Callback function when there is a data packet for a task

# GearmanClient::setDataCallback

(PECL gearman >= 0.6.0)

GearmanClient::setDataCallback — Callback function when there is a data packet for a task

### 説明

public GearmanClient::setDataCallback ( callable `$callback` ) : bool

Sets the callback function for accepting data packets for a task. The callback function should take a single argument, a GearmanTask object.

### パラメータ

`callback`

  A function or method to call

### 返り値

成功した場合に `TRUE` を、失敗した場合に `FALSE` を返します。

### 参考

- GearmanClient::setCompleteCallback() - Set a function to be called on task completion
- GearmanClient::setCreatedCallback() - Set a callback for when a task is queued
- GearmanClient::setExceptionCallback() - Set a callback for worker exceptions
- GearmanClient::setFailCallback() - Set callback for job failure
- GearmanClient::setStatusCallback() - Set a callback for collecting task status
- GearmanClient::setWarningCallback() - Set a callback for worker warnings
- GearmanClient::setWorkloadCallback() - Set a callback for accepting incremental data updates