Unlocks pages that were previously locked in the working set by
    the Lock Pages in Working Set ($LKWSET) service.

    Format

      SYS$ULWSET  inadr ,[retadr] ,[acmode]

    C Prototype

      int sys$ulwset  (struct _va_range *inadr, struct _va_range

                      *retadr, unsigned int acmode);