deep-roots learning program · module 08

Module 08 — COBOL & the mainframe world

5 chapters · ~15k words · the memory model with no heap

Every chapter: first principles, What insiders know, a See it yourself lab, connections, and a quiz with worked answers.

z/Architecture, addressing modes, storage keys, PSW — the metal under COBOL.

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WORKING-STORAGE, LOCAL-STORAGE, LINKAGE — allocation with exact semantics.

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PICTURE as a byte-level type system: COMP, COMP-3, REDEFINES, OCCURS.

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GETMAIN/FREEMAIN, storage protection, quasi-reentrancy, above/below the line.

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The economics, the migration trap, what 60 years of fixed records taught everyone.

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the exam

fin

Every chapter, worked answers behind the fold.

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