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 latest version available is 2.37.0-rc, which can be accessed via a direct link."],["The provided content lists multiple versions of `PullResponse` for Google Cloud Pub/Sub, spanning from version 2.11.0 to 2.37.0-rc."],["The `PullResponse` is used to process the result for a blocking pull."],["Messages may be redelivered if the `handler.nack()` is called or the scope of the `handler` ends."],["For subscriptions with exactly-once delivery, messages will not be redelivered after successful `handler.ack()`, but best-efforts subscriptions could redeliver messages in such cases."]]],[]]
