0-2-2-understand-atomic-exchange

name	0.2.2-understand-atomic_exchange
description	[0.2.2] Atomic operation that reads the current value of a variable and writes a new value in a single indivisible ste

understand-atomic_exchange

CALL NUMBER: ?.atomic_exchange DEFINITION: Atomic operation that reads the current value of a variable and writes a new value in a single indivisible step, returning the old value.

Invoke this skill to understand atomic_exchange down to its primitives. The RELATIVE ROOT below is the least-fixed-point closure of everything it bundles from — the full import cone, grouped by the lib each prim comes from. Projected from a prover-typed KB (MAP/SWI-Prolog consistency gate): every reference below resolves.

THE RELATIVE ROOT (the import cone, by lib)

CONSUMERS (what needs this)

mcs_lock, mcs_lock_wait_for_successor

---

Projected from the concurrency synchronization primitives and memory models KB (155 concepts / 137 relations) — consistency-typed by MAP; the facet list after the colon IS the cross-lib dependency web.

(leaf — this is an actual skill.)