# dio_write

(PHP 4 >= 4.2.0, PHP 5 < 5.1.0)

dio_write — Writes data to fd with optional truncation at length

### 说明

dio_write ( resource `$fd` , string `$data` [, int `$len` = 0 ] ) : int

dio_write() writes up to `len` bytes from `data` to file `fd`.

### 参数

`fd`

  The file descriptor returned by dio_open().

`data`

  The written data.

`len`

  The length of data to write in bytes. If not specified, the function writes all the data to the specified file.

### 返回值

Returns the number of bytes written to `fd`.

### 参见

- dio_read() - Reads bytes from a file descriptor