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If the checkout is not possible (for example, the remainder of available licenses have been checked out in the meantime), this information will be relayed to the application, which will behave in the manner specified. If, for example, five heartbeats in a row fail, automatic heartbeats will call an exit() function on behalf of the application and print error information to the screen. This behavior can be overridden with the HEARTBEAT_EXIT_FUNCTION callback, described in Heartbeats.
Using a counter to prevent license overuse
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