MODULE echo; IMPORT STextIO; (*DEE 2016-09-23*)
  FROM TextIO IMPORT ReadToken;
  FROM ProgramArgs IMPORT IsArgPresent, NextArg, ArgChan;

  TYPE string = ARRAY [1..256] OF CHAR;
  
  PROCEDURE echo; (*Echo command arguments to standard output.*)
    VAR argstr: string;
  BEGIN IF IsArgPresent() THEN NextArg() END; (* Eat command name. *)
    WHILE IsArgPresent() DO
      ReadToken(ArgChan(), argstr);
      STextIO.WriteString(argstr);
      NextArg();
      IF IsArgPresent() THEN STextIO.WriteChar(' ') END
    END;
    STextIO.WriteLn
  END echo;

BEGIN echo
END echo.