The CONV$CONVERT routine uses the Convert utility to
    perform the actual conversion begun with CONV$PASS_FILES and
    CONV$PASS_OPTIONS. Optionally, the routine can return statistics
    about the conversion.

    Note that the CONV$CONVERT routine may return appropriate File
    Definition Language (FDL) error messages to the calling program,
    where applicable.

    Format

      CONV$CONVERT  [status_block_address] [,flags]

                    [,callback_routine]