Werk #5460: Waiting without a wait condition immediately returns now
Component | Livestatus | ||||||||||||||||
Title | Waiting without a wait condition immediately returns now | ||||||||||||||||
Date | Nov 17, 2017 | ||||||||||||||||
Level | Trivial Change | ||||||||||||||||
Class | Bug Fix | ||||||||||||||||
Compatibility | Incompatible - Manual interaction might be required | ||||||||||||||||
Checkmk versions & editions |
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Note: This change only affects users writing their own tools for the Livestatus interface, and only those tools which rely on an edge case.
Up to now, Livestatus had a special obscure case: Using a WaitTrigger header in a query without a WaitCondition header resulted in waiting for the trigger exactly once. This is a misfeature, because it is effectively useless and doesn't do what one might expect: Due to spurious wakeups (https://en.wikipedia.org/wiki/Spurious_wakeup), waiting might return earlier basically at any time.
To fix this behaviour, the special case has been removed, and a missing WaitCondition always has its expected semantics (always true) now. Note that this is consistent with a missing Filter header, which means "no filtering".