Overview of BBXS
service routines that are dynamically loaded into extended CSA
extended CSA memory used for
control table (BBCT)
subsystem service routines
shared data areas
Some of this storage is page-fixed.
From an external view, BBXS is a proper subsystem. However, unlike subsystems such as JES2 and JES3, BBXS does not require its own address space. BBXS uses only the SSCTSUSE field of the subsystem's CVT or SSCVT to anchor the BMC Subsystem Services Control Table (BBCT). The BBCT is built during BBXS initialization, and primarily contains pointers to BBXS service routines. These routines return data in response to specific requests from BMC products.