Extracts the second part of input (ss in dd-MMM-yyyy
       hh:mm:ss.cc).

1  –  Input

       A date.

2  –  Output

       An unsigned integer from 0 to 59.

3  –  Example

       DTR> DECLARE CAL USAGE DATE EDIT_STRING X(23).
       DTR> CAL = "NOW"; PRINT CAL

                 CAL

        1-Feb-1990 08:51:11.55

       DTR> PRINT FN$SECOND (CAL)

         FN$SECOND

                 11

       DTR>