(PECL gearman >= 0.5.0)
GearmanClient::setCompleteCallback — Set a function to be called on task completion
Use to set a function to be called when a GearmanTask is completed, or when GearmanJob::sendComplete() is invoked by a worker (whichever happens first).
This callback executes only when executing a GearmanTask using GearmanClient::runTasks(). It is not used for individual jobs.
callback
A function to be called
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