  No SHOW CONTROL? (CTRL/Y, CTRL/T status?) 
 The Question is:
 
How can you determine if your, or any other, process has control_y or control_t
 set?
 
 The Answer is:
 
  Please see the DCL lexical F$ENVIRONMENT (keyword CONTROL), or please
  see RTL calls such as LIB$DISABLE_CTRL and LIB$ENABLE_CTRL.
 
