Fault Tolerance Callback Actions
Fault tolerance callback functions receive an action argument—one of three tokens, which instruct the callback function to behave in one of three ways:
| • | ACTIVATE
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This action token instructs the callback function to switch the member process into active mode.
| • | DEACTIVATE
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This action token instructs the callback function to switch the member process into inactive mode.
| • | PREPARE_TO_ACTIVATE
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This action token is a hint that Rendezvous fault tolerance software might soon issue an instruction to activate. It instructs the callback function to prepare for possible activation by doing any time-consuming steps that can be done before the actual order to activate.
Remember that the prepare-to-activate hint is exactly that—a hint. Several circumstances might later render activation unnecessary.
The names of the tokens vary slightly among the different programming languages.
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C |
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C++ |
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Java |
Tokens are defined as constant fields of |
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.NET |
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