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User-defined states are used to extend the Application Host system states for application specific purposes. These custom states are passed into the caller as a parameter to the polling callback function.
User-defined , application states MUST have values from the set of whole numbers, {x ε Z | x ≥ 0} be integers >= 0.
WARNING: Negative numbers are RESERVED for the system states and CANNOT be used for user-defined, application states.
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