(PECL gearman <= 0.5.0)
GearmanClient::setClientCallback — Callback function when there is a data packet for a task (deprecated)
Sets the callback function for accepting data packets for a task. The callback function should take a single argument, a GearmanTask object.
注意:
This method has been replaced by GearmanClient::setDataCallback() in the 0.6.0 release of the Gearman extension.
A function or method to call
成功した場合に TRUE を、失敗した場合に FALSE を返します。