RECIO_OPE

 NUMBER:  40

 ERROR CODE:  F

 MESSAGE TEXT:  recursive I/O operation

 EXPLANATION:  While processing an I/O statement for a logical unit,
 another I/O operation on the same logical unit was attempted.  One
 of the following conditions may have occurred:

  o  A function subprogram that performs I/O to the same logical
     unit was referenced in an expression in an I/O list or variable
     format expression.

  o  An I/O statement was executed at AST level for the same logical
     unit.

  o  An exception handler (or a procedure it called) executed an I/O
     statement in response to a signal from an I/O statement for the
     same logical unit.