PHP マニュアル: Send fail status (deprecated)

public bool GearmanJob::fail()

Sends failure status for this job, indicating that the job failed in a known way (as opposed to failing due to a thrown exception).

注意:
This method has been replaced by GearmanJob::sendFail in the 0.6.0 release of the Gearman extension.

この関数にはパラメータはありません。

成功した場合に true を、失敗した場合に false を返します。