eio_fallocate

(PECL eio >= 0.0.1dev)

eio_fallocate — Allows the caller to directly manipulate the allocated disk space for a file

说明

resource eio_fallocate ( int $fd , int $mode , int $offset , int $length [, int $pri = EIO_PRI_DEFAULT [, callable $callback = NULL [, mixed $data = NULL ]]] )

eio_fallocate() allows the caller to directly manipulate the allocated disk space for the file specified by fd file descriptor for the byte range starting at offset and continuing for length bytes.

Note: File should be opened for writing

EIO_O_CREAT should be logically OR'd with EIO_O_WRONLY, or EIO_O_RDWR

参数

fd

The file descriptor, e.g. returned by eio_open().

mode

Currently only one flag is supported for mode: EIO_FALLOC_FL_KEEP_SIZE (the same as POSIX constant FALLOC_FL_KEEP_SIZE).

offset

Specifies start of the byte range.

length

Specifies length the byte range.

pri

请求的优先级: EIO_PRI_DEFAULT, EIO_PRI_MIN, EIO_PRI_MAX, or NULL. 如果是 NULL , pri 将设为 EIO_PRI_DEFAULT.

callback

callback 函数将在请求结束时被调用. 必须符合此原型:


void callback($data, $result);

$data 是传给该请求的特定数据. $result 包含特定请求的结果值, 通常是相应的系统调用的返回值.

data

Arbitrary variable passed to callback.

返回值

eio_fallocate() returns request resource on success or FALSE on error.