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 |
Checkmk Edition | Checkmk Raw (CRE) |
Checkmk Version | 1.4.0p25 1.5.0i1 |
Level | Trivial Change |
Class | Bug Fix |
Compatibility | Incompatible - Manual interaction might be required |
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".