It’s the 1980s, and legacy systems are already a problem. IBM is still shipping source code for big-iron internals, says this mainframe pilot fish.
“IBM discontinued supporting BTAM under CICS, but we had a major customer who communicated via CICS BTAM,” fish says.
Translation: The big customer uses the CICS transaction-processing system, and connects to it over telecommunication lines using the very old BTAM protocol — and IBM has just stopped supporting that approach.
Boss instructs fish to put BTAM support back in — after all, she does have access to the source code. Fish thinks that’s a bad plan, since changing internal mainframe system code is never a good idea.
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