(* Output.def redirect output.

Copyright (C) 2021-2023 Free Software Foundation, Inc.
Contributed by Gaius Mulley <gaius.mulley@southwales.ac.uk>.

This file is part of GNU Modula-2.

GNU Modula-2 is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3, or (at your option)
any later version.

GNU Modula-2 is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
General Public License for more details.

You should have received a copy of the GNU General Public License
along with GNU Modula-2; see the file COPYING3.  If not see
<http://www.gnu.org/licenses/>.  *)

DEFINITION MODULE Output ;

(*
    Title      : Output
    Author     : Gaius Mulley
    System     : GNU Modula-2
    Date       : Fri Jul  9 12:17:35 2021
    Revision   : $Version$
    Description: provides an interface to output redirection for common
                 output procedures.
*)

FROM NameKey IMPORT Name ;
FROM DynamicStrings IMPORT String ;


(*
   Open - attempt to open filename as the output file.
          TRUE is returned if success, FALSE otherwise.
*)

PROCEDURE Open (filename: ARRAY OF CHAR) : BOOLEAN ;


(*
   Close - close the output file.
*)

PROCEDURE Close ;


(*
   Write - write a single character to the output file.
*)

PROCEDURE Write (ch: CHAR) ;


(*
   WriteString - write an unformatted string to the output.
*)

PROCEDURE WriteString (s: ARRAY OF CHAR) ;


(*
   KillWriteS - write a string to the output and free the string afterwards.
*)

PROCEDURE KillWriteS (s: String) ;


(*
   WriteS - write a string to the output.  The string is not freed.
*)

PROCEDURE WriteS (s: String) ;


(*
   WriteKey - write a key to the output.
*)

PROCEDURE WriteKey (key: Name) ;


(*
   WriteLn - write a newline to the output.
*)

PROCEDURE WriteLn ;


(*
   WriteCard - write a cardinal using fieldlength characters.
*)

PROCEDURE WriteCard (card, fieldlength: CARDINAL) ;


(*
   StartBuffer - create a buffer into which any output is redirected.
*)

PROCEDURE StartBuffer ;


(*
   EndBuffer - end the redirection and return the contents of the buffer.
*)

PROCEDURE EndBuffer () : String ;


END Output.