Components
CICS services emulate the functions of the operating system, but provide services tailored to support only quasi-reentrant transaction processing that are more efficient than the generalized services in the operating system and much simpler for programmers to use, particularly with respect to communication with diverse terminal devices.
Each CICS region comprises one major task on which every transaction runs, although certain services such as access to DB2 data use other tasks (TCBs). Within a region transactions are cooperatively multitasked — they are expected to be well-behaved and yield the CPU rather than wait. CICS services handle this automatically.
Each unique CICS "Task" or transaction is allocated its own dynamic memory at start-up and subsequent requests for additional memory were handled by a call to the "Storage Control program" (part of the CICS nucleus or "kernel"), which is analogous to an operating system.
A CICS system consiste of the online nucleus, batch support programs, and applications services.
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Famous quotes containing the word components:
“Hence, a generative grammar must be a system of rules that can iterate to generate an indefinitely large number of structures. This system of rules can be analyzed into the three major components of a generative grammar: the syntactic, phonological, and semantic components.”
—Noam Chomsky (b. 1928)