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complicated / too many steps","tooComplicatedTooManySteps","thumb-down"],["Out of date","outOfDate","thumb-down"],["Samples / code issue","samplesCodeIssue","thumb-down"],["Other","otherDown","thumb-down"]],["Last updated 2025-08-14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 comprehensive list of Google Cloud Pub/Sub C++ library versions, ranging from the latest release candidate (2.37.0-rc) down to version 2.11.0.\u003c/p\u003e\n"],["\u003cp\u003eEach version listed links to the \u003ccode\u003ePullResponse\u003c/code\u003e struct documentation, offering detailed information for that specific library release, in the \u003ccode\u003egoogle::cloud::pubsub\u003c/code\u003e namespace.\u003c/p\u003e\n"],["\u003cp\u003eThe content describes the behavior of message redelivery within the \u003ccode\u003ePullResponse\u003c/code\u003e context, stating that messages will be redelivered if \u003ccode\u003ehandler.nack()\u003c/code\u003e is invoked or if the handler goes out of scope.\u003c/p\u003e\n"],["\u003cp\u003eExactly-once delivery subscriptions will cease message redelivery upon a successful \u003ccode\u003ehandler.ack()\u003c/code\u003e, while best-effort subscriptions may still redeliver messages even after a successful acknowledgement.\u003c/p\u003e\n"],["\u003cp\u003eUsers are advised to use \u003ccode\u003estd::move(handler).ack()\u003c/code\u003e or \u003ccode\u003estd::move(handler).nack()\u003c/code\u003e if the handler is not an rvalue, allowing for proper resource management.\u003c/p\u003e\n"]]],[],null,[]]
