Adds a new Resource Manager (RM) participant to a transaction.

    $JOIN_RMW always waits for the request to complete before
    returning to the caller. Other than this, it is identical to
    $JOIN_RM.

    Format

      SYS$JOIN_RMW  [efn] ,[flags] ,iosb ,[astadr] ,[astprm] ,rm_id

                    [,[tid] ,[part_name] ,[rm_context] ,[timout]

                    ,[bid] ]

    C Prototype

      int sys$join_rmw  (unsigned int efn, unsigned int

                        flags, struct _iosb *iosb, void

                        (*astadr)(__unknown_params), int

                        astprm, unsigned int rm_id,...);