IMPLEMENTATION MODULE SysIO;
(* Thin wrapper over the C shim's external procedures. *)

PROCEDURE m2write(VAR s : ARRAY OF CHAR);
  EXTERNAL;

PROCEDURE m2writeln;
  EXTERNAL;

PROCEDURE m2writeint(n : INTEGER);
  EXTERNAL;

PROCEDURE m2writechar(c : CHAR);
  EXTERNAL;

PROCEDURE m2readchar() : CHAR;
  EXTERNAL;

PROCEDURE m2readint() : INTEGER;
  EXTERNAL;

PROCEDURE Write(VAR s : ARRAY OF CHAR);
BEGIN
  m2write(s)
END Write;

PROCEDURE WriteLn;
BEGIN
  m2writeln
END WriteLn;

PROCEDURE WriteInt(n : INTEGER);
BEGIN
  m2writeint(n)
END WriteInt;

PROCEDURE WriteChar(c : CHAR);
BEGIN
  m2writechar(c)
END WriteChar;

PROCEDURE ReadChar() : CHAR;
BEGIN
  RETURN m2readchar()
END ReadChar;

PROCEDURE ReadInt() : INTEGER;
BEGIN
  RETURN m2readint()
END ReadInt;

END SysIO.