If the application invokes handler.nack() or allows handler to go out of scope, then the service will redeliver the message.
With exactly-once delivery subscriptions, the service will stop redelivering the message once the application invokes handler.ack() and the invocation succeeds. With best-efforts subscriptions, the service may redeliver the message, even after a successful handler.ack() invocation.
If handler is not an rvalue, you may need to use std::move(handler).ack() or std::move(handler).nack().
[[["Easy to understand","easyToUnderstand","thumb-up"],["Solved my problem","solvedMyProblem","thumb-up"],["Other","otherUp","thumb-up"]],[["Hard to understand","hardToUnderstand","thumb-down"],["Incorrect information or sample code","incorrectInformationOrSampleCode","thumb-down"],["Missing the information/samples I need","missingTheInformationSamplesINeed","thumb-down"],["Other","otherDown","thumb-down"]],["Last updated 2025-03-21 UTC."],[[["The webpage provides a list of different versions of `PullResponse` for Google Cloud Pub/Sub, spanning from version 2.11.0 up to the latest release candidate 2.37.0-rc."],["The content describes the behavior of message redelivery based on whether the application uses `handler.ack()` or `handler.nack()`, or allows the `handler` to go out of scope."],["With exactly-once delivery subscriptions, message redelivery stops after a successful `handler.ack()` invocation, but with best-effort subscriptions, redelivery may still occur even after a successful `handler.ack()`."],["The page references `structgoogle_1_1cloud_1_1pubsub_1_1PullResponse` which is a response for blocking pull."],["The page provides a link for documentation on exactly-once-delivery."]]],[]]
