# event_buffer_set_callback

(PECL libevent >= 0.0.4)

event_buffer_set_callback — Set or reset callbacks for a buffered event

### 说明

event_buffer_set_callback ( resource `$event` , mixed `$readcb` , mixed `$writecb` , mixed `$errorcb` [, mixed `$arg` ] ) : bool

Sets or changes existing callbacks for the buffered `event`.

### 参数

`event`

  Valid buffered event resource.

`readcb`

  Callback to invoke where there is data to read, or NULL if no callback is desired.

`writecb`

  Callback to invoke where the descriptor is ready for writing, or NULL if no callback is desired.

`errorcb`

  Callback to invoke where there is an error on the descriptor, cannot be NULL.

`arg`

  An argument that will be passed to each of the callbacks (optional).

### 返回值

成功时返回 `TRUE`， 或者在失败时返回 `FALSE`。