Windows System Programming Third Edition

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CHAPTER 8 THREAD SYNCHRONIZATION

sections, held for a long period of time, defeat concurrency and can impact

performance.

• Associate the mutex directly with the resource it is designed to protect,

possibly in a data structure. (Programs 8–1 and 8–2 use this technique.)

• Document the invariant as precisely as possible, in words or even

as a logical,

or Boolean, expression. The invariant is a property of the protected resource

that you guarantee holds outside the critical code section. An invariant might

be of the form: “the element is i n both or neither list,” “the checksum on the

data buffer is valid,” “the linked l

ist is valid,” or “

.” A prec ...