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"]],[["Missing the information I need","missingTheInformationINeed","thumb-down"],["Too complicated / too many steps","tooComplicatedTooManySteps","thumb-down"],["Out of date","outOfDate","thumb-down"],["Samples / code issue","samplesCodeIssue","thumb-down"],["Other","otherDown","thumb-down"]],["Last updated 2025-08-14 UTC."],[[["\u003cp\u003eThe webpage provides a list of different versions for \u003ccode\u003egoogle::cloud::pubsub::PullResponse\u003c/code\u003e, ranging from version 2.11.0 up to the latest release candidate, 2.37.0-rc.\u003c/p\u003e\n"],["\u003cp\u003eThe content describes the behavior of message redelivery, stating that messages will be redelivered if \u003ccode\u003ehandler.nack()\u003c/code\u003e is invoked or the handler goes out of scope.\u003c/p\u003e\n"],["\u003cp\u003eFor exactly-once delivery subscriptions, messages stop being redelivered after a successful \u003ccode\u003ehandler.ack()\u003c/code\u003e invocation, while best-effort subscriptions may still redeliver messages even after acknowledgment.\u003c/p\u003e\n"],["\u003cp\u003eThe page details that if handler is not an rvalue, std::move(handler).ack() or std::move(handler).nack() may need to be used.\u003c/p\u003e\n"],["\u003cp\u003eA link is provided to the pubsub documentation for more information on exactly-once-delivery.\u003c/p\u003e\n"]]],[],null,[]]
