DEFINITION MODULE Traps;

  IMPORT EM;

  CONST
	ERRTOOLARGE =	64;	(* stack size of process too large *)
	ERRTOOMANY =	65;	(* too many nested traps + handlers *)
	ERRNORESULT =	66;	(* no RETURN from function procedure *)
	ERRCARDOVFL =	67;	(* CARDINAL overflow *)

  TYPE	TrapHandler = EM.TrapHandler;

  PROCEDURE InstallTrapHandler(t: TrapHandler): TrapHandler;
  (* Install a new trap handler, and return the previous one.
     Parameter of trap handler is the trap number.
  *)

  PROCEDURE Message(str: ARRAY OF CHAR);
  (* Write message "str" on standard error, preceeded by filename and
     linenumber if possible
  *)

  PROCEDURE Trap(n: INTEGER);
  (* cause trap number "n" to occur *)

END Traps.