PACKET callee DEFINES callee:

TASK PROC callee (TASK CONST t): 
  IF im wait THEN trick 1 (t); trick 2 ELSE niltask FI.
im wait: (status(t) AND 3) = 2. 
END PROC callee; 
 
PROC trick 1 (TASK CONST t): 
  INT VAR x := pcb(t,11), y:=pcb(t,12); 
END PROC trick1; 
 
TASK PROC trick 2: TASK VAR calle; calle END PROC trick2; 
 
END PACKET callee;