DEFINITION MODULE InOut ;

IMPORT ASCII ;
FROM DynamicStrings IMPORT String ;
EXPORT QUALIFIED EOL, Done, termCH, OpenInput, OpenOutput,
                 CloseInput, CloseOutput,
                 Read, ReadString, ReadInt, ReadCard,
                 Write, WriteLn, WriteString, WriteInt, WriteCard,
                 WriteOct, WriteHex,
                 ReadS, WriteS ;

CONST
   EOL = ASCII.EOL ;

VAR
   Done  : BOOLEAN ;
   termCH: CHAR ;


(*
   OpenInput - reads a string from stdin as the filename for reading.
               If the filename ends with `.' then it appends the defext
               extension. The global variable Done is set if all
               was successful.
*)

PROCEDURE OpenInput (defext: ARRAY OF CHAR) ;


(*
   CloseInput - closes an opened input file and returns input back to
                StdIn.
*)

PROCEDURE CloseInput ;


(*
   OpenOutput - reads a string from stdin as the filename for writing.
                If the filename ends with `.' then it appends the defext
                extension. The global variable Done is set if all
                was successful.
*)

PROCEDURE OpenOutput (defext: ARRAY OF CHAR) ;


(*
   CloseOutput - closes an opened output file and returns output back to
                 StdOut.
*)

PROCEDURE CloseOutput ;


(*
   Read - reads a single character from the current input file.
          Done is set to FALSE if end of file is reached or an
          error occurs.
*)

PROCEDURE Read (VAR ch: CHAR) ;


(*
   ReadString - reads a sequence of characters. Leading white space
                is ignored and the string is terminated with a character
                <= ' '
*)

PROCEDURE ReadString (VAR s: ARRAY OF CHAR) ;


(*
   WriteString - writes a string to the output file.
*)

PROCEDURE WriteString (s: ARRAY OF CHAR) ;


(*
   Write - writes out a single character, ch, to the current output file.
*)

PROCEDURE Write (ch: CHAR) ;


(*
   WriteLn - writes a newline to the output file.
*)

PROCEDURE WriteLn ;


(*
   ReadInt - reads a string and converts it into an INTEGER, x.
             Done is set if an INTEGER is read.
*)

PROCEDURE ReadInt (VAR x: INTEGER) ;


(*
   ReadInt - reads a string and converts it into an INTEGER, x.
             Done is set if an INTEGER is read.
*)

PROCEDURE ReadCard (VAR x: CARDINAL) ;


(*
   WriteCard - writes the CARDINAL, x, to the output file. It ensures
               that the number occupies, n, characters. Leading spaces
               are added if required.
*)

PROCEDURE WriteCard (x, n: CARDINAL) ;


(*
   WriteInt - writes the INTEGER, x, to the output file. It ensures
              that the number occupies, n, characters. Leading spaces
              are added if required.
*)

PROCEDURE WriteInt (x: INTEGER; n: CARDINAL) ;


(*
   WriteOct - writes the CARDINAL, x, to the output file in octal.
              It ensures that the number occupies, n, characters.
              Leading spaces are added if required.
*)

PROCEDURE WriteOct (x, n: CARDINAL) ;


(*
   WriteHex - writes the CARDINAL, x, to the output file in hexadecimal.
              It ensures that the number occupies, n, characters.
              Leading spaces are added if required.
*)

PROCEDURE WriteHex (x, n: CARDINAL) ;


(*
   ReadS - returns a string which has is a sequence of characters.
           Leading white space is ignored and string is terminated
           with a character <= ' '.
*)

PROCEDURE ReadS () : String ;


(*
   WriteS - writes a String to the output device.
            It returns the string, s.
*)

PROCEDURE WriteS (s: String) : String ;


END InOut.