.NUL;
+
+         --  Case where character obtained does not represent the start of an
+         --  encoded sequence so it stands for itself and we can unget it with
+         --  no difficulty.
+
+         elsif not Is_Start_Of_Encoding
+                     (Character'Val (ch), File.WC_Method)
+         then
+            End_Of_Line := False;
+            Ungetc (ch, File);
+            Item := Character'Val (ch);
+
+         --  For the start of an encoding, we read the character using the
+         --  Get_Upper_Half_Char routine. It will occupy more than one byte
+         --  so we can't put it back with ungetc. Instead we save it in the
+         --  control block, setting a flag that everyone interested in reading
+         --  characters must test before reading the stream.
+
+         else
+            Item := Get_Upper_Half_Char (Character'Val (ch), File);
+            End_Of_Line := False;
+            File.Saved_Upper_Half_Character := Item;
+            File.Before_Upper_Half_Character := True;
+         end if;
+      end if;
+   end Look_Ahead;
+
+   procedure Look_Ahead
+     (Item        : out Character;
+      End_Of_Line : out Boolean)
+   is
+   begin
+      Look_Ahead (Current_In, Item, End_Of_Line);
+   end Look_Ahead;
+
+   ----------
+   -- Mode --
+   ----------
+
+   function Mode (File : File_Type) return File_Mode is
+   begin
+      return To_TIO (FIO.Mode (AP (File)));
+   end Mode;
+
+   ----------
+   -- Name --
+   ----------
+
+   function Name (File : File_Type) return String is
+   begin
+      return FIO.Name (AP (File));
+   end Name;
+
+   --------------
+   -- New_Line --
+   --------------
+
+   procedure New_Line
+     (File    : File_Type;
+      Spacing : Positive_Count := 1)
+   is
+   begin
+      --  Raise Constraint_Error if out of range value. The reason for this
+      --  explicit test is that we don't want junk values around, even if
+      --  checks are off in the caller.
+
+      if not Spacing'Valid then
+         raise Constraint_Error;
+      end if;
+
+      FIO.Check_Write_Status (AP (File));
+
+      for K in 1 .. Spacing loop
+         Putc (LM, File);
+         File.Line := File.Line + 1;
+
+         if File.Page_Length /= 0
+           and then File.Line > File.Page_Length
+         then
+            Putc (PM, File);
+            File.Line := 1;
+            File.Page := File.Page + 1;
+         end if;
+      end loop;
+
+      File.Col := 1;
+   end New_Line;
+
+   procedure New_Line (Spacing : Positive_Count := 1) is
+   begin
+      New_Line (Current_Out, Spacing);
+   end New_Line;
+
+   --------------
+   -- New_Page --
+   --------------
+
+   procedure New_Page (File : File_Type) is
+   begin
+      FIO.Check_Write_Status (AP (File));
+
+      if File.Col /= 1 or else File.Line = 1 then
+         Putc (LM, File);
+      end if;
+
+      Putc (PM, File);
+      File.Page := File.Page + 1;
+      File.Line := 1;
+      File.Col := 1;
+   end New_Page;
+
+   procedure New_Page is
+   begin
+      New_Page (Current_Out);
+   end New_Page;
+
+   -----------
+   -- Nextc --
+   -----------
+
+   function Nextc (File : File_Type) return int is
+      ch : int;
+
+   begin
+      ch := fgetc (File.Stream);
+
+      if ch = EOF then
+         if ferror (File.Stream) /= 0 then
+            raise Device_Error;
+         end if;
+
+      else
+         if ungetc (ch, File.Stream) = EOF then
+            raise Device_Error;
+         end if;
+      end if;
+
+      return ch;
+   end Nextc;
+
+   ----------
+   -- Open --
+   ----------
+
+   procedure Open
+     (File : in out File_Type;
+      Mode : File_Mode;
+      Name : String;
+      Form : String := "")
+   is
+      Dummy_File_Control_Block : Text_AFCB;
+      pragma Warnings (Off, Dummy_File_Control_Block);
+      --  Yes, we know this is never assigned a value, only the tag
+      --  is used for dispatching purposes, so that's expected.
+
+   begin
+      FIO.Open (File_Ptr  => AP (File),
+                Dummy_FCB => Dummy_File_Control_Block,
+                Mode      => To_FCB (Mode),
+                Name      => Name,
+                Form      => Form,
+                Amethod   => 'T',
+                Creat     => False,
+                Text      => True);
+
+      File.Self := File;
+      Set_WCEM (File);
+   end Open;
+
+   ----------
+   -- Page --
+   ----------
+
+   --  Note: we assume that it is impossible in practice for the page
+   --  to exceed the value of Count'Last, i.e. no check is required for
+   --  overflow raising layout error.
+
+   function Page (File : File_Type) return Positive_Count is
+   begin
+      FIO.Check_File_Open (AP (File));
+      return File.Page;
+   end Page;
+
+   function Page return Positive_Count is
+   begin
+      return Page (Current_Out);
+   end Page;
+
+   -----------------
+   -- Page_Length --
+   -----------------
+
+   function Page_Length (File : File_Type) return Count is
+   begin
+      FIO.Check_Write_Status (AP (File));
+      return File.Page_Length;
+   end Page_Length;
+
+   function Page_Length return Count is
+   begin
+      return Page_Length (Current_Out);
+   end Page_Length;
+
+   ---------
+   -- Put --
+   ---------
+
+   procedure Put
+     (File : File_Type;
+      Item : Character)
+   is
+   begin
+      FIO.Check_Write_Status (AP (File));
+
+      if File.Line_Length /= 0 and then File.Col > File.Line_Length then
+         New_Line (File);
+      end if;
+
+      --  If lower half character, or brackets encoding, output directly
+
+      if Character'Pos (Item) < 16#80#
+        or else File.WC_Method = WCEM_Brackets
+      then
+         if fputc (Character'Pos (Item), File.Stream) = EOF then
+            raise Device_Error;
+         end if;
+
+      --  Case of upper half character with non-brackets encoding
+
+      else
+         Put_Encoded (File, Item);
+      end if;
+
+      File.Col := File.Col + 1;
+   end Put;
+
+   procedure Put (Item : Character) is
+   begin
+      Put (Current_Out, Item);
+   end Put;
+
+   ---------
+   -- Put --
+   ---------
+
+   procedure Put
+     (File : File_Type;
+      Item : String)
+   is
+   begin
+      FIO.Check_Write_Status (AP (File));
+
+      --  Only have something to do if string is non-null
+
+      if Item'Length > 0 then
+
+         --  If we have bounded lines, or if the file encoding is other than
+         --  Brackets and the string has at least one upper half character,
+         --  then output the string character by character.
+
+         if File.Line_Length /= 0
+           or else (File.WC_Method /= WCEM_Brackets
+                      and then Has_Upper_Half_Character (Item))
+         then
+            for J in Item'Range loop
+               Put (File, Item (J));
+            end loop;
+
+         --  Otherwise we can output the entire string at once. Note that if
+         --  there are LF or FF characters in the string, we do not bother to
+         --  count them as line or page terminators.
+
+         else
+            FIO.Write_Buf (AP (File), Item'Address, Item'Length);
+            File.Col := File.Col + Item'Length;
+         end if;
+      end if;
+   end Put;
+
+   procedure Put (Item : String) is
+   begin
+      Put (Current_Out, Item);
+   end Put;
+
+   -----------------
+   -- Put_Encoded --
+   -----------------
+
+   procedure Put_Encoded (File : File_Type; Char : Character) is
+      procedure Out_Char (C : Character);
+      --  Procedure to output one character of an upper half encoded sequence
+
+      procedure WC_Out is new Wide_Char_To_Char_Sequence (Out_Char);
+
+      --------------
+      -- Out_Char --
+      --------------
+
+      procedure Out_Char (C : Character) is
+      begin
+         Putc (Character'Pos (C), File);
+      end Out_Char;
+
+   --  Start of processing for Put_Encoded
+
+   begin
+      WC_Out (Wide_Character'Val (Character'Pos (Char)), File.WC_Method);
+   end Put_Encoded;
+
+   --------------
+   -- Put_Line --
+   --------------
+
+   procedure Put_Line
+     (File : File_Type;
+      Item : String)
+   is
+      Ilen   : Natural := Item'Length;
+      Istart : Natural := Item'First;
+
+   begin
+      FIO.Check_Write_Status (AP (File));
+
+      --  If we have bounded lines, or if the file encoding is other than
+      --  Brackets and the string has at least one upper half character, then
+      --  output the string character by character.
+
+      if File.Line_Length /= 0
+        or else (File.WC_Method /= WCEM_Brackets
+                   and then Has_Upper_Half_Character (Item))
+      then
+         for J in Item'Range loop
+            Put (File, Item (J));
+         end loop;
+
+         New_Line (File);
+         return;
+      end if;
+
+      --  Normal case where we do not need to output character by character
+
+      --  We setup a single string that has the necessary terminators and
+      --  then write it with a single call. The reason for doing this is
+      --  that it gives better behavior for the use of Put_Line in multi-
+      --  tasking programs, since often the OS will treat the entire put
+      --  operation as an atomic operation.
+
+      --  We only do this if the message is 512 characters or less in length,
+      --  since otherwise Put_Line would use an unbounded amount of stack
+      --  space and could cause undetected stack overflow. If we have a
+      --  longer string, then output the first part separately to avoid this.
+
+      if Ilen > 512 then
+         FIO.Write_Buf (AP (File), Item'Address, size_t (Ilen - 512));
+         Istart := Istart + Ilen - 512;
+         Ilen   := 512;
+      end if;
+
+      --  Now prepare the string with its terminator
+
+      declare
+         Buffer : String (1 .. Ilen + 2);
+         Plen   : size_t;
+
+      begin
+         Buffer (1 .. Ilen) := Item (Istart .. Item'Last);
+         Buffer (Ilen + 1) := Character'Val (LM);
+
+         if File.Page_Length /= 0
+           and then File.Line > File.Page_Length
+         then
+            Buffer (Ilen + 2) := Character'Val (PM);
+            Plen := size_t (Ilen) + 2;
+            File.Line := 1;
+            File.Page := File.Page + 1;
+
+         else
+            Plen := size_t (Ilen) + 1;
+            File.Line := File.Line + 1;
+         end if;
+
+         FIO.Write_Buf (AP (File), Buffer'Address, Plen);
+
+         File.Col := 1;
+      end;
+   end Put_Line;
+
+   procedure Put_Line (Item : String) is
+   begin
+      Put_Line (Current_Out, Item);
+   end Put_Line;
+
+   ----------
+   -- Putc --
+   ----------
+
+   procedure Putc (ch : int; File : File_Type) is
+   begin
+      if fputc (ch, File.Stream) = EOF then
+         raise Device_Error;
+      end if;
+   end Putc;
+
+   ----------
+   -- Read --
+   ----------
+
+   --  This is the primitive Stream Read routine, used when a Text_IO file
+   --  is treated directly as a stream using Text_IO.Streams.Stream.
+
+   procedure Read
+     (File : in out Text_AFCB;
+      Item : out Stream_Element_Array;
+      Last : out Stream_Element_Offset)
+   is
+      Discard_ch : int;
+      pragma Warnings (Off, Discard_ch);
+
+   begin
+      --  Need to deal with Before_Upper_Half_Character ???
+
+      if File.Mode /= FCB.In_File then
+         raise Mode_Error;
+      end if;
+
+      --  Deal with case where our logical and physical position do not match
+      --  because of being after an LM or LM-PM sequence when in fact we are
+      --  logically positioned before it.
+
+      if File.Before_LM then
+
+         --  If we are before a PM, then it is possible for a stream read
+         --  to leave us after the LM and before the PM, which is a bit
+         --  odd. The easiest way to deal with this is to unget the PM,
+         --  so we are indeed positioned between the characters. This way
+         --  further stream read operations will work correctly, and the
+         --  effect on text processing is a little weird, but what can
+         --  be expected if stream and text input are mixed this way?
+
+         if File.Before_LM_PM then
+            Discard_ch := ungetc (PM, File.Stream);
+            File.Before_LM_PM := False;
+         end if;
+
+         File.Before_LM := False;
+
+         Item (Item'First) := Stream_Element (Character'Pos (ASCII.LF));
+
+         if Item'Length = 1 then
+            Last := Item'Last;
+
+         else
+            Last :=
+              Item'First +
+                Stream_Element_Offset
+                  (fread (buffer => Item'Address,
+                          index  => size_t (Item'First + 1),
+                          size   => 1,
+                          count  => Item'Length - 1,
+                          stream => File.Stream));
+         end if;
+
+         return;
+      end if;
+
+      --  Now we do the read. Since this is a text file, it is normally in
+      --  text mode, but stream data must be read in binary mode, so we
+      --  temporarily set binary mode for the read, resetting it after.
+      --  These calls have no effect in a system (like Unix) where there is
+      --  no distinction between text and binary files.
+
+      set_binary_mode (fileno (File.Stream));
+
+      Last :=
+        Item'First +
+          Stream_Element_Offset
+            (fread (Item'Address, 1, Item'Length, File.Stream)) - 1;
+
+      if Last < Item'Last then
+         if ferror (File.Stream) /= 0 then
+            raise Device_Error;
+         end if;
+      end if;
+
+      set_text_mode (fileno (File.Stream));
+   end Read;
+
+   -----------
+   -- Reset --
+   -----------
+
+   procedure Reset
+     (File : in out File_Type;
+      Mode : File_Mode)
+   is
+   begin
+      --  Don't allow change of mode for current file (RM A.10.2(5))
+
+      if (File = Current_In  or else
+          File = Current_Out or else
+          File = Current_Error)
+        and then To_FCB (Mode) /= File.Mode
+      then
+         raise Mode_Error;
+      end if;
+
+      Terminate_Line (File);
+      FIO.Reset (AP (File)'Unrestricted_Access, To_FCB (Mode));
+      File.Page := 1;
+      File.Line := 1;
+      File.Col  := 1;
+      File.Line_Length := 0;
+      File.Page_Length := 0;
+      File.Before_LM := False;
+      File.Before_LM_PM := False;
+   end Reset;
+
+   procedure Reset (File : in out File_Type) is
+   begin
+      Terminate_Line (File);
+      FIO.Reset (AP (File)'Unrestricted_Access);
+      File.Page := 1;
+      File.Line := 1;
+      File.Col  := 1;
+      File.Line_Length := 0;
+      File.Page_Length := 0;
+      File.Before_LM := False;
+      File.Before_LM_PM := False;
+   end Reset;
+
+   -------------
+   -- Set_Col --
+   -------------
+
+   procedure Set_Col
+     (File : File_Type;
+      To   : Positive_Count)
+   is
+      ch : int;
+
+   begin
+      --  Raise Constraint_Error if out of range value. The reason for this
+      --  explicit test is that we don't want junk values around, even if
+      --  checks are off in the caller.
+
+      if not To'Valid then
+         raise Constraint_Error;
+      end if;
+
+      FIO.Check_File_Open (AP (File));
+
+      --  Output case
+
+      if Mode (File) >= Out_File then
+
+         --  Error if we attempt to set Col to a value greater than the
+         --  maximum permissible line length.
+
+         if File.Line_Length /= 0 and then To > File.Line_Length then
+            raise Layout_Error;
+         end if;
+
+         --  If we are behind current position, then go to start of new line
+
+         if To < File.Col then
+            New_Line (File);
+         end if;
+
+         --  Loop to output blanks till we are at the required column
+
+         while File.Col < To loop
+            Put (File, ' ');
+         end loop;
+
+      --  Input case
+
+      else
+         --  If we are logically before a LM, but physically after it, the
+         --  file position still reflects the position before the LM, so eat
+         --  it now and adjust the file position appropriately.
+
+         if File.Before_LM then
+            File.Before_LM := False;
+            File.Before_LM_PM := False;
+            File.Line := File.Line + 1;
+            File.Col := 1;
+         end if;
+
+         --  Loop reading characters till we get one at the required Col value
+
+         loop
+            --  Read next character. The reason we have to read ahead is to
+            --  skip formatting characters, the effect of Set_Col is to set
+            --  us to a real character with the right Col value, and format
+            --  characters don't count.
+
+            ch := Getc (File);
+
+            --  Error if we hit an end of file
+
+            if ch = EOF then
+               raise End_Error;
+
+            --  If line mark, eat it and adjust file position
+
+            elsif ch = LM then
+               File.Line := File.Line + 1;
+               File.Col := 1;
+
+            --  If recognized page mark, eat it, and adjust file position
+
+            elsif ch = PM and then File.Is_Regular_File then
+               File.Page := File.Page + 1;
+               File.Line := 1;
+               File.Col := 1;
+
+            --  Otherwise this is the character we are looking for, so put it
+            --  back in the input stream (we have not adjusted the file
+            --  position yet, so everything is set right after this ungetc).
+
+            elsif To = File.Col then
+               Ungetc (ch, File);
+               return;
+
+            --  Keep skipping characters if we are not there yet, updating the
+            --  file position past the skipped character.
+
+            else
+               File.Col := File.Col + 1;
+            end if;
+         end loop;
+      end if;
+   end Set_Col;
+
+   procedure Set_Col (To : Positive_Count) is
+   begin
+      Set_Col (Current_Out, To);
+   end Set_Col;
+
+   ---------------
+   -- Set_Error --
+   ---------------
+
+   procedure Set_Error (File : File_Type) is
+   begin
+      FIO.Check_Write_Status (AP (File));
+      Current_Err := File;
+   end Set_Error;
+
+   ---------------
+   -- Set_Input --
+   ---------------
+
+   procedure Set_Input (File : File_Type) is
+   begin
+      FIO.Check_Read_Status (AP (File));
+      Current_In := File;
+   end Set_Input;
+
+   --------------
+   -- Set_Line --
+   --------------
+
+   procedure Set_Line
+     (File : File_Type;
+      To   : Positive_Count)
+   is
+   begin
+      --  Raise Constraint_Error if out of range value. The reason for this
+      --  explicit test is that we don't want junk values around, even if
+      --  checks are off in the caller.
+
+      if not To'Valid then
+         raise Constraint_Error;
+      end if;
+
+      FIO.Check_File_Open (AP (File));
+
+      if To = File.Line then
+         return;
+      end if;
+
+      if Mode (File) >= Out_File then
+         if File.Page_Length /= 0 and then To > File.Page_Length then
+            raise Layout_Error;
+         end if;
+
+         if To < File.Line then
+            New_Page (File);
+         end if;
+
+         while File.Line < To loop
+            New_Line (File);
+         end loop;
+
+      else
+         while To /= File.Line loop
+            Skip_Line (File);
+         end loop;
+      end if;
+   end Set_Line;
+
+   procedure Set_Line (To : Positive_Count) is
+   begin
+      Set_Line (Current_Out, To);
+   end Set_Line;
+
+   ---------------------
+   -- Set_Line_Length --
+   ---------------------
+
+   procedure Set_Line_Length (File : File_Type; To : Count) is
+   begin
+      --  Raise Constraint_Error if out of range value. The reason for this
+      --  explicit test is that we don't want junk values around, even if
+      --  checks are off in the caller.
+
+      if not To'Valid then
+         raise Constraint_Error;
+      end if;
+
+      FIO.Check_Write_Status (AP (File));
+      File.Line_Length := To;
+   end Set_Line_Length;
+
+   procedure Set_Line_Length (To : Count) is
+   begin
+      Set_Line_Length (Current_Out, To);
+   end Set_Line_Length;
+
+   ----------------
+   -- Set_Output --
+   ----------------
+
+   procedure Set_Output (File : File_Type) is
+   begin
+      FIO.Check_Write_Status (AP (File));
+      Current_Out := File;
+   end Set_Output;
+
+   ---------------------
+   -- Set_Page_Length --
+   ---------------------
+
+   procedure Set_Page_Length (File : File_Type; To : Count) is
+   begin
+      --  Raise Constraint_Error if out of range value. The reason for this
+      --  explicit test is that we don't want junk values around, even if
+      --  checks are off in the caller.
+
+      if not To'Valid then
+         raise Constraint_Error;
+      end if;
+
+      FIO.Check_Write_Status (AP (File));
+      File.Page_Length := To;
+   end Set_Page_Length;
+
+   procedure Set_Page_Length (To : Count) is
+   begin
+      Set_Page_Length (Current_Out, To);
+   end Set_Page_Length;
+
+   --------------
+   -- Set_WCEM --
+   --------------
+
+   procedure Set_WCEM (File : in out File_Type) is
+      Start : Natural;
+      Stop  : Natural;
+
+   begin
+      FIO.Form_Parameter (File.Form.all, "wcem", Start, Stop);
+
+      if Start = 0 then
+         File.WC_Method := Default_WCEM;
+
+      else
+         if Stop = Start then
+            for J in WC_Encoding_Letters'Range loop
+               if File.Form (Start) = WC_Encoding_Letters (J) then
+                  File.WC_Method := J;
+                  return;
+               end if;
+            end loop;
+         end if;
+
+         Close (File);
+         raise Use_Error with "invalid WCEM form parameter";
+      end if;
+   end Set_WCEM;
+
+   ---------------
+   -- Skip_Line --
+   ---------------
+
+   procedure Skip_Line
+     (File    : File_Type;
+      Spacing : Positive_Count := 1)
+   is
+      ch : int;
+
+   begin
+      --  Raise Constraint_Error if out of range value. The reason for this
+      --  explicit test is that we don't want junk values around, even if
+      --  checks are off in the caller.
+
+      if not Spacing'Valid then
+         raise Constraint_Error;
+      end if;
+
+      FIO.Check_Read_Status (AP (File));
+
+      for L in 1 .. Spacing loop
+         if File.Before_LM then
+            File.Before_LM := False;
+
+            --  Note that if File.Before_LM_PM is currently set, we also have
+            --  to reset it (because it makes sense for Before_LM_PM to be set
+            --  only when Before_LM is also set). This is done later on in this
+            --  subprogram, as soon as Before_LM_PM has been taken into account
+            --  for the purpose of page and line counts.
+
+         else
+            ch := Getc (File);
+
+            --  If at end of file now, then immediately raise End_Error. Note
+            --  that we can never be positioned between a line mark and a page
+            --  mark, so if we are at the end of file, we cannot logically be
+            --  before the implicit page mark that is at the end of the file.
+
+            --  For the same reason, we do not need an explicit check for a
+            --  page mark. If there is a FF in the middle of a line, the file
+            --  is not in canonical format and we do not care about the page
+            --  numbers for files other than ones in canonical format.
+
+            if ch = EOF then
+               raise End_Error;
+            end if;
+
+            --  If not at end of file, then loop till we get to an LM or EOF.
+            --  The latter case happens only in non-canonical files where the
+            --  last line is not terminated by LM, but we don't want to blow
+            --  up for such files, so we assume an implicit LM in this case.
+
+            loop
+               exit when ch = LM or else ch = EOF;
+               ch := Getc (File);
+            end loop;
+         end if;
+
+         --  We have got past a line mark, now, for a regular file only,
+         --  see if a page mark immediately follows this line mark and
+         --  if so, skip past the page mark as well. We do not do this
+         --  for non-regular files, since it would cause an undesirable
+         --  wait for an additional character.
+
+         File.Col := 1;
+         File.Line := File.Line + 1;
+
+         if File.Before_LM_PM then
+            File.Page := File.Page + 1;
+            File.Line := 1;
+            File.Before_LM_PM := False;
+
+         elsif File.Is_Regular_File then
+            ch := Getc (File);
+
+            --  Page mark can be explicit, or implied at the end of the file
+
+            if (ch = PM or else ch = EOF)
+              and then File.Is_Regular_File
+            then
+               File.Page := File.Page + 1;
+               File.Line := 1;
+            else
+               Ungetc (ch, File);
+            end if;
+         end if;
+      end loop;
+
+      File.Before_Upper_Half_Character := False;
+   end Skip_Line;
+
+   procedure Skip_Line (Spacing : Positive_Count := 1) is
+   begin
+      Skip_Line (Current_In, Spacing);
+   end Skip_Line;
+
+   ---------------
+   -- Skip_Page --
+   ---------------
+
+   procedure Skip_Page (File : File_Type) is
+      ch : int;
+
+   begin
+      FIO.Check_Read_Status (AP (File));
+
+      --  If at page mark already, just skip it
+
+      if File.Before_LM_PM then
+         File.Before_LM := False;
+         File.Before_LM_PM := False;
+         File.Page := File.Page + 1;
+         File.Line := 1;
+         File.Col  := 1;
+         return;
+      end if;
+
+      --  This is a bit tricky, if we are logically before an LM then
+      --  it is not an error if we are at an end of file now, since we
+      --  are not really at it.
+
+      if File.Before_LM then
+         File.Before_LM := False;
+         File.Before_LM_PM := False;
+         ch := Getc (File);
+
+      --  Otherwise we do raise End_Error if we are at the end of file now
+
+      else
+         ch := Getc (File);
+
+         if ch = EOF then
+            raise End_Error;
+         end if;
+      end if;
+
+      --  Now we can just rumble along to the next page mark, or to the
+      --  end of file, if that comes first. The latter case happens when
+      --  the page mark is implied at the end of file.
+
+      loop
+         exit when ch = EOF
+           or else (ch = PM and then File.Is_Regular_File);
+         ch := Getc (File);
+      end loop;
+
+      File.Page := File.Page + 1;
+      File.Line := 1;
+      File.Col  := 1;
+      File.Before_Upper_Half_Character := False;
+   end Skip_Page;
+
+   procedure Skip_Page is
+   begin
+      Skip_Page (Current_In);
+   end Skip_Page;
+
+   --------------------
+   -- Standard_Error --
+   --------------------
+
+   function Standard_Error return File_Type is
+   begin
+      return Standard_Err;
+   end Standard_Error;
+
+   function Standard_Error return File_Access is
+   begin
+      return Standard_Err'Access;
+   end Standard_Error;
+
+   --------------------
+   -- Standard_Input --
+   --------------------
+
+   function Standard_Input return File_Type is
+   begin
+      return Standard_In;
+   end Standard_Input;
+
+   function Standard_Input return File_Access is
+   begin
+      return Standard_In'Access;
+   end Standard_Input;
+
+   ---------------------
+   -- Standard_Output --
+   ---------------------
+
+   function Standard_Output return File_Type is
+   begin
+      return Standard_Out;
+   end Standard_Output;
+
+   function Standard_Output return File_Access is
+   begin
+      return Standard_Out'Access;
+   end Standard_Output;
+
+   --------------------
+   -- Terminate_Line --
+   --------------------
+
+   procedure Terminate_Line (File : File_Type) is
+   begin
+      FIO.Check_File_Open (AP (File));
+
+      --  For file other than In_File, test for needing to terminate last line
+
+      if Mode (File) /= In_File then
+
+         --  If not at start of line definition need new line
+
+         if File.Col /= 1 then
+            New_Line (File);
+
+         --  For files other than standard error and standard output, we
+         --  make sure that an empty file has a single line feed, so that
+         --  it is properly formatted. We avoid this for the standard files
+         --  because it is too much of a nuisance to have these odd line
+         --  feeds when nothing has been written to the file.
+
+         --  We also avoid this for files opened in append mode, in
+         --  accordance with (RM A.8.2(10))
+
+         elsif (File /= Standard_Err and then File /= Standard_Out)
+           and then (File.Line = 1 and then File.Page = 1)
+           and then Mode (File) = Out_File
+         then
+            New_Line (File);
+         end if;
+      end if;
+   end Terminate_Line;
+
+   ------------
+   -- Ungetc --
+   ------------
+
+   procedure Ungetc (ch : int; File : File_Type) is
+   begin
+      if ch /= EOF then
+         if ungetc (ch, File.Stream) = EOF then
+            raise Device_Error;
+         end if;
+      end if;
+   end Ungetc;
+
+   -----------
+   -- Write --
+   -----------
+
+   --  This is the primitive Stream Write routine, used when a Text_IO file
+   --  is treated directly as a stream using Text_IO.Streams.Stream.
+
+   procedure Write
+     (File : in out Text_AFCB;
+      Item : Stream_Element_Array)
+   is
+      pragma Warnings (Off, File);
+      --  Because in this implementation we don't need IN OUT, we only read
+
+      function Has_Translated_Characters return Boolean;
+      --  return True if Item array contains a character which will be
+      --  translated under the text file mode. There is only one such
+      --  character under DOS based systems which is character 10.
+
+      text_translation_required : Boolean;
+      for text_translation_required'Size use Character'Size;
+      pragma Import (C, text_translation_required,
+                     "__gnat_text_translation_required");
+
+      Siz : constant size_t := Item'Length;
+
+      -------------------------------
+      -- Has_Translated_Characters --
+      -------------------------------
+
+      function Has_Translated_Characters return Boolean is
+      begin
+         for K in Item'Range loop
+            if Item (K) = 10 then
+               return True;
+            end if;
+         end loop;
+         return False;
+      end Has_Translated_Characters;
+
+      Needs_Binary_Write : constant Boolean :=
+        text_translation_required and then Has_Translated_Characters;
+
+   --  Start of processing for Write
+
+   begin
+      if File.Mode = FCB.In_File then
+         raise Mode_Error;
+      end if;
+
+      --  Now we do the write. Since this is a text file, it is normally in
+      --  text mode, but stream data must be written in binary mode, so we
+      --  temporarily set binary mode for the write, resetting it after. This
+      --  is done only if needed (i.e. there is some characters in Item which
+      --  needs to be written using the binary mode).
+      --  These calls have no effect in a system (like Unix) where there is
+      --  no distinction between text and binary files.
+
+      --  Since the character translation is done at the time the buffer is
+      --  written (this is true under Windows) we first flush current buffer
+      --  with text mode if needed.
+
+      if Needs_Binary_Write then
+         if fflush (File.Stream) = -1 then
+            raise Device_Error;
+         end if;
+
+         set_binary_mode (fileno (File.Stream));
+      end if;
+
+      if fwrite (Item'Address, 1, Siz, File.Stream) /= Siz then
+         raise Device_Error;
+      end if;
+
+      --  At this point we need to flush the buffer using the binary mode then
+      --  we reset to text mode.
+
+      if Needs_Binary_Write then
+         if fflush (File.Stream) = -1 then
+            raise Device_Error;
+         end if;
+
+         set_text_mode (fileno (File.Stream));
+      end if;
+   end Write;
+
+begin
+   --  Initialize Standard Files
+
+   for J in WC_Encoding_Method loop
+      if WC_Encoding = WC_Encoding_Letters (J) then
+         Default_WCEM := J;
+      end if;
+   end loop;
+
+   Initialize_Standard_Files;
+
+   FIO.Chain_File (AP (Standard_In));
+   FIO.Chain_File (AP (Standard_Out));
+   FIO.Chain_File (AP (Standard_Err));
+
+end Ada.Text_IO;