eio_fallocate

(PECL eio >= 0.0.1dev)

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

說明

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

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.

注意: File should be opened for writing

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

參數(shù)

fd

Stream, Socket resource, or numeric 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

請求的優(yōu)先級：EIO_PRI_DEFAULT，EIO_PRI_MIN，EIO_PRI_MAX 或 null。如果是 null，pri 將設(shè)為 EIO_PRI_DEFAULT。

callback

callback 函數(shù)在請求完成時被調(diào)用。其應(yīng)匹配一下原型：

void callback(mixed $data, int $result[, resource $req]);
data

傳遞給請求的用戶數(shù)據(jù)。

result

針對請求的結(jié)果的值。通常是相應(yīng)的系統(tǒng)調(diào)用返回的值。

req

可選的請求資源，可被 eio_get_last_error() 之類的函數(shù)使用。

data

Arbitrary variable passed to callback.

返回值

eio_fallocate() returns request resource on success, 或者在失敗時返回 false.