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Class Drivers

All methods defined by a class should be accessible through one entry point, called Class Driver. The calling sequence of the class driver is as follows:

CALL driver (msg,ivdsn,instr,idone)

msg

Character variable, NULL terminated, containing the message

ivdsn

Object handle

instr

A structure of extra information - see below

idone

Integer flag returned by the driver - 0 means 'not-done', anything else means done

instr is a structure which allows the caller and the driver to pass extra information. Driver Call Structure

structure/instr_t/
        character*16 name    ! Object name
        integer class        ! Object class
        integer type         ! Object type (sub-class)
        integer lun          ! Fortran unit number for possible output
        integer pnt          ! Pointer for returned data
      end structure

This form of the input structure allows the caller to request extra information to be returned via pnt.

• Messages to the driver
• Examples